carbon footprint essay titles

National Geographic content straight to your inbox—sign up for our popular newsletters here

Our guide to the UK & Ireland

• Terms of Use
• Privacy Policy
• Your US State Privacy Rights
• Children's Online Privacy Policy
• Interest-Based Ads
• About Nielsen Measurement
• Do Not Sell or Share My Personal Information
• Nat Geo Home
• Attend a Live Event
• Book a Trip
• Inspire Your Kids
• Shop Nat Geo
• Visit the D.C. Museum
• Learn About Our Impact
• Support Our Mission
• Advertise With Us
• Customer Service
• Renew Subscription
• Manage Your Subscription
• Work at Nat Geo
• Sign Up for Our Newsletters
• Contribute to Protect the Planet

Copyright © 1996-2015 National Geographic Society Copyright © 2015-2024 National Geographic Partners, LLC. All rights reserved

• ENVIRONMENT

What is a carbon footprint—and how to measure yours

Determining a carbon footprint is easier said than done, and it’s not clear how much weight we should put on it.

As awareness of climate change   grows, so does the desire to do something about it . But the scale of the problems it causes—from wildfires to melting glaciers to droughts—can seem utterly overwhelming . It can be hard to make a connection between our everyday lives and the survival of polar bears, let alone how we as individuals can help turn the situation around.

One way to gain a quantifiable understanding of the impacts of our actions, for good and bad, is through what is known as a carbon footprint. But while the concept is gaining traction—Googling “How do I reduce my carbon footprint?” yields almost 27 million responses—it is not always fully understood .

What is a carbon footprint?

So, what exactly is a carbon footprint? According to Mike Berners-Lee , a professor at Lancaster University in the UK and author of The Carbon Footprint of Everything , it is “the sum total of all the greenhouse gas emissions that had to take place in order for a product to be produced or for an activity to take place.”

For most consumers in developed countries, these products and activities tend to fall into four principal categories: household energy use, transport, food, and everything else, which is mostly the products we buy, from utensils to clothes to cars to television sets.

Each of these activities and products has its own footprint; a person’s carbon footprint is the combined total of the products they buy and use, the activities they undertake, and so on. A person who regularly consumes beef will have a   larger food footprint than his vegan neighbor, but that neighbor’s overall footprint may be larger if she drives an hour to work and back in an SUV each day while our meat-eater bicycles to his office nearby. Both their footprints may pale in comparison to the businesswoman across the street, who flies first-class cross-country twice a month.

Unsurprisingly, in general terms the size of a person’s carbon footprint tends to increase with wealth. In his book, Berners-Lee writes that the average global citizen has a carbon footprint that is equivalent to the emission of seven tons of carbon dioxide per year. However, that figure is approximately 13 tons for the average Briton and roughly 21 tons per person in the United States.; The “average American takes just a couple of days to match the annual footprint of the average Nigerian or Malian,” he writes.

How is a carbon footprint calculated?

It isn’t easy to calculate a carbon footprint; indeed, Berners-Lee calls it the “essential but impossible” measurement.

FREE BONUS ISSUE

Consider, for example, the personal carbon cost of taking a commercial flight. On the one hand, the calculation is straightforward: take how much fuel a plane burns and how many greenhouse gases are emitted during the course of a flight and divide by the number of passengers. But the footprint is larger for first-and-business-class passengers, because they take up more space and because their higher cost creates an extra incentive for the flight to actually take place. Other considerations include how much cargo the plane is carrying, and the altitude at which the plane flies .

Even so, it is a relatively simple calculation compared to assessing the emissions involved in every step of, say, the manufacture of a car: the emissions that take place at the assembly plant, the generation of electricity to power that plant, the transport of all the component items, the factories at which the components were made, the creation of the machinery used at those factories and at the assembly plant and so on, all the way back to the extraction of the minerals that are the car’s building blocks.

Because of the complexity involved in such calculations, Berners-Lee concedes that in such cases it is “never possible to be completely accurate.” The good news, he argues, is that for most individuals, that doesn’t matter. “Usually, it’s good enough just to have a broad idea,” he says.

What steps a person can take to reduce their personal footprint the most of course depends on the kind of lifestyle they presently live, and the same actions are not equally effective for everyone. For example, switching to an electric car is far more impactful in Vermont , where more than half the state’s electricity is generated by hydropower, than in West Virginia, where it is almost entirely generated by coal. Berners-Lee notes that, “for some people, flying may be 10 percent of their footprint, for some people it’s zero, and for some it’s such a huge number that it should be the only thing they should be thinking about.”

You May Also Like

Forget your carbon footprint—your climate shadow is what really matters

What is El Niño—and will it lead to more snow this winter?

Cobalt powers our lives. What is it—and why is it so controversial?

A cornucopia of calculators.

To that end, in recent years, a veritable cornucopia of personal carbon footprint calculators has emerged online. By entering information about your household energy use, food consumption, and travel habits, for example, these calculators aim to provide you with an approximation of the amount of greenhouse gases being emitted to support your way of life. This one from the Nature Conservancy focuses on home energy use, transportation, diet, and shopping; this, from the United States Environmental Protection Agency , also considers transportation and energy use but adds in waste—specifically, how much you recycle. It also enables you to calculate how much your footprint could be reduced by taking steps such as insulating your home, driving less, or procuring a more fuel-efficient vehicle. This one shows just how much of an idealized personal carbon budget is taken up by consuming two large cheeseburgers a month or spending two nights in a hotel.

Are carbon footprints just fossil fuel propaganda?

It has been claimed that the earliest such calculator appeared in 2004 as part of the “ Beyond Petroleum” campaign of oil giant BP —a fact that causes some observers to criticize the pressure to reduce personal carbon footprints as a “sham” to “promote the slant that climate change is not the fault of an oil giant, but that of individuals.”

“A few years ago, Shell promoted a tweet into my thread that asked, ‘What are you doing to reduce your carbon footprint?’” recalls Katharine Hayhoe , chief scientist for The Nature Conservancy and a professor at Texas Tech University. “So, I replied with something along the lines of, ‘You are responsible for 2 percent of global emissions, equivalent to the entire country of Canada; when you have a plan to get rid of those, I’d be happy to talk to you about my personal carbon footprint.’ And they hid my reply.”

“It’s really important that all of us think about what we’re consuming, whether it’s fish or furniture or air conditioning: where it came from, what impact it had,” says Kert Davies, director of the Climate Investigations Center . “But industry then turned it around and made it: ‘It’s not our fault, you’re using our product. You deal with it.’”

That is all the more egregious, he argues, given that the fossil fuel industry has directly fought to limit some of the measures that are often cited as ways for people to reduce their personal carbon footprints: more fuel-efficient vehicle standards, or clean energy technology , for example.

“If not for fossil fuel companies, you would already be driving an EV, your house would be more efficient to run if industry hadn’t blocked solutions and obscured the truth about the urgency of addressing climate change ,” Davies adds.

Do carbon footprint calculators have a role?

Hayhoe argues that there are other problems with the concept of personal carbon footprints, not least the fact that many of the proposed means to reduce those footprints are unavailable to those who, for example, don’t have access to public transport, or can’t afford the upfront cost of an electric car or a heat pump, or who live in food deserts , where healthier, lower-impact foods such as vegetables and grains are harder to come by.

“There’s a role for the personal carbon footprint concept in high income countries among middle-to-high income people,” she explains. “There’s a very big role for the personal carbon footprint among the very richest people in the world . But we have to realize it is a limited concept—it does not apply to everyone.”

In addition, she argues, acting by ourselves is just one small part of what is required to affect change in a system that, despite the best individual efforts, remains dominated by the production and use of fossil fuels.

“I would say personal carbon footprint calculators are a useful tool to assess the impact of your immediate actions: where you live, where you travel, what you eat,” she says. “But what’s much more important than your personal carbon footprint is your climate shadow . Where do you keep your money? How do you vote? What about the businesses you work with, or the university you’re a part of, or the Rotary Club of which you’re a member—what are they doing, and how could you advocate for change?

“So, in a nutshell, when people ask me what they should do, I say: Do something, anything, but then talk about it. The only way to bring the carbon footprint of everybody in rich countries to where it needs to be for a sustainable planet is to change the system, and to change the system we have to use our voice.”

Related Topics

• CARBON FOOTPRINT
• CLIMATE CHANGE

How wildfire smoke infiltrates your home—and how to get rid of it

How to compost—and why it’s good for the environment

Wildfire season is getting longer—and more intense. Here's how to prepare.

5 simple things you can do to live more sustainably

Biden wants to cut U.S. climate pollution in half—here’s how

• Environment
• Paid Content

History & Culture

• History & Culture
• History Magazine
• Mind, Body, Wonder
• Terms of Use
• Privacy Policy
• Your US State Privacy Rights
• Children's Online Privacy Policy
• Interest-Based Ads
• About Nielsen Measurement
• Do Not Sell or Share My Personal Information
• Nat Geo Home
• Attend a Live Event
• Book a Trip
• Inspire Your Kids
• Shop Nat Geo
• Visit the D.C. Museum
• Learn About Our Impact
• Support Our Mission
• Advertise With Us
• Customer Service
• Renew Subscription
• Manage Your Subscription
• Work at Nat Geo
• Sign Up for Our Newsletters
• Contribute to Protect the Planet

Copyright © 1996-2015 National Geographic Society Copyright © 2015-2024 National Geographic Partners, LLC. All rights reserved

What's Your Carbon Footprint?

How much carbon dioxide do you send into the atmosphere? Anytime you do something that requires fossil fuels — like riding in a car, flying in a plane, buying something, eating something, or even just watching TV — you emit carbon dioxide into the atmosphere.

Our individual carbon dioxide emissions are a part of the total emissions on Earth. All of the cars and trucks that we drive, the boxes we ship, the products we manufacture, the emissions from the food we eat, the air-conditioning we use in our buildings — it all adds up.

Some people emit much more carbon dioxide than others. Worldwide, the average person produces about four tons of carbon dioxide each year. In the United States, each person produces about 16 tons of carbon dioxide each year. Because carbon dioxide is a greenhouse gas , adding more of it to the atmosphere causes our climate to warm .

Driving a car that burns gasoline releases much more carbon dioxide than carpooling or taking public transportation, so driving makes your carbon footprint larger than other transportation choices. Ride a bike or walk instead to shrink your carbon footprint even more.

Pixabay/prvideotv

Calculate Your Carbon Footprint

You can figure out how much your actions affect greenhouse gases by using a carbon footprint calculator. A carbon footprint is the total amount of carbon dioxide released into the atmosphere as a result of human activities. Your carbon footprint is the total carbon dioxide released due to your individual activities. Your household’s carbon footprint is the total carbon dioxide released by your home and all the people who live there. A carbon footprint calculator typically takes into account the greenhouse gases you produce at home and while traveling. It can also include the greenhouse gases produced to transport and make the food you eat and the things you buy.

Check out the carbon footprint calculators listed below and use one to calculate your carbon footprint:

• CoolClimate Calculator : This in-depth calculator adds up your carbon emissions from home, travel, food, and shopping. It allows you to compare your footprint to others and helps you identify the changes you can make to reduce your impact on climate change.
• Zerofootprint Youth Carbon Calculator : This kid-friendly calculator guides you through the process of calculating your family’s carbon footprint. You don’t need a login or email address, but you must name your school and birthday to use the tool.
• EPA Household Carbon Footprint Calculator : Gather your home energy bills before you start for the most accurate calculation of your home’s carbon emissions. This calculator includes home energy, cars, and recycling, but doesn’t include other types of emissions. It includes helpful information about how much carbon dioxide you can save by making small changes around your house to decrease your impact on climate change.

Shrinking Your Footprint

Once you have calculated your carbon footprint, think about how you could make it smaller. We add greenhouse gases to the atmosphere as we go about our daily lives, but often we can make choices that reduce these emissions. For example, you might choose to ride a bike to the store rather than driving a car. Or you might find that renewable energy is available from your power company and make a switch. By reducing your carbon dioxide emissions, you will shrink your carbon footprint, and your choices will help keep the climate livable. The choices we make every day in our homes, our travel, the food we eat, and what we buy and throw away can help ensure a stable climate for future generations.

Catrin Jakobsson, with data from  Wynes and Nicolas (2017)

• Climate Solutions
• How Do We Reduce Greenhouse Gases?
• Future Climate: Explore the Possibilities
• Energy Choices and Climate Change

An official website of the United States government

The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

• Publications
• Account settings

Preview improvements coming to the PMC website in October 2024. Learn More or Try it out now .

• Advanced Search
• Journal List
• Springer Nature - PMC COVID-19 Collection

Carbon footprint in Higher Education Institutions: a literature review and prospects for future research

Karen valls-val.

Department of Mechanical Engineering and Construction, Universitat Jaume I, Av. Sos Baynat s/n, 12071 Castellón, Spain

María D. Bovea

Higher Education Institutions (HEI) or universities, as organisations engaged in education, research and community services, play an important role in promoting sustainable development. Therefore, they are increasingly linked to the initiative of calculating their carbon footprint (CF), which is a tool to assess sustainability from the perspective of greenhouse gas (GHG) emissions. The aim of this study is to carry out a systematic review of the current situation of CF assessment in academic institutions by analysing different key elements, such as the time period, methodologies and practises, calculation tools, emission sources, emission factors and reduction plans. The review protocol considered articles published until March 2021. Of the articles reviewed, 35 are aimed specifically at calculating the CF of HEI, while the remaining articles consist of review, activity-specific CF assessment or GHG emission reduction articles. Clear differences have been identified when results are compared for the normalised CF (average of 2.67 t CO 2 e/student, ranging from 0.06 to 10.94) or the percentage of carbon offsetting, only considered in 14% of the studies and ranging from 0.09 to 18%. The main reason for this is the lack of standardisation as regards the time metric (year, semester), functional unit (student, employee, area) and data collection boundary (scope 1, 2, 3), the emissions sources and emission factors, mainly for scope 3 (water consumption and treatment, waste treatment, office, ICT and laboratory consumables, commuting and travel, construction materials, canteens, etc.), and the inclusion or not of the effect of carbon offset projects to offset the CF (aim of the project and absorption sources and factors). However, despite the differences, a reduction over time is clearly observed. Therefore, CF in HEI requires further improvements and solutions to a number of challenges, including the definition of representative emission sources, the creation of a robust emission factor database and the development of tools/methodologies that cover all the needs of this type of organisation.

Graphic abstract

Introduction

Academic institutions play a crucial and significant role in helping society to meet the climate and environmental challenges proposed by international frameworks, such as Green Deal (COM 640 2019 ) and the framework for achieving climate neutrality (COM 80 2020 ) focussed on achieving climate neutrality in the short/medium term. Higher Education Institutions (HEI), as organisations committed to education and research, play a significant role in preparing responsible graduates involved in maintaining sustainable development, and they themselves have to be an example for their students and staff as well as for society as a whole. For this reason, calculating, tracking and reporting their own carbon footprint (CF) is a starting point from which to become sustainable organisations.

The term “carbon footprint” is defined by the IPCC Guidelines ( 2006 ) as “a representation of the effect on climate in terms of the total amount of greenhouse gases (GHG) that are produced, measured in units of CO 2 e as a result of the activities of an organization”. GHG emissions can be calculated for each source using the following formula:

where the GHG emissions from a specific source (E S ) are obtained from the product between the activity data from that specific source (AD S ), which represents a quantitative measure of the source expressed in units (for example litres of petrol or kWh of electricity), and its respective GHG emission factor (EF S ), which is a coefficient that allows activity data to be converted into GHG emission. Once the total GHG emissions from all sources have been calculated, they are added up to quantify the total CF in units of carbon dioxide equivalent (CO 2 e). This is a common unit for describing GHG emissions, for any quantity and type of GHG it signifies the amount of CO 2, which would have the equivalent global warming impact.

Although organisations contribute significantly to GHG emissions, methodological guidance for them is less developed and less prescriptive than for products (Robinson et al.  2015 ). There are different international standards for calculating the CF of organisations. Amongst others, the most notable regulatory frameworks are the GHG Protocol ( 2004 ), ISO 14064–1 ( 2006 ) and ISO/TR 14069 ( 2013 ), PAS 2050 ( 2011 ) and PAS 2060 (2014). Although initially they were applied to verify the requirements for quantifying GHG emissions within organisations under the Kyoto Protocol ( 2008 ), their use is currently becoming widespread in other types of organisations that are voluntarily interested in calculating and communicating their CF.

Higher Education Institutions, also known as universities, are establishments devoted to post-secondary education and research that award academic degrees in different disciplines. Therefore, as organisations engaged in education, research and community services, they play an important role in sustainable development and the fight against climate change (Cordero et al. 2020 ). CF is a very useful tool for exercising a greater degree of control over activities that impact on the environment (Robinson et al. 2018 ) and also provides a baseline on which to evaluate the effect of future mitigation efforts on-campus (Letete et al. 2011 ).

Moreover, the role of HEI in sustainability is already recognised by different international declarations, such as the Talloires Declaration (TD 1990 ) or the Cre-Copernicus University Charta (Copernicus 1993 ), associations/networks, such as the CRUE’s Sectoral Sustainability Commission (CRUE 2002 ), the Association for the Advancement of Sustainability in Higher Education (AASHE 2005 ), the American College and University Presidents’ Climate Commitment (ACUPCC 2007 ), which was rebranded as the Carbon Commitment (CC 2015 ), the International Sustainable Campus Network (ISCN 2007 ) or the Global Universities Partnership on Environment for Sustainability (GUPES 2012 ), as well as rankings, such as the Times Higher Education-World University Ranking (THE 2004 ), the Sustainability Monitoring, Assessment and Rating System (STARS 2013 ) or the UI GreenMetric World University Ranking on Sustainability (GreenMetric 2010 ).

For these reasons, universities, as an example of sustainable organisations, should take a leading role in the fight against climate change and thus in the calculation, monitoring, reporting, reduction or even offsetting of their CF. However, as a preliminary step for calculating the CF of HEI, it is necessary to understand their activities that contribute to climate change by creating a greenhouse gas emissions inventory (Bailey and LaPoint 2016 ). HEI typically consists of a mixture of buildings used for classrooms, laboratories, offices, canteens, residences, etc. Some of them have their own power plants, transport circuits, water systems or health services, mainly depending on the number of students they host. Any of these activities have emission sources contributing to the CF, which need to be identified and quantified. This task can become complicated depending on the type and size of the institution. In this study, the use of university buildings and the material needed to carry out academic activities are considered. Santovito and Abiko ( 2018 ) offered recommendations on how to prepare the GHG inventory, identified some relevant emission sources and allowed a better visualisation of the opportunities for GHG mitigation. Yet, there is no specific standardised methodology for conducting the inventory and calculating the GHG emissions generated for the case of educational institutions.

Several reviews can be found in the literature. Some of them are focussed on analysing methodological aspects of the CF calculation, Fenner et al. ( 2018 ) for the building sector or Durojaye et al. ( 2020 ) in general, highlighting both the lack of standardisation in spite of the different frameworks developed for that purpose. Others are specific reviews dedicated to specific sectors, such as construction/buildings (Onat and Kucukvar ( 2020 ) for the construction industry, Che Muhammad Fatihi Hafifi Wahid et al. ( 2019 ) for highway developments and Schwartz et al. ( 2018 ) for refurbished and new buildings), population (Purwanto et al. ( 2019 ) for settlement activities and Heinonen et al. ( 2020 ) for consumptions in settlement, region, city or country), food and drink (Navarro et al. ( 2017 ) for wine and wineries, Brade and Brade ( 2014 ) for milk and milk products production, Rugani et al. ( 2013 ) for wine, Nijdam et al. ( 2012 ) for animal food and their substitutes and Pirlo ( 2012 ) for milk production), healthcare (Rizan et al. ( 2020 ) for surgical operations and Alshqaqeeq et al. ( 2020 ) for hospital services), metal (Nilsson et al. ( 2017 ) for Cu and Zn production from primary and secondary sources), tourism (Sun et al. ( 2020 ) for transport, accommodation, catering, shopping, entertainment, telecommunications, etc.), water (Cornejo et al. ( 2014 ) for water reuse and desalination) and Information and Communication Technology (ICT) (Grimm et al. ( 2014 ) for workplace hardware, server, networks and IT-services). However, no specific reviews have been done for educational activities, as Fig.  1 shows. So, this study fills this gap, encompassing research activity in CF in this field, from the date of publication of the first CF framework (2004), to the present (March 2021).

Other reviews in the literature classified by sector and years covered ( n  = number of articles)

Although there are no general reviews related to this subject, the literature contains a few studies focussed on comparing the CFs of different HEIs belonging to specific associations in a specific geographical area. So that, Sinha et al. ( 2010 ) compared the CF from institutions that were signatories of the American College and University Presidents’ Climate Commitment (ACUPCC) and Bailey and LaPoint ( 2016 ) compared the CF from nine universities located in Texas (USA). Both studies applied the Clean Air Cool Planet Calculator (CA-CP 2020 ) to compile and model the emission data from the institutions compared in each study. However, when trying to compare the CF from different studies, the scope, boundaries, emission sources, emission factors, etc. are specifically defined for each case study, making it difficult to carry out comparisons amongst different HEIs. This fact highlights the lack of a common framework.

Taking into account this context, the aim of this study is to carry out a review of studies calculating the CF of HEI worldwide in order to identify the most common practises related to the methodological aspects of the calculation and to compare results. This will make it possible to establish a common framework that facilitates comparability of the studies. The paper is structured as follows: Sect.  2 presents a four-stage methodology used to select the studies under review and as the basis for comparing those studies in general terms, as well as their methodology and results; Sect.  3 presents the results obtained after applying the methodology; Sect.  4 discusses the results; and, lastly, Sect.  5 draws some final conclusions.

Research methodology

This systematic review follows a structure designed to achieve consistency, robustness and transparency in research. The methodology guides the selection of case studies focussed on calculating the CF in HEI and the evaluation rules to identify the information to be extracted. The research methodology has four stages, as shown in Fig.  2 and described below:

• Stage 1 aims to identify the literature focussed on quantifying the CF of HEI and whose content included fully detailed and defined case studies with a consistent methodology and results.
• Stage 2 includes the general mapping of the literature selected in stage 1, considering temporal aspects and the main descriptive characteristics of the institution under analysis (location, size, etc.).
• Stage 3 goes deeper into the analysis of specific aspects related to the calculation of CF, that is, methodologies applied, goal definition, scopes, source emissions, etc.
• Stage 4 focuses on the comparison amongst the CF of the HEI analysed and the identification of the causes underlying the differences found.

Methodology

Stage 1: identification of articles

The Scopus database was used as the main search engine for selecting the literature, using “carbon footprint, university”, “greenhouse, university”, “carbon footprint, higher education” and “greenhouse, higher education” as strings in the article title and keywords. To avoid limitations due to the capacity of the database search, other sources, such as GoogleScholar and ScienceDirect were used with these same strings to complete the list of articles to be analysed. In addition, the list obtained was completed with specific articles found in the list of references of those articles focussed on literature reviews. By applying this procedure, 84 articles were found. A first screening of the source title and article title/keywords resulted in the rejection of those that did not correspond to indexed research articles or conference papers, and those that did not focus on the calculation of the carbon footprint of HEI, respectively. In addition, duplicates were also rejected, thus reducing the sample to 55 articles. A second screening of the content of the abstracts was conducted and articles that were not aimed at calculating the carbon footprint of one or more HEI were excluded, thereby further reducing the sample to 44 articles. After a third screening of the full text, only articles that included fully detailed and defined case studies with a consistent methodology and results were included. A final sample of 35 articles was selected, as reported in Table ​ Table1. 1 . A descriptive content analysis was carried out, considering the aspects detailed in Fig.  2 .

Universities’ carbon footprint

a Country: AU (Australia), CL (Chile), CO (Colombia), EC (Ecuador), ES (Spain), ID (Indonesia), IN (India), KR (South Korea), MY (Malaysia), MX (Mexico), NG (Nigeria), NO (Norway), NZ (New Zeland), PK (Pakistan), SA (Saudi Arabia), TH (Thailand), UK (United Kingdom), US (United States), ZA (South Africa)

b University type: N (National), PRIV (Private), P (Public)

c If multiple years are reported, data corresponds to the most recent year

d Boundary: I (Institution as a whole), C (Campus), B (Building, School)

e CF: Includes emissions of different greenhouse gases, in terms of Global Warming Potential (CO 2 e), obtained by applying the emission factors corresponding to the standard applied

f Aim of the study: S (static carbon footprint), E (evolution over time), C (comparison against other Institutions)

g Results: D (disaggregated by buildings), S (source contribution)

h Standard: BSI (British Standards Institution), GHGP (GHG Protocol Standard), IPCC (Intergovernmental Panel on Climate Change), N/A (Not Available)

i Tool: CA-CP (Clean Air Cool Planet Carbon Calculator); EIO-LCA (software developed by the Green Design Institute at Carnegie Mellon University); IELab (Australian Industrial Ecology Virtual Laboratory); U-NXT (Umberto NXT)

*Calculated from data included in the article

Other studies were not included in this review although they did calculate the CF, because this calculation was linked to specific university activities. For example, Chung et al. ( 2014 ) and Sippel et al. ( 2018 ) calculated the CF due to some students’ campus activities in Tajen University (Taiwan) and in the University of Applied Science in Konstanz (Germany), respectively, while Kulsuwan et al. ( 2019 ) only took into account the students' electricity consumption in Mahidol University Amnat Charoen Campus (Thailand). Barros et al. ( 2018 ), Pérez-Neira et al. ( 2020 ) and Rao et al. ( 2017 ) calculated the CF of transportation habits in the Federal University of Technology (Brazil), the University of León (Spain) and the Symbiosis International University (India), respectively, while Beardsley and Morton ( 2009 ) did the same for university sponsored air travels. In addition, Schwarz and Bonhotal ( 2018 ) determined the CF of a compost facility at Cornell University (USA), Stephan et al. ( 2020 ) examined the embodied CF in materials on the Parkville campus of the University of Melbourne (Australia) and Song et al. ( 2016 ) calculated that of scientific publications at Dalian University of Technology (China). On the other hand, Filimonau et al. ( 2021 ) compared the carbon intensity of on-campus and off-campus higher education, taking advantage of the unique opportunity of the COVID-19 pandemic.

Stage 2: general mapping

As a starting point of the review, a general mapping of the 35 research papers reported in Table ​ Table1 1 was carried out by analysing the following general aspects related to the time period analysed and the main characteristics of the institution:

Temporal evolution of the literature related to calculation of CF of higher educational institutions, by country

• Type of institution 86% of the studies correspond to public higher education institutions, 11% to private ones and the remaining 3% to national ones. Therefore, a greater involvement of public higher education institutions is observed.
• Year analysed 34% of the studies were conducted between 2000 and 2010, while the remaining 66% were carried out in the decade 2011–2020. As Fig.  3 shows, there is a significant increase in the number of articles published over the years, mainly in 2020. This may be due to the fact that HEI is more aware of environmental issues and also their commitment to contribute to their decarbonisation as a sustainability strategy.
• Time period analysed Some studies calculated the carbon footprint for one academic year (29%), while others did so for a fiscal year (68%) and only one of them considered a single semester (Kandananond 2017 ). The results are lower when only one semester is calculated, so this study is not comparable with the rest.
• Boundary 43% of the studies analyse the whole institution (I, in Table ​ Table1), 1 ), 48% analyse only one campus of the institution (C, in Table ​ Table1), 1 ), while the remaining 9% analyse only one building/school (B, in Table ​ Table1). 1 ). It is thus observed that universities prefer to carry out the analysis of a single campus, as the different campuses often act independently.
• Size of the institution As Table ​ Table1 1 reports, two main parameters are considered for measuring the size of the institution: people and area. The parameter people is considered in 86% of the studies, although it is measured according to three different variables: students in 77% of the studies, employees in 57% of the studies and per capita (as the sum of students and employees) in 66% of the studies. The parameter area is considered in 43% of the studies. This aspect is important as it allows a comparison of CF to be carried out amongst different institutions.

Stage 3: methodological aspects

A content analysis of the selected articles was performed to identify the main methodological aspect followed in each one. This was a feedback process defining the criteria used to classify each article in order to support the results and discussion of findings. The methodological elements evaluated for each article selected are reported in Table ​ Table1 1 and analysed below:

• Standard applied for the CF calculation As described in the introduction section, there are different international standards for calculating the CF. Only 17% of the studies reviewed fail to indicate the standard used as a basis. Of the rest, 54% use GHG Protocol ( 2004 ), 20% use (IPCC Guidelines 2006 ), 11% use ISO 14,064–1 (2006), and PAS 2050 ( 2011 ) is used by Budihardjo et al. ( 2020 ) and Thurston and Eckelman ( 2011 ).
• Aim of the study Although the main aim of all the studies is to evaluate the CF of the institution/campus or building/school, three different secondary objectives were also identified. Some studies analyse the evolution of emissions over time (40%) while the rest only calculate emissions during a specific year (60%). In addition, 46% of the studies compare their emissions with the CF of other universities and 80% of the studies analysed the effect of different measures aimed at reducing the CF.

Table ​ Table2 2 reports the specific measures applied in the literature to reduce the CF of higher education institutions, classified by the scope they have an influence over. In addition to the measures reported in Table ​ Table2, 2 , there are other strategies that affect specific aspects of the institutions. At the buildings level, strategies, such as designs for low-energy buildings are proposed by Baboulet and Lenzen ( 2010 ) and Ozawa-Meida et al. ( 2013 ), infrastructure interventions are carried out using techniques and materials with a low carbon footprint by Varón-hoyos et al. ( 2021 ) or minimising the construction of new buildings by Jung et al. ( 2016 ) and Riedy and Daly ( 2010 ). Moreover, establishing a structured sustainability office/group responsible for monitoring, tracking and advocating for sustainability initiatives is proposed by Riedy and Daly ( 2010 ) and Bailey and LaPoint ( 2016 ), and integrating an environmental management system, is proposed by Rodríguez-Andara et al. ( 2020 ), since it will facilitate the calculation of emissions and their mitigation. In specific HEI, which use animals for teaching or research purposes, Butt ( 2012 ) proposed decreasing the number of grazing animals and increasing the per animal productivity or decreasing the amount of dung and urine added to the pasture through restricted grazing.

Specific actions to reduce the CF

23 % of the studies analysed the improvement that would be obtained by applying these actions by accurately calculating the tCO 2 e saved or obtaining the specific percentage of reduction in emissions, while the rest of the studies reviewed only comment on the recommendations (see “Action CF improvement analysis (%)” row in Table ​ Table2 2 ).

Emission sources considered in the literature

a Scope 1: S (stationary consumption), R (leakage of refrigerants), V (vehicle fleet)

b Scope 2: P (purchased), G (generated)

c Consumption: W (water), P (paper), F (food), LC (laboratory chemicals), EE (electronic equipment), FE (Fertiliser)

d Transport: BT (business travel), C (commuting), S (supplies)

e WT: Wastewater

f Cons: Construction

g Elec: Electricity (transportation and distribution losses from purchased electricity)

*Article with recommendations for preparing the GHG inventory for university campuses

Apart from the emission sources reported in Table ​ Table3, 3 , which are commonly considered in the general literature focussed on the calculation of CF, other specific emission sources are considered in the studies reviewed, such as procurement of glassware, plasticware and capital woods (e.g. equipment and setups for scientific laboratories) (Sangwan et al. 2018 ), farm machinery (Ologun and Wara 2014 ) and trips for parents/friends visiting the campus (Ozawa-Meida et al. 2013 ).

Moreover, not all the source emissions are always considered in the same scope. Leakage of refrigerants is usually considered in Scope 1, although Sangwan et al. ( 2018 ) included them in Scope 3. On the contrary, other emission sources which are usually considered in Scope 3 are included in Scope 1 in some studies. For example, the purchase of fertilisers is included in Scope 1 by Bailey and LaPoint ( 2016 ) and Clabeaux et al. ( 2020 ), water supply by Budihardjo et al. ( 2020 ), Syafrudin et al. ( 2020 ) and Ullah et al. ( 2020 ) and wastewater treatment by Clabeaux et al. ( 2020 ) and Criollo et al. ( 2019 ). Finally, fuel used in power generators, which is usually considered in Scope 1, is included in Scope 2 by Güereca et al. ( 2013 ).

Figure  4 shows a graphic representation of the percentage distribution of the emission sources considered in the studies reviewed. As can be seen, not all emission sources have the same level of consideration. It can be observed that 100% of the studies consider scope 2, 86% consider scope 1 and 94% consider some source from scope 3. In scope 1, 72% consider stationary consumption, 83% consider the vehicle fleet, while only 33% consider the leakage of refrigerants. In scope 2, all the studies consider emissions from purchasing electricity and only Gu et al. ( 2019 ) considered the generation of electricity (renewable energy). Regarding scope 3, the five sources of emission that are considered the most are commuting (75%), generation of waste (75%), business trips (56%) and the consumption/procurement of paper (47%) and water (36%).

Emission sources considered in the articles analyse

Regarding the emission factors applied for each source of emissions, it can be observed that they are quite variable and depend mainly on the country, in which the institution under study is located. Current emission factors are available from many handbooks, government publications and the literature searches of appropriate research papers and journals. Some studies do not report the reference source of the emission factors (7 %) and none of them report the specific list of emission factors that are applied. Some studies used emission factors provided by official government sources, for example, Butt ( 2012 ) from New Zealand, Criollo et al. ( 2019 ) from UK, Mendoza-Flores et al. ( 2019 ) from Mexico, Ridhosari and Rahman ( 2020 ) from Indonesia or Rodríguez-Andara et al. ( 2020 ) from Spain. Most of them are based on relevant sources, such as IPCC, DEFRA or EPA.

• Data source Data related to the consumption of energy, fuel, water, etc. are usually obtained directly from primary sources (field data obtained directly from the institution under analysis) in the studies reviewed, that is, through bills, counters, etc. and for the same base year, which allows reliable and accurate results to be obtained. For commuting and paper consumption, however, data are commonly obtained through a survey carried out with students and/or employers, which involves a certain degree of uncertainty since it depends on the veracity of the answers and the respondents’ level of involvement. Nevertheless, due to limited data availability, some studies need to make assumptions, such as Letete et al. ( 2011 ) that considers the consumption of LPG, acetylene and transport in November 2007 as the average consumption from January to October and the same electricity consumption for the previous year; other studies extrapolate daily or monthly data to annual data (Quintero-Núñez et al. ( 2015 ) calculates an average daily electricity consumption for winter and summer and extrapolates it to the total number of working days; Almufadi and Irfan ( 2016 ) extrapolate daily transport data to annual data and Iskandar et al. (2020b) calculate monthly carbon footprint), Güereca et al. ( 2013 ) extrapolates data from one building to the rest of the institution analysed and Ozawa-Meida et al. ( 2013 ) extrapolates commuting information extracted from surveys to the whole university. Other studies also used surveys to estimate data for the consumption of fuel in generators (Ologun and Wara, 2014 ), for electricity consumption by lighting/equipment (Güereca et al., 2013 ) and for LPG consumed in residential colony (Ullah et al. 2020 ).
• Tool for CF calculation Most of the studies reviewed (83%) do not use any commercial/free CF calculation tools; instead, the calculations are performed with their own means. The remaining studies applied different tools: Clean Air Cool Planet Carbon Calculator (CA-CP 2020 ) was used by Bailey and LaPoint ( 2016 ), Klein-Banai et al. ( 2010 ) and Moerschbaecher and Day ( 2010 ), Economic Input–Output Life Cycle Assessment on-line tool (EIO-LCA 2020 ) was employed by Thurston and Eckelman ( 2011 ), IELab ( 2020 ) was implemented by Stephan et al. ( 2020 ), Umberto Software (Umberto 2020 ) was the tool used by Sangwan et al. ( 2018 ) and SimaPro (Pre Consultants 2019 ) was employed by (Ullah et al. 2020 ).

Comparison of results

The annual CF is reported in all the studies reviewed, although they are not comparable due to the different sizes of the institutions/campuses/schools/faculties analysed. In order to create a meaningful study despite these differences and to obtain a good basis for comparing the CF, a normalisation based on different criteria (student, employee, capita and area) is applied, as reported in Table ​ Table4. 4 . In addition, comparing this rate with the location of the HEI also reveals differences: 5.25/2.30/2.25/1.77/0.67 t CO 2 e/student on average for North America, Africa, Europe, Asia and South America, respectively. As a general result, it can be observed that the range of variation is very wide, regardless of the standardisation criteria applied. Moreover, other studies, especially those focussed on assessing the CF of university purchases (t CO 2 e/€ purchased), obtain less representative results due to the variety of potential purchases: 0.38 kgCO 2 e/€ (Larsen et al. 2013 ), 0.34 kgCO 2 e/€ (Ozawa-Meida et al. 2013 ) or 2.81 kgCO 2 e/€ (Alvarez et al. 2014 ). This fact clearly denotes a lack of homogeneous criteria when conducting the study.

• Disaggregation of results All the studies calculate the CF for the defined boundary. However, 29% of the studies disaggregate the results per building of the institution/campus/school and 88% disaggregate them by the source causing the GHG emissions.
• Offset emissions Only 14% of the studies have calculated their compensation potential, obtaining an emission offset ranging from 0.09% to 18%. However, many studies (26%) recognise the importance of incorporating university reforestation. For this reason, they include offset emissions as one of their recommendations for reducing the Carbon Footprint (see “Offset emissions” row in Table ​ Table3 3 ).

Normalised CF according to different units

Clear differences have been identified when the normalised CF from different HEI are compared. The main reason for this is the lack of a single international standardisation method for calculating the CF for organisations and specifically for educational institutions, which present certain peculiarities when compared to organisations in other areas. This study has highlighted the main aspects that require international consensus in order to obtain comparable results.

The first aspect is related to the need to establish a common time metric and functional unit. As activities in HEI do not remain constant over time—including face-to-face teaching, exams, holidays, etc. (Bailey and LaPoint 2016 )—it is desirable not to extrapolate data from a specific period. It seems to be more advisable to consider the fiscal year (instead of the academic year) as a temporal basis for calculating the CF in educational institutions, since emission factors are revised and published annually. Hence, it is recommendable to implement mechanisms for keeping historical records.

Furthermore, consensus is needed as regards the reference unit applied to normalise the CF, in order to be able to make comparisons amongst HEI. It would be recommendable to use kg CO 2 e/student, since it is directly related to the function of the HEI. It is also in agreement with the definition of the functional unit in the LCA methodology (ISO 14040 2006 ).

To analyse the values of the CF in greater depth, the evolution of the CF/student over time is represented in Fig.  5 . It can be seen that, in spite of the differences amongst the studies reviewed, a trend is sensed towards the reduction in the CF over time, probably due to the increasing environmental awareness of HEI.

Normalised carbon footprint: temporal evolution of CF per student

As set out in the previous section, one of the main reasons for the differences observed amongst the normalised CF in the studies reviewed is the scope and the emission sources considered in each of them. Figure  6 shows the normalised CF for those studies that allow its calculation (78% of the studies reviewed). The bar that represents the value of the CF/student for each study is shown in colour, which depends on the contribution of each scope to the CF: green for scope 1, blue for scope 2 and yellow/red/purple for scope 3.

Emission sources

It should also be noted that the CF from each study are not directly comparable, since they do not include the same emission sources, as Figs.  4 and ​ and6 6 show. Some of them only consider a single emission source, while other studies use almost all those reported in Table ​ Table3. 3 . However, the contribution of each emission source is quite variable depending on the value of its corresponding emission factor. Figure  7 represents the average contribution that each source emission has on the CF of studies reviewed.

Contribution of emission sources

As can be seen in Fig.  7 , the major contribution to the CF in HEI comes from electricity consumption in buildings (scope 2), followed by daily commuting to and from the campus (scope 3), as also remarked by Bailey and LaPoint ( 2016 ) for universities located in U.S., Butt ( 2012 ) in New Zealand, Güereca et al. ( 2013 ) in México and Jung et al. ( 2016 ) in Korea. Scope 3 emissions represent the main source of CF in most of the HEI where they were counted. Scope 3 accounted for around 79% of the total CF of Montfort University (Ozawa-Meida et al. 2013 ), around 68% for the Curicó Campus of Talca University (Vásquez et al. 2015 ) and up to 80% in Castilla-La Mancha University (Gómez et al. 2016 ).

This discussion stresses the need for a standardised framework for calculating the CF of organisations and specifically for HEI. In addition, it is also important to remark the need to include scope 3 in the near future (it is usually optional), since it represents a large percentage of emissions and is a good source of action to reduce emissions.

Footprint assessment increases the level of environmental awareness of the population and provides a baseline to measure the impact of future policies and technical measures to reduce consumption and its associated GHG emissions. The results of HEI carbon footprinting will increase environmental awareness in the student population, which could then spill over to the larger population. With this goal in mind, the number of HEI that calculate their CF is gradually increasing and this sector has been able to reduce its environmental impact while increasing its efficiency.

This study conducted a global literature review focussed on carbon footprint analyses in the HEI sector and also pinpointed the main gaps in the literature. Although several standards have been developed in response to the need for transparency in reporting GHG emissions, there is no internationally accepted method for measuring, reporting and verifying offsets of GHG emissions from HEIs in a consistent and comparable way. Consequently, carbon footprint studies often yield widely divergent results and comparison of the CF of HEI is difficult. Indeed, even after normalising differences in the student population, the metric tons CO2-e per student varied between the HEI that were compared. This may be due to the time period considered, taking different methodologies or tools into account, the fact that each of them have incorporated different GHG emission sources in their scopes or have used different methods to obtain activity data, and even due to the use of specific/generic emission factors for each source. In addition, the application of action plans and offsetting projects to compensate the CF can also contribute to the differences in the CF from one university to another.

Hence, this study illustrates the importance of developing comprehensive and consistent GHG inventories for HEI, listing the GHG emission sources included and the factor emissions considered so that HEI is not compared unfairly.

Moreover, the findings demonstrated the importance of taking the Scope 3 emissions into account when analysing the carbon footprints of HEIs, because carbon emissions related to Scopes 2 and 3 correspond to the major portion of total emissions of the sector. For example, emissions associated with commuting by employees and students are often considered a significant carbon emitter, but are not always included as they are optional.

Therefore, after this review, it can be concluded that there are no standardised criteria for reporting the GHG emissions of universities or higher education centres, mainly with regard to aspects related to organisational boundaries for scope 3 emissions and emission factors. The absence of common criteria results in inventories that, apart from problems of comparability, do not indicate clearly the possible opportunities for mitigation actions.

For this reason, and as a futures research proposal, it is necessary to develop methodologies and a simplified tool for calculating the carbon footprint of HEI. The goal is to obtain results that can be compared with other universities and that all opportunities for reducing emissions can be identified and considered.

Acknowledgements

The authors are grateful to Ministerio de Ciencia, Innovación y Universidades (Spain) (DPI2017-89451-R and FPU18/02816).

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

• AASHE (2005) Association for the advancement of sustainability in higher education
• ACUPCC (2007) American College and University President’s Climate Commitment
• Almufadi FA, Irfan MA. Initial estimate of the carbon footprint of Qassim university, Saudi Arabia. Int J Appl Eng Res. 2016; 11 :8511–8514. [ Google Scholar ]
• Alshqaqeeq F, Amin Esmaeili M, Overcash M, Twomey J. Quantifying hospital services by carbon footprint: a systematic literature review of patient care alternatives. Resour Conserv Recycl. 2020 doi: 10.1016/j.resconrec.2019.104560. [ CrossRef ] [ Google Scholar ]
• Alvarez S, Blanquer M, Rubio A. Carbon footprint using the compound method based on financial accounts. The case of the School of Forestry Engineering, Technical University of Madrid. J Clean Prod. 2014; 66 :224–232. doi: 10.1016/j.jclepro.2013.11.050. [ CrossRef ] [ Google Scholar ]
• Baboulet O, Lenzen M. Evaluating the environmental performance of a university. J Clean Prod. 2010; 18 :1134–1141. doi: 10.1016/j.jclepro.2010.04.006. [ CrossRef ] [ Google Scholar ]
• Bailey G, LaPoint T. Comparing greenhouse gas emissions across Texas universities. Sustain. 2016; 8 :1–24. doi: 10.3390/su8010080. [ CrossRef ] [ Google Scholar ]
• Barros MV, da Silva BPA, Piekarski CM, et al. Carbon footprint of transportation habits in a Brazilian university. Environ Qual Manag. 2018; 28 :139–148. doi: 10.1002/tqem.21578. [ CrossRef ] [ Google Scholar ]
• Beardsley R, Morton S. Determining the greenhouse-gas impact of university-sponsored air travel. Am Soc Eng Educ. 2009; 14 :437. [ Google Scholar ]
• Brade W, Brade E. Carbon (CO<inf>2</inf>)-footprint for milk and milk products (review) Tierarztl Umsch. 2014; 69 :167–176. [ Google Scholar ]
• Budihardjo MA, Syafrudin S, Putri SA, et al. Quantifying carbon footprint of Diponegoro University: non-academic sector. IOP Conf Ser Earth Environ Sci. 2020 doi: 10.1088/1755-1315/448/1/012012. [ CrossRef ] [ Google Scholar ]
• Butt ZH. Greenhouse gas inventory at an institution level: a case study of Massey University, New Zealand. Greenh Gas Meas Manag. 2012; 2 :178–185. doi: 10.1080/20430779.2012.760157. [ CrossRef ] [ Google Scholar ]
• CA-CP (2020) Clean air cool planet carbon calculator
• CC (2015) Carbon commitment
• Chung CY, Miaw CL, Huang YC, et al. Investigation of carbon footprint on campus—a case study of Tajen University. Adv Mater Res. 2014; 962–965 :1495–1499. doi: 10.4028/www.scientific.net/AMR.962-965.1495. [ CrossRef ] [ Google Scholar ]
• Clabeaux R, Carbajales-Dale M, Ladner D, Walker T. Assessing the carbon footprint of a university campus using a life cycle assessment approach. J Clean Prod. 2020; 273 :122600. doi: 10.1016/j.jclepro.2020.122600. [ CrossRef ] [ Google Scholar ]
• COM 640 (2019) The European Green Deal. Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions
• COM 80 (2020) Regulation of the European Parliament and the Council establishing the framework for achieving climate neutrality and amending Regulation (EU) 2018/1999 (European Climate Law)
• Copernicus (1993) Cre-Copernicus University Charta
• Cordero EC, Centeno D, Todd AM. The role of climate change education on individual lifetime carbon emissions. PLoS ONE. 2020; 15 :1–23. doi: 10.1371/journal.pone.0206266. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
• Cornejo PK, Santana MVE, Hokanson DR, et al. Carbon footprint of water reuse and desalination: a review of greenhouse gas emissions and estimation tools. J Water Reuse Desalin. 2014; 4 :238–252. doi: 10.2166/wrd.2014.058. [ CrossRef ] [ Google Scholar ]
• Criollo NP, Superior E, Superior E, et al (2019) The role of higher education institutions regarding climate change: the case of Escuela superior politécnica del litoral and its carbon footprint in Ecuador. In: International mechanical engineering congress and exposition IMECE2019. pp 1–10
• CRUE (2002) Sectorial commission on CRUE sustainability
• Durojaye O, Laseinde T, Oluwafemi I (2020) A descriptive review of carbon footprint
• EIO-LCA (2020) Economic input-output life cycle assessment
• Fenner AE, Kibert CJ, Woo J, et al. The carbon footprint of buildings: a review of methodologies and applications. Renew Sustain Energy Rev. 2018; 94 :1142–1152. doi: 10.1016/j.rser.2018.07.012. [ CrossRef ] [ Google Scholar ]
• Filimonau V, Archer D, Bellamy L, et al. The carbon footprint of a UK University during the COVID-19 lockdown. Sci Total Environ. 2021; 756 :143964. doi: 10.1016/j.scitotenv.2020.143964. [ PubMed ] [ CrossRef ] [ Google Scholar ]
• GHG Protocol (2004) The greenhouse gas protocol
• Gómez N, Cadarso MÁ, Monsalve F. Carbon footprint of a university in a multiregional model: the case of the University of Castilla-La Mancha. J Clean Prod. 2016; 138 :119–130. doi: 10.1016/j.jclepro.2016.06.009. [ CrossRef ] [ Google Scholar ]
• GreenMetric U (2010) UI GreenMetric world university ranking on sustainability
• Grimm D, Weiss D, Erek K, Zarnekow R (2014) Product carbon footprint and life cycle assessment of ICT—literature review and state of the art. In: Proceedings of the Annual Hawaii international conference on system sciences. pp 875–884
• Gu Y, Wang H, Xu J, et al. Quantification of interlinked environmental footprints on a sustainable university campus: a nexus analysis perspective. Appl Energy. 2019; 246 :65–76. doi: 10.1016/j.apenergy.2019.04.015. [ CrossRef ] [ Google Scholar ]
• Güereca LP, Torres N, Noyola A. Carbon Footprint as a basis for a cleaner research institute in Mexico. J Clean Prod. 2013; 47 :396–403. doi: 10.1016/j.jclepro.2013.01.030. [ CrossRef ] [ Google Scholar ]
• GUPES (2012) Global universities partnership on environment for sustainability
• Heinonen J, Ottelin J, Ala-Mantila S, et al. Spatial consumption-based carbon footprint assessments—a review of recent developments in the field. J Clean Prod. 2020 doi: 10.1016/j.jclepro.2020.120335. [ CrossRef ] [ Google Scholar ]
• IELab (2020) Australian ecology laboratory
• IPCC Guidelines (2006) Guideliness for national greenhouse gas inventories. General guidance and reporting
• ISCN (2007) International sustainable campus network
• Iskandar J, Rahma N, Rosnarti D, Purnomo AB. The carbon footprint of Trisakti University’s campus in Jakarta, Indonesia. IOP Conf Ser Earth Environ Sci. 2020; 452 :1–9. doi: 10.1088/1755-1315/452/1/012103. [ CrossRef ] [ Google Scholar ]
• ISO/TR 14069 (2013) Greenhouse gases. quantification and reporting of greenhouse gas emissions for organizations. guidance for the application of ISO 14064–1
• ISO 14040 (2006) Environmental management. life cycle assessment. principles and framework
• ISO 14064–1 (2006) Greenhouse gases—specification with guidance at the organizational level for quantification and reporting of greenhouse gas emissions and removals
• Jarillo MP, Pedraza L, Ger PM, Bocos E. Challenges of online higher education in the face of the sustainability objectives of the united nations: carbon footprint, accessibility and social inclusion. Sustain. 2019; 11 :1–15. doi: 10.3390/su11205580. [ CrossRef ] [ Google Scholar ]
• Jung J, Ha G, Bae K. Analysis of the factors affecting carbon emissions and absorption on a university campus—focusing on Pusan National University in Korea. Carbon Manag. 2016; 7 :55–65. doi: 10.1080/17583004.2016.1166426. [ CrossRef ] [ Google Scholar ]
• Kandananond K. The greenhouse gas gccounting of a public organization: the case of a public university in Thailand. Energy Procedia. 2017; 141 :672–676. doi: 10.1016/j.egypro.2017.11.091. [ CrossRef ] [ Google Scholar ]
• Klein-Banai C, Theis TL, Brecheisen TA, Banai A. A Greenhouse gas inventory as a measure of sustainability for an urban public research university. Environ Pract. 2010; 12 :35–47. doi: 10.1017/S1466046609990524. [ CrossRef ] [ Google Scholar ]
• Kulsuwan P, Sirisathit P, Srisuwan C. The carbon footprint assessment from electricity of undergraduate students at Mahidol University Amnatcharoen Campus for Eco University. Int J Agric Technol. 2019; 15 :925–932. [ Google Scholar ]
• Kyoto Protocol (2008) Kyoto Protocol. Reference manual. On accounting of emissions and assigned amount
• Laingoen O, Kongkratoke S, Dokmaingam P. Energy consumption and greenhouse gas emission evaluation scenarios of Mea Fah Luang University. MATEC Web Conf. 2016; 77 :1–5. doi: 10.1051/matecconf/20167706007. [ CrossRef ] [ Google Scholar ]
• Larsen HN, Pettersen J, Solli C, Hertwich EG. Investigating the carbon footprint of a university—the case of NTNU. J Clean Prod. 2013; 48 :39–47. doi: 10.1016/j.jclepro.2011.10.007. [ CrossRef ] [ Google Scholar ]
• Letete TCM, Mungwe NW, Guma M, Marquard A (2011) Carbon footprint of the University of Cape Town. J Energy South Africa 22:2–12. 10.17159/2413-3051/2011/v22i2a3208
• Mendoza-Flores R, Quintero-Ramírez R, Ortiz I. The carbon footprint of a public university campus in Mexico City. Carbon Manag. 2019; 10 :501–511. doi: 10.1080/17583004.2019.1642042. [ CrossRef ] [ Google Scholar ]
• Moerschbaecher M, Day JW. The greenhouse gas inventory of Louisiana State University: a case study of the energy requirements of public higher education in the United States. Sustainability. 2010; 2 :2117–2134. doi: 10.3390/su2072117. [ CrossRef ] [ Google Scholar ]
• Naderipour A, Abdul Z, Rai M, et al. Assessment of carbon footprint from transportation, electricity, water, and waste generation: towards utilisation of renewable energy sources. Clean Technol Environ Policy. 2021; 23 :183–201. doi: 10.1007/s10098-020-02017-4. [ CrossRef ] [ Google Scholar ]
• Navarro A, Puig R, Fullana-i-palmer P. Science of the total environment product vs corporate carbon footprint: some methodological issues. A case study and review on the wine sector. Sci Total Environ. 2017; 581–582 :722–733. doi: 10.1016/j.scitotenv.2016.12.190. [ PubMed ] [ CrossRef ] [ Google Scholar ]
• Nijdam D, Rood T, Westhoek H. The price of protein: Review of land use and carbon footprints from life cycle assessments of animal food products and their substitutes. Food Policy. 2012; 37 :760–770. doi: 10.1016/j.foodpol.2012.08.002. [ CrossRef ] [ Google Scholar ]
• Nilsson AE, Aragonés MM, Torralvo FA, et al. A review of the carbon footprint of Cu and Zn production from primary and secondary sources. Minerals. 2017; 7 :1–12. doi: 10.3390/min7090168. [ CrossRef ] [ Google Scholar ]
• Ologun OO, Wara ST (2014) Carbon footprint evaluation and reduction as a climate change mitigation tool—case study of federal university of agriculture abeokuta, Ogun State, Nigeria. Int J Renew Energy Res 4:176–181. 10.20508/ijrer.74872
• Onat NC, Kucukvar M. Carbon footprint of construction industry: a global review and supply chain analysis. Renew Sustain Energy Rev. 2020; 124 :109783. doi: 10.1016/j.rser.2020.109783. [ CrossRef ] [ Google Scholar ]
• Ozawa-Meida L, Brockway P, Letten K, et al. Measuring carbon performance in a UK University through a consumption-based carbon footprint: De Montfort University case study. J Clean Prod. 2013; 56 :185–198. doi: 10.1016/j.jclepro.2011.09.028. [ CrossRef ] [ Google Scholar ]
• PAS 2050 (2011) Specification for the assessment of the life cycle greenhouse gas emissions of goods and services
• PAS 2060 (2014) Specification for the demonstration of carbon neutrality. Br Stand Inst
• Pérez-Neira D, Rodríguez-Fernández MP, Hidalgo-González C. The greenhouse gas mitigation potential of university commuting: a case study of the University of León (Spain) J Transp Geogr. 2020; 82 :102550. doi: 10.1016/j.jtrangeo.2019.102550. [ CrossRef ] [ Google Scholar ]
• Pirlo G. Cradle-to-farmgate analysis of milk carbon footprint: a descriptive review. Ital J Anim Sci. 2012; 11 :109–118. doi: 10.4081/ijas.2012.e20. [ CrossRef ] [ Google Scholar ]
• Pre Consultants (2019) SimaPro software
• Purwanto A, Syafrudin S, Sunarsih S (2019) Carbon footprint from settlement activities : a literature review. 2001:1–5
• Quintero-Núñez M, López-Millán MC, Bisegna F, et al. Carbon and ecological footprints: tools for measuring the sustainability of the Institute of Engineering at the UABC, Mexicali, BC, Mexico. WIT Trans Ecol Environ. 2015; 199 :3–13. doi: 10.2495/RAV150011. [ CrossRef ] [ Google Scholar ]
• Rao P, Krishnamurthy S, Pradhan V (2017) Commuters’ carbon footprints: a sustainability case study from Symbiosis International University, India. In: Higher Education Institutions in a Global Warming World—The transition of Higher Education Institutions to a Low Carbon Economy. pp 37–57
• Ridhosari B, Rahman A. Carbon footprint assessment at Universitas Pertamina from the scope of electricity, transportation, and waste generation: toward a green campus and promotion of environmental sustainability. J Clean Prod. 2020; 246 :119172. doi: 10.1016/j.jclepro.2019.119172. [ CrossRef ] [ Google Scholar ]
• Riedy C, Daly J. Targeting a low-carbon university: a greenhouse gas reduction target for the Australian Technology Network of Universities. Univ Clim Chang. 2010; 1 :151–162. doi: 10.1007/978-3-642-10751-1. [ CrossRef ] [ Google Scholar ]
• Rizan C, Steinbach I, Nicholson R, et al. The carbon footprint of surgical operations: a systematic review. Ann Surg. 2020; 272 :986–995. doi: 10.1097/SLA.0000000000003951. [ PubMed ] [ CrossRef ] [ Google Scholar ]
• Robinson O, Kemp S, Williams I. Carbon management at universities: a reality check. J Clean Prod. 2015; 106 :109–118. doi: 10.1016/j.jclepro.2014.06.095. [ CrossRef ] [ Google Scholar ]
• Robinson OJ, Tewkesbury A, Kemp S, Williams ID. Towards a universal carbon footprint standard: a case study of carbon management at universities. J Clean Prod. 2018; 172 :4435–4455. doi: 10.1016/j.jclepro.2017.02.147. [ CrossRef ] [ Google Scholar ]
• Rodríguez-Andara A, Río-Belver RM, García-Marina V. Sustainable university institutions: Determination of gases greenhouse efect in a university center and strategies to decrease them. Dyna. 2020; 95 :47–53. doi: 10.6036/9247. [ CrossRef ] [ Google Scholar ]
• Rugani B, Vázquez-rowe I, Benedetto G, Benetto E. A comprehensive review of carbon footprint analysis as an extended environmental indicator in the wine sector. J Clean Prod. 2013; 54 :61–77. doi: 10.1016/j.jclepro.2013.04.036. [ CrossRef ] [ Google Scholar ]
• Sangwan KS, Bhakar V, Arora V, Solanki P. Measuring carbon footprint of an Indian university using life cycle assessment. Procedia CIRP. 2018; 69 :475–480. doi: 10.1016/j.procir.2017.11.111. [ CrossRef ] [ Google Scholar ]
• Santovito RF, Abiko AK. Recommendations for preparation of anthropogenic greenhouse gases emission inventory for University Campuses. World Sustain Ser. 2018 doi: 10.1007/978-3-319-76885-4_19. [ CrossRef ] [ Google Scholar ]
• Schwartz Y, Raslan R, Mumovic D. The life cycle carbon footprint of refurbished and new buildings—a systematic review of case studies. Renew Sustain Energy Rev. 2018; 81 :231–241. doi: 10.1016/j.rser.2017.07.061. [ CrossRef ] [ Google Scholar ]
• Schwarz M, Bonhotal J. Carbon footprint of a university compost facility: case study of Cornell farm services. Compost Sci Util. 2018; 26 :128–143. doi: 10.1080/1065657X.2018.1438934. [ CrossRef ] [ Google Scholar ]
• Sinha P, Schew WA, Sawant A, et al. Greenhouse gas emissions from U.S. institutions of higher education. J Air Waste Manag Assoc. 2010; 60 :568–573. doi: 10.3155/1047-3289.60.5.568. [ PubMed ] [ CrossRef ] [ Google Scholar ]
• Sippel M, Meyer D, Scholliers N. What about greenhouse gas emissions from students? An analysis of lifestyle and carbon footprints at the University of Applied Science in Konstanz, Germany. Carbon Manag. 2018; 9 :201–211. doi: 10.1080/17583004.2018.1440851. [ CrossRef ] [ Google Scholar ]
• Song G, Che L, Zhang S. Carbon footprint of a scientific publication: a case study at Dalian University of Technology, China. Ecol Indic. 2016; 60 :275–282. doi: 10.1016/j.ecolind.2015.06.044. [ CrossRef ] [ Google Scholar ]
• STARS (2013) Sustainability monitoring, assessment and rating system
• Stephan A, Muñoz S, Healey G, Alcorn J. Analysing material and embodied environmental flows of an Australian university—towards a more circular economy. Resour Conserv Recycl. 2020; 155 :104632. doi: 10.1016/j.resconrec.2019.104632. [ CrossRef ] [ Google Scholar ]
• Sun YY, Cadarso MA, Driml S. Tourism carbon footprint inventories: a review of the environmentally extended input-output approach. Ann Tour Res. 2020; 82 :102928. doi: 10.1016/j.annals.2020.102928. [ CrossRef ] [ Google Scholar ]
• Syafrudin S, Zaman B, Budihardjo MA, et al. Carbon footprint of academic activities: a case study in Diponegoro University. IOP Conf Ser Earth Environ Sci. 2020; 448 :012008. doi: 10.1088/1755-1315/448/1/012008. [ CrossRef ] [ Google Scholar ]
• TD (1990) Talloires declaration
• THE (2004) Times higher education—World University Ranking
• Thurston M, Eckelman MJ. Assessing greenhouse gas emissions from university purchases. Int J Sustain High Educ. 2011; 12 :225–235. doi: 10.1108/14676371111148018. [ CrossRef ] [ Google Scholar ]
• Townsend J, Barrett J. Exploring the applications of carbon footprinting towards sustainability at a UK university: reporting and decision making. J Clean Prod. 2015; 107 :164–176. doi: 10.1016/j.jclepro.2013.11.004. [ CrossRef ] [ Google Scholar ]
• Ullah I, Islam-Ud-Din HU, et al. Carbon footprint as an environmental sustainability indicator for a higher education institution. Int J Glob Warm. 2020; 20 :277–298. doi: 10.1504/IJGW.2020.107147. [ CrossRef ] [ Google Scholar ]
• Umberto (2020) LCA software—Umberto LCA
• Varón-hoyos M, Osorio-tejada J, Morales-pinzón T, et al. Carbon footprint of a university campus from Colombia. Carbon Manag. 2021 doi: 10.1080/17583004.2021.1876531. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
• Vásquez L, Iriarte A, Almeida M, Villalobos P. Evaluation of greenhouse gas emissions and proposals for their reduction at a university campus in Chile. J Clean Prod. 2015; 108 :924–930. doi: 10.1016/j.jclepro.2015.06.073. [ CrossRef ] [ Google Scholar ]
• Wahid MFHC. Review on the method for carbon footprint calculation of highway development. Rev Method Carbon Footprint Calc Highway Dev. 2019 doi: 10.1088/1757-899X/513/1/012001. [ CrossRef ] [ Google Scholar ]
• Yañez P, Sinha A, Vásquez M. Carbon footprint estimation in a university campus: evaluation and insights. Sustain. 2020; 12 :1–15. doi: 10.3390/SU12010181. [ CrossRef ] [ Google Scholar ]
• Yazdani Z, Talkhestan GA, Kamsah MZ. Assessment of carbon footprint at University Technology Malaysia (UTM) Appl Mech Mater. 2013; 295–298 :872–875. doi: 10.4028/www.scientific.net/AMM.295-298.872. [ CrossRef ] [ Google Scholar ]

• Share full article

Advertisement

Supported by

Guest Essay

Worrying About Your Carbon Footprint Is Exactly What Big Oil Wants You to Do

By Auden Schendler

Mr. Schendler is the senior vice president of sustainability at the Aspen Skiing Company, the chairman of the board of the group Protect Our Winters and the author of “Getting Green Done.”

Everybody’s going carbon neutral these days , from the big boys — Amazon, Microsoft, Unilever, Starbucks, JetBlue — to your favorite outdoor brand , even ski resorts . Probably your neighborhood coffee roaster , too.

What’s not to like? Becoming carbon neutral means cutting greenhouse gas emissions as much as you can, then offsetting what you can’t avoid with measures like tree planting. Seems admirable.

Well, not exactly. Carbon neutrality doesn’t achieve any sort of systemic change. A coal-powered business could be entirely carbon neutral as long as it stops some landfill gas in Malaysia from entering the atmosphere equal to the emissions it’s still releasing. American fossil fuel dependence would remain intact, and planet-warming emissions would continue to rise. The only way to fix that is through politics, policymakers and legislation. But distressingly, most businesses don’t want to play in that arena.

Instead, they’re doing exactly what the fossil fuel industry wants: staying in their lane, accepting some blame for a global problem and maintaining the dominance of fossil fuels. They’re well intentioned, sure, but also clueless, even complicit.

Imagine if businesses put as much effort into climate lobbying as climate neutrality. Corporations wield tremendous influence over the political system. But on climate, most have decided to sit this one out. Notably, the five biggest tech corporations — Apple, Microsoft, Facebook, Alphabet and Amazon — spend only 4 percent of their lobbying dollars on climate, according to Influence Map .

As a result, they avoid the chance to put in place systemic solutions in favor of carbon-neutral navel-gazing. Large corporations will protest, saying that they are lobbying on climate. But they are typically working both sides of the aisle. And their political contributions are mostly going in the wrong direction. Bloomberg Green examined political donations by more than 100 major American corporations and found last year that they were “throwing their support behind lawmakers who routinely stall climate legislation.”

Climate never ascends to the level of mission-critical issues like trade policy and taxation. Sure, there are exceptions: Salesforce recently said it would intensify its focus on climate lobbying. And Patagonia has always been aggressive, along with Ben & Jerry’s. But they are anomalies, led or inspired by charismatic founders.

How did it come to this? The story of how what’s considered the best approach to corporate sustainability became complicity with the very industry responsible for climate change starts with the famous “Crying Indian” commercial of the 1970s. The ad, in which an actor portraying a Native American is devastated by the sight of rampant pollution, created several generations of dutiful litter-picker-uppers. (Guilty!) But it wasn’t so benign. It was, in fact, masterly propaganda from the beverage and container industries, designed to place responsibility for the trash problem on American consumers, not manufacturers.

The approach was so good that the fossil fuel industry adopted the very same strategy.

In 2004, BP hired the public relations firm Ogilvy & Mather to improve its image, in part by conveying the message that consumers of oil and natural gas bear the responsibility for their greenhouse gas emissions, not the producers of the oil and gas they use. The result was BP’s ingenious carbon footprint calculator , which allows individuals to calculate the carbon emissions that result from their activities. It’s “about helping you to go carbon neutral — reducing and offsetting your carbon footprint,” BP says on its “target neutral” website.

Nor was BP alone among the big oil companies communicating this message. A study by Naomi Oreskes and Geoffrey Supran at Harvard published in May in the journal One Earth found that since 1972, ExxonMobil has consistently used “rhetoric aimed at shifting responsibility for climate change away from itself and onto consumers.”

Yes, those consumers want the hot showers, warm homes and cold beer that coal, oil and gas provide. But they did not insist on the burning of fossil fuels for those amenities. Now there are other ways to produce energy, and responsibility to tap those renewable resources lies with the world’s energy companies.

Today, almost 20 years after BP’s carbon calculator went live, reducing a firm’s carbon footprint is still the gold standard of corporate climate action. The phrase is firmly lodged in the environmental lexicon.

The idea of offsetting one’s carbon footprint by cutting or eliminating greenhouse gas emissions in one place to make up for emissions elsewhere has grown into an enormous industry. Businesses often do this by buying carbon credits to offset emissions they can’t or won’t reduce. The consulting firm McKinsey estimates that “the market for carbon credits could be worth upward of $50 billion in 2030.”

Many of these offsets underwrite worthwhile projects — protecting virgin expanses in some of the world’s last great forests, as in the Amazon, or the deployment of solar power. But according to an analysis by the private-sector Taskforce on Scaling Voluntary Carbon Markets, fewer than 5 percent of offsets in 2020 removed carbon dioxide from the atmosphere.

Which, of course, is what we desperately need to be doing.

A giant, systemic problem like climate needs to be addressed like other huge environmental challenges the world has successfully taken on — reducing ozone-depleting chemicals worldwide, for example, and sharply cutting back on smog and water pollution in the United States. Imagine if, in response to the expansion of the ozone hole, businesses and governments had said, “We’ll just hope businesses do the right thing.” Instead, international policymakers created the Montreal Protocol, which set standards that phased out ozone-destroying chlorofluorocarbon use worldwide.

We need more of that approach — citizens, businesses and governments working together to address this crisis. It might result in policy solutions like government regulation, effective carbon taxes, national standards for renewable energy and electrification, the elimination of legacy subsidies for the fossil fuel industry, strict auto emission standards and new national building codes. All of these approaches threaten fossil fuel’s business model and, not coincidentally, would help to slow the warming of the planet.

What do fossil fuel companies prefer? They like consumers and corporations to do anything and everything as long as they stay out of the companies’ way and avoid doing anything that could actually make a difference.

Tragically, the overwhelming majority of American businesses are on a path of complicity. Their climate strategy avoids conflict and generates great public relations. Unfortunately, it also allows fossil fuel interests to monetize their remaining assets unhindered, ensuring catastrophe for all.

How carbon neutral is that?

Is one of your favorite places in your country being affected by climate change?

Describe that place — a beloved campsite, the levee you run, a local market, the woods you explored as a child — and tell us in a brief voice mail why you love it: (+01) ‪405-804-1422‬. What does this place mean to you, how is it changing, and how do you feel seeing it reshaped by environmental issues?

We are interested in hearing from the global community. Please include your country code with your phone number in your message so that we can reach you with any questions. We may use a portion of your message in a future article.

Auden Schendler is the senior vice president of sustainability at the Aspen Skiing Company, the chairman of the board of the group Protect Our Winters and the author of “Getting Green Done.”

The Times is committed to publishing a diversity of letters to the editor. We’d like to hear what you think about this or any of our articles. Here are some tips . And here’s our email: [email protected] .

Follow The New York Times Opinion section on Facebook , Twitter (@NYTopinion) and Instagram .

Carbon Footprint of Supply Chains: A Scoping Study (2013)

Chapter: conclusions.

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

6 CONCLUSIONS A review of current tools for measuring the carbon footprint of freight transportation has shown a lack of consistency in scope and methods. The term “carbon footprint” itself is subject to ambiguity, and the focus of many current programs on measuring emissions within an organizational boundary has limited the effectiveness of applying tools to supply chain activities that may span organizational boundaries. Based on the focus of current tools, the need for future consideration of alternative fuel vehicles, and the emerging standards in Europe, a definition that captures all six of the Kyoto greenhouse gases, employs a well-to-wheel focus on emissions, and is focused on the energy consumed in vehicles is recommended. Through performance frameworks drawn from accounting, supply chain performance measurement, and Life Cycle Assessment a set of criteria for evaluating current tools have been proposed. These criteria recognize the needs of tools to improve decision-making internally while providing a means for external reporting and benchmarking. The criteria of depth, breadth, and precision are closely related to the internal decision-making process, as the output of a tool is relevant only if it captures the necessary scope and precision required to make a particular decision. The criteria of comparability and verifiability are drawn from principles of external reporting. Comparability is necessary if the results of the tool are to be used to compare across organizations or time periods, while verifiability helps assure that the results of the tool are a faithful representation of the claims. This latter characteristic is necessary given the difficult of directly verifying claims regarding carbon emissions. A workshop was conducted at MIT that brought together a number of stakeholders to evaluate and verify the proposed criteria. Using the Analytic Hierarchy Process the participants in the workshop rated the importance of the different criteria. The results of this exercise were used to provide relative weights for the criteria to be used in an evaluation of current programs. A number of current programs were then rated on a high-medium-low scale for each of the five criteria, and the weightings of the criteria were used to generate a quantitative evaluation of the tools. The results of this process produced high scores for two different types of tools: tools focused on a single mode that provided consistent boundaries to capture the performance of specific carriers and tools that applied a consistent process across all modes, at the cost of a level of precision. Based on the results of this process a future tool should have the capability to provide a consistent boundary and process across all four main modes of transport, while having the ability to capture carrier-specific performance that can be used by shippers in their decision-making process. A work plan and timeline were developed for two possible versions of a future tool. The basic tool provides a consistent set of emissions factors that capture the scope of the supply chain recommended in this work. This tool could be quickly developed, 85

with the main focus of the work developing a consistent set of emissions factors. The more advanced tool would add more advanced capabilities and a better user interface, with the primary functional improvement of capturing user data to created updated carrier or route-specific emissions factors for use by other organizations. A series of example scenarios were provided to help clarify issues in tool development by illustrating issues related to determining emissions factors and performing calculations. 86

TRB’s National Cooperative Freight Research Program (NCFRP) Web-Only Document 5: Carbon Footprint of Supply Chains: A Scoping Study defines a standardized, conceptual approach to assessing global greenhouse gas (GHG) emissions of the transportation component of supply chains, critiques current methods and data used to quantify greenhouse gas (GHG) emissions, and outlines a work plan to develop a decision tool to help estimate the carbon footprint of the transportation component of supply chains.

READ FREE ONLINE

Welcome to OpenBook!

You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

Do you want to take a quick tour of the OpenBook's features?

Show this book's table of contents , where you can jump to any chapter by name.

...or use these buttons to go back to the previous chapter or skip to the next one.

Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

To search the entire text of this book, type in your search term here and press Enter .

Share a link to this book page on your preferred social network or via email.

View our suggested citation for this chapter.

Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

Get Email Updates

Do you enjoy reading reports from the Academies online for free ? Sign up for email notifications and we'll let you know about new publications in your areas of interest when they're released.

News from the Columbia Climate School

The 35 Easiest Ways to Reduce Your Carbon Footprint

In the face of the recent   National Climate Assessment report on the threats of climate change, the Trump administration continues to try to roll back environmental policies. Individuals, however, can make a difference by reducing their personal greenhouse gas emissions. While there are many ways to do this and save energy—such as insulating your home, putting up solar panels, and planting trees—the following are the simplest and easiest changes you can make. They require little effort or financial investment.

First calculate your carbon footprint

Your carbon footprint is the amount of greenhouse gases—including carbon dioxide, methane, nitrous oxide, fluorinated gases and others—that you produce as you live your life. The Deep Decarbonization Pathways Project  determined that in order to hold the global temperature rise to 2˚C or less, everyone on earth will need to average an annual carbon footprint of 1.87 tons by 2050. Currently, the average U.S. per capita carbon footprint is 18.3 tons. By comparison, China’s per capita carbon emissions are 8.2 tons. We all have a ways to go to get to 1.87 tons.

Calculate your carbon footprint at carbonfootprint.com to find out how you’re doing. The EPA’s carbon footprint calculator can show how much carbon and money you will save by taking some of these steps.

Here are some of the easiest ways you can start to shrink your carbon footprint.

1. Eat low on the food chain. This means eating mostly fruits, veggies, grains, and beans. Livestock —meat and dairy—is responsible for 14.5 percent of manmade global greenhouse gas emissions, mainly from feed production and processing and the methane (25 times more potent than CO2 at trapping heat in the atmosphere over 100 years) that beef and sheep belch out. Every day that you forgo meat and dairy, you can reduce your carbon footprint by 8 pounds—that’s 2,920 pounds a year. You can start by joining Meatless Mondays .

2. Choose organic and local foods that are in season. Transporting food from far away, whether by truck, ship, rail or plane, uses fossil fuels for fuel and for cooling to keep foods in transit from spoiling.

3. Buy foodstuffs in bulk when possible using your own reusable container.

4. Reduce your food waste by planning meals ahead of time, freezing the excess and reusing leftovers.

5. Compost your food waste if possible. (If you live in New York City, you can find a compost drop-off site here.

6. Don’t buy fast fashion. Trendy, cheap items that go out of style quickly get dumped in landfills where they produce methane as they decompose. Currently, the average American discards about 80 pounds of clothing each year, 85 percent of which ends up in landfills. In addition, most fast fashion comes from China and Bangladesh, so shipping it to the U.S. requires the use of fossil fuels. Instead, buy quality clothing that will last.

7. Even better, buy vintage or recycled clothing at consignment shops.

8. Wash your clothing in cold water. The enzymes in cold water detergent are designed to clean better in cold water. Doing two loads of laundry weekly in cold water instead of hot or warm water can save up to 500 pounds of carbon dioxide each year.

9. Buy less stuff! And buy used or recycled items whenever possible.

10. Bring your own reusable bag when you shop.

11. Try to avoid items with excess packaging.

12. If you’re in the market for a new computer, opt for a laptop instead of a desktop . Laptops require less energy to charge and operate than desktops.

13. If shopping for appliances, lighting, office equipment or electronics, look for Energy Star products , which are certified to be more energy efficient.

14. Support and buy from companies that are environmentally responsible and sustainable.

15. Do an energy audit of your home. This will show how you use or waste energy and help identify ways to be more energy efficient.

16. Change incandescent light bulbs (which waste 90 percent of their energy as heat) to light emitting diodes (LEDs). Though LEDs cost more, they use a quarter of the energy and last up to 25 times longer. They are also preferable to compact fluorescent lamp (CFL) bulbs, which emit 80 percent of their energy as heat and contain mercury.

17. Switch lights off when you leave the room and unplug your electronic devices when they are not in use.

18. Turn your water heater down to 120˚F. This can save about 550 pounds of CO2 a year.

19. Installing a low-flow showerhead to reduce hot water use can save 350 pounds of CO2. Taking shorter showers helps, too.

20. Lower your thermostat in winter and raise it in summer. Use less air conditioning in the summer; instead opt for fans, which require less electricity. And check out these other ways to beat the heat without air conditioning.

21. Sign up to get your electricity from clean energy through your local utility or a certified renewable energy provider. Green-e.org can help you find certified green energy providers.

Transportation

Because electricity increasingly comes from natural gas and renewable energy, transportation became the major source of U.S. CO2 emissions in 2017. An average car produces about five tons of CO2 each year (although this varies according to the type of car, its fuel efficiency and how it’s driven). Making changes in how you get around can significantly cut your carbon budget.

22. Drive less. Walk, take public transportation, carpool, rideshare or bike to your destination when possible. This not only reduces CO2 emissions, it also lessens traffic congestion and the idling of engines that accompanies it.

23. If you must drive, avoid unnecessary braking and acceleration. Some studies found that aggressive driving can result in 40 percent more fuel consumption than consistent, calm driving.

24. Take care of your car. Keeping your tires properly inflated can increase your fuel efficiency by three percent; and ensuring that your car is properly maintained can increase it by four percent. Remove any extra weight from the car.

25. When doing errands, try to combine them to reduce your driving.

26. Use traffic apps like Waze  to help avoid getting stuck in traffic jams.

27. On longer trips, turn on the cruise control, which can save gas.

28. Use less air conditioning while you drive, even when the weather is hot.

29. If you’re shopping for a new car, consider purchasing a hybrid or electric vehicle . But do factor in the greenhouse gas emissions from the production of the car as well as its operation. Some electric vehicles are initially responsible for more emissions than internal combustion engine vehicles because of manufacturing impacts; but they make up for it after three years. This app  rates cars based on their mileage, fuel type and emissions from both the production of the car and, if they are EVs, from generating the electricity to run them.

30. If you fly for work or pleasure, air travel is probably responsible for the largest part of your carbon footprint. Avoid flying if possible ; on shorter trips, driving may emit fewer greenhouse gases.

32. Fly nonstop since landings and takeoffs use more fuel and produce more emissions.

33. Go economy class. Business class is responsible for almost three times as many emissions as economy because in economy, the flight’s carbon emissions are shared among more passengers; first class can result in nine times more carbon emissions than economy.

34. If you can’t avoid flying, offset the carbon emissions of your travel.

Carbon offsets

A carbon offset is an amount of money you can pay for a project that reduces greenhouse gases somewhere else. If you offset one ton of carbon, the offset will help capture or destroy one ton of greenhouse gases that would otherwise have been released into the atmosphere. Offsets also promote sustainable development and increase the use of renewable energy.

This calculator estimates the carbon emissions of your flight and the amount of money needed to offset them. For example, flying economy roundtrip from New York to Los Angeles produces 1.5 tons of CO2; it costs $43 to offset this carbon.

You can purchase carbon offsets to compensate for any or all of your other carbon emissions as well.

The money you pay goes towards climate protection projects. Various organizations sponsor these projects. For example, Myclimate funds the purchase of energy efficient cookstoves in Rwanda, installing solar power in the Dominican Republic, and replacing old heating systems with energy efficient heat pumps in Switzerland. Cotap  sustainably plants trees in India, Malawi, Mozambique, Uganda and Nicaragua to absorb CO2; you can sign up for monthly offsets here. Terrapass  funds U.S. projects utilizing animal waste from farms, installing wind power, and capturing landfill gas to generate electricity. It also offers a monthly subscription for offsets.

Get politically active

35. Finally—and perhaps most importantly since the most effective solutions to climate change require governmental action— vote! Become politically active and let your representatives know you want them to take action to phase out fossil fuels use and decarbonize the country as fast as possible.

Related Posts

A Virtual Reality Film That Makes the Climate Crisis Feel “Real”

Key Ocean Current Contains a Warning on Climate

Using Nature to Help the Climate: 4 Ways That Work

Celebrate over 50 years of Earth Day with us all month long! Visit our Earth Day website for ideas, resources, and inspiration.

thank you for this information, I do my share but could improve. As the richest people on earth use more carbon their should pay carbon tax.

I do agree with you Kalpna, the richest people use an average of 1000x times more (the richer the more they use), since they have mansions (requires a lot more power), boats, private aeroplanes etc. Their Co2 emissions are through the roof, so carbon tax for the rich (especially ultra rich) would go a huge way to offsetting their extravagant lifestyles and the world in general and wouldn’t even impact them hardly at all.

Gee, I wonder how they got a million dollars, oh wait, because they work. And give others work. And TAX THEM? For what, they work hard and give others work and raising taxes is not ther answer, but lowering them is. But i guess its nice to have inflation and poverty, because of CO2. (My humble opinion.

Humble is down to Earth, not exploiting others for the sake of acquiring more to fill one’s voracious consumerism habits. Taxing a high carbon consumption lifestyle sounds responsible and humble to me and I think it spiritually solid to create a carbon tax on all that we do to help bring our awareness and consumerism disease to a more humble place.

Paying for your mistakes doesnt solve the problem. The biggest contributors pay so that people in poor countries end up changing their habits and end up planting more trees to compensate for the habits of the rich. This is not just nor climate justice. The perpetrators need to change their habits, their governments should govern their spending habits better.

Just because a person has wealth does not mean that they live extravagantly. That is an assumed generalization. Why don’t we say tax the mansion, not anyone “wealthy enough to own one.” Some people of means Do choose simple lifestyles. Why punish them simply because they have the financial resources to be extravagant?

Yeah, there should be rules for emitting Co2 (like your electric reading shouldn’t be above a reasonable number) or there’ll be fines. Taxes will be for the extra emitters, like the rich people. Taxes depend on their wealth and how much they emit.

Agreed. Taxes these days are getting harder to pay and by the time I’m dead, we will probably still have a lot of carbon dioxide in the atmosphere. But then again, some things DO need carbon dioxide to live.

PGE CA is starting to make customers more aware of electric usage via monthly comparisons of your home’s usage versus more acceptable usage based on a number of specifications. Rates are also increasing based on when it’s more expensive to use during a 24 hour period. Our high rate time is 4-9PM

All these rich people don’t even care about this Earth. I mean Jeff Bezos went to space! Vladimir Putin has a yacht that’s roughly 2 million dollars. AND THEY DO NOTHING ABOUT IT. They could be helping their home, but children(or people who have been rich their whole lives) don’t understand anything about poverty. And they never will. We need to make a change for the better of humankind.

I totally agree. But also I think you mean $200 million. $2mill wouldn’t even pay for yearly upkeep for super yachts. I know as my friend works on one, and the maintenance costs are over $10mill per year 🙂 Peace.

I always follow your Blogs. They are very informative. I get information about various topics from them. I also want to share my blog with you. You will get information about the Arlo app from it. Thank you

On god, I think that a richer people should be paying carbon tax because they are using much more carbon than lower pay/lower class people

In your list of “ways to reduce your carbon footprint” I notice that you forgot to mention the single most important thing a family can do: have one fewer children. Do I sense fear of stating the unpopular?

Popular or not, you may be wrong because people are both the cause of and solution to all their problems. People are not wolves. With wolves and chickens, the more wolves: the fewer chickens, and the fewer wolves: the more chickens. With people, it is just the opposite: the more people you get more chickens not less. That extra kid may contribute to sustainablility.

I see your viewpoint. If one is living sustainably and encourages other people to do so, the benefits of that person living on the planet (through getting other people to reduce their environmental impact) likely exceeds the personal carbon footprint of that person.

Jim, I agree!

I agree Jim, fewer consumers, polluters, destroyers, less harm to the environment.

Or getting rid of family pet, 30% of CO’3 related to meat production

Family pet = meat production? Benefits of pets is tremendous – safety, assist handicapped, therapy animals, provide comfort and companionship, reduce blood pressure and anxiety, etc .If you are referring to the fact that they eat pet foods, most pet foods are made from meat scraps (parts not sold for human consumption) and include vegetables. Also, changes in feed for farm animals has reduced gas emissions.

I don’t think that a family pet can be produced to meat but you have the right idea

ANIMAL HATER

Lol you all are all for less babies but not for less pets. Lord the internet is funny.

How about we start raising our children to be more earth friendly?? How about we expect companies ( including pet food) to produce in ways that are good for the environment? Why do we need to get rid of kids or pets?

I guess this is an old thread, but birds for instance eat the same things as their vegan owners. We had broccoli spears, edamame beans, a few pasta rotinis, a few spoons of corn kernals, and the parrot had some organic Harrison feed pellets with vitamins, plus a splay of fresh pea pods. I had mung dahl on quinoa later on with kale, he had another round of pellets for dinner, apple juice and pea pods. Parrots need adopting, if anyone wants a good pet, check your computer for parrot rescue or exchange sites. Lots of loving companions that need homes….and they like what we like to eat….bananas and oranges, but mostly local stuff, zuccini and corn this time of year and into fall.

They fear underpopulation spesifically, which is already a danger in places like China & Europe, where the elderly outnumber anyone under 12

Thanks for the tips. However, #32 which advises non-stop flying is unlikely to be true most of the time as non- stop flights tend to burn large quantities of fuel carrying the additional fuel mass. In general a 50/50 split is the most fuel efficient way to take a long flight.

Charge by weight for flying (person + luggage)

Maybe we should consider adding one more idea. #36. Save carbon rich material from turning into CO2. Reduce your carbon footprint by keeping dead plant around longer. A leaf falls on the ground and is decomposed this year. I dry a leaf and put it a book and can be there in 100 years.

This is what the Japanese government does: if you build a house of wood, you get a huge cheque of about $8,000USD from the government for storing CO2 in your house.

Your point about eating less meat, er maybe even going full vegan is incorrect. At the end of the day it doesn’t matter one thing what you eat. Meat might be responsible for more greenhouse gasses, but for vegitarians they cut down millions of acres of forest eacht year to provide the room to grow their crops (Just look at the soy farms in Brazil and the palm olive fields in Malaysia). Deforestation causes far more greenhouse gas emission than cattle, and it also takes away the only means by which CO2 can be removed from the air. This problem is caused by overpopulation, not meat.

We can both agree that deforestation is a big problem for climate change. However, it takes 12 pounds of grain to make 1 pound of beef. It is therefore much more efficient, and requires less land and deforestation, if we just eat the grain itself. It’s like cutting out the middleman, only the middleman = cows 🙂

Other interesting stats here: http://holdthebeef.org/#new-page-4

cows can and do eat grass. Grass is a huge CO2 sink. Buy grass fed. Broccoli will use more land and give you less nutrition. Hooved animals walked this earth in large numbers before humans concentrated them in fences and farms.

I though to make meat all you do is kill and animals, cook it, then eat it…?

Actually 70 to 75% of the world’s soy is used for animal feed for chickens, pigs, cows and farmed fish. After beef, which is #1, soy is the second largest cause of deforestation.

I am a vegan and have solved the problem of soy and palm oil. I don’t use either, and am a healthy vegan.

Solution could be to stop over eating, veg or meat and stop wasting food. I think food industry should also be penalized. One of the culprits in my opinion are supermarkets. They buy cheap and more and waste a lot as their pricing takes wasting into account. Local govt should monitor and penalize if they waste food items and simultaneously reduce the expiry date of the food items, this will deter industry to mass produce anything edible. These are scalable and I believe would be very effective.

Packaging is also a problem. A 750 ml bottle for wine weighs 750 gm – very inefficient. Lots of energy wasted even if recycled. Ban wine, beer, drinks in glass bottles?

I’m an Ag student and I’m actually doing some research for an Ag Issues project for FFA and I noticed that you might be thinking of this the wrong way. I grew up on a commercial cattle ranch and I obviously agree with you that cutting out meat isn’t the way to go. Growing up in a rural farmland area and being a member of FFA I have always thought of the crop industry and the cattle/meat industry as a united industry: the Agricultural Industry. But I of course realize that not everyone has this experience. I don’t know if this is going to make much sense but what I’m trying to say is that this issue is not CROPS vs. MEAT. We as the agricultural industry raise cattle for dairy and meat products AND we grow the crops necessary for people who choose to be either vegan or vegetarian. It’s not really two separate industries that are competing for your attention, it’s only one. I cannot say anything about other places like Brazil and Malaysia but here in the United States, the agricultural industry is CONSTANTLY working to improve our methods of farming and ranching to emit less greenhouse gases into the atmosphere. I would also like to say that I am slightly disappointed in an institution like Columbia University for blaming climate change on cattle burping methane into the atmosphere. Cows do burp methane into the atmosphere, this is true, but what people always seem to forget is that this is a part of the natural carbon cycle. Key word there: NATURAL. These cattle have been doing this since the beginning of ranching methods and before that, the hundreds of thousands of Bison that used to roam the great plains did the same thing. We cannot blame cattle for doing what they are designed to do. Anyway, sorry for rambling on, hope that this possibly helped someone.

Acarnes, this is really poor logic. Cows do “naturally” produce GHGs. But we have 94.8 million cows in the US. That’s almost 1 cow for every 3 people. There is nothing natural about industrial agriculture, and quantity of the GHG source is more important than whether or not it existed in some capacity pre-industrialization. As someone mentioned above, it takes 12 lbs of grain to make 1 lb of beef (not to mention water!). If more people move to substitute more plants for beef, you can feed the same amount of people with less cows, as that 12 lbs of grain can feed more people than 1 lb of beef. This clearly reduces carbon footprint, as it reduces overall consumption and agricultural production per person. This may not be in your best interests as someone going into the Ag industry, which I’m sure informs some of your opinion there, but that doesn’t make it any less true.

hello, the supermarkets wouldnt know what hit them if we all ate less meat, that would reduce in food wastage too, but im sure they would adjust!

Can’t believe anyone would give a thumbs down for facts.

Only 6% of the crop grown on land cleared in Brazil for soya production, goes to feed people. 94% goes to feed animals and chickens to provide food for meat eaters. It takes much less land to feed people directly with plant food than it would to grow the food to feed the animals with which to feed those people. If we all are a vegetarian or vegan diet we would need less land and more could be left as wild forest to absorb and store carbon.

Hey Patric, I just think that your forgetting that we use a large areas to grow crops to then feed live stock, much more then it would take to feed the human population. Also cows produce methane.

they cut down those forests to make room for livestock it takes a lot less room for a vegetarian or vegan diet than one that has meat I am not vegan or vegetarian but you have a thing backwards.

Hi Patric, I definitely see what you are saying with regards to Soy production. Indonesian and Malaysian Rainforest are cut down for both palm oil and soy production. This accounts for around 10% of the problem each, which is still a significant proportion. Beef production, however, is 85% of the problem and a lot of Soy Beans are grown as cattle feed as grazing ground is not possible without the rainforest. This means that beef and dairy production are the huge contributors to climate change as they also include a vast proportion of the requirement for soy. If veganism isn’t for you, you’d be better to switch to white meats such as chicken as they take up less physical space and require less logging or land degradation than beef production (but still have greater carbon and ethical implications than a vegan diet).

Lancet studies in England put out a study. We cannot save the planet unless we stop herding beef. Cows grow for 2 years minimum before industrial harvesting=a lot of methane farts and belches. Ruminants. The study showed less beef and less lamb on the plates of the world to save the planet. Also think of all the heart surgery from grease in our blood vessels these days. Less beef, then less colon cancer too, better health. The surgeon general in the US has stated it, but cattlemen won’t let the warning be printed on the meat packages. Eating red meat has been proved to be hazardous to human health. Lobbyists deny the truth. Big meat is full of toxic material in the animal fat, and big fish too. The meat eaters make vegans pay for their medical bills, which are enormous. Japanese eat dolphin which is loaded with mercury.

It took 150 million years to create the rain forest in Brazil. They should grow river turtles, not cattle, if they want meat in the Amazon. Cows weren’t meant to live on rich fertile forest land, trees live there and have rights to the soil they created via vegetation. It takes 1,000 gallons of water to make a pound of beef meat. Meat eater’s clothing is so hard to clean that maids must make hot, hot water and use lots of toxic soaps.

Why not just live clean? Lots of good nuts and apples to harvest. Tropical people are happy with bananas and peas, pineapple and all that juicy variety. They hardly eat the meat they grow on the fields they have created from destroyed forests. Rice is almost the divine of foods, with ginger and turmeric. Some beans and squash keep the soil good, and healthy soil grows all kinds of fruits and trees. We need good soil.

Cows eat too much before slaughter. If you must eat animal, better to eat rabbits and turtles, frog’s legs and snails. Use some locust “meat” to make your burgers. People can eat sea urchins that overpopulate the shores. People could fish them with a knife. Pig farms will have to close too. All that pollution and putrid decayed matter pigs produce will at last be gone. Farms were once sacred to nature. Soil was fertile, and so plentiful was food. The world was an Eden which will return. Nature has always favored that which really sustains her. There is enough vegan matter to feed all the billions of folks alive today, but it isn’t sourced out well. Too many meat eaters eat too much of it. Almost all of it … via the large industrial cow farms.

Patric, I agree with you at a certain point: Brazil, has and keeps the world largest green are. Only 8% of its territory is used to produce meat, beans, coconuts farms and so on. It is the only country in the world that does somethong to keep his green area. I know about it, I lived 20 years in South America and I know how tough they are regarding keeping their green amazon. I used to work for the government, I used to work with territory planning and development of sustainable activities such as economics based o local vocation and load capacity of the environment.

There is a massive misconception about soy. (77%) Most of the soy grown is used worldwide is used exclusively as animal feed and only 7% is used for direct human consumption. Soy is a great source of nutrients to the human diet. https://ourworldindata.org/soy#:~:text=More%20than%20three-quarters%20%2877%25%29%20of%20global%20soy%20is,as%20tofu%2C%20soy%20milk%2C%20edamame%20beans%2C%20and%20tempeh .

77% of farmland goes to meat. 80% of deforestation goes to livestock. 97% of US soy (which you mentioned) goes to livestock.) The problem is meat.

I’m surprised no one has mentioned that there are alternatives to traditional livestock, and fish for meat/protein. What about bug protein, i.e. cricket ranches and/or the many, many plants that are high in protien that do not use anywhere near the resources of traditional lifestock and crops. There are so many alternatives to growing corn, wheat, and soybeans and raising cattle, chickens, etc. The ag economy is profitable, and the lobbyist are plentiful and powerful. Same as the oil industry. If you want to be a future farmer in America, then thinking way outside of the traditional scope of what is considered farming and ranching must be considered. Innovation in that sector is not all that innovative. Crops and livestock still require enormous amounts of resources, that is inescapable. Buying and growing locally produced food sources can save money and reduce carbon emissions and connects us in our communities. Americans have gotten far from that concept; we all expect that we should be able to go down to the local Wal-Mart and get everything we need. Wal-Mart put all the mom and pop entrepreneurs out of business, and the tax incentives and crop insurance programs developed in the early 1980’s that incentivized growth put a lot of small farming operations out of business, like my own family and many, many farming operations. This concept that we must always be in a financial growth pattern is exactly what is going to cause our own demise.

Hello there! Terrific points about energy conservation and carbon footprint reductions. Props to the author(s)! I happen to run a blog devoted to renewables and energy efficiency and thought one of my articles about energy audit tools might be useful to your readers if you incorporate it in this article.

Here it goes: https://www.everysolarthing.com/blog/energy-audit-tools/ There are no ads or affiliate links whatsoever.

Either way, keep up the important work of spreading a word about environmentally friendly lifestyle.

How can I reduce my carbon footprint and still be warm

Lots of options. Get a programmable thermostat and set it so that you are comfortable but not crazy hot or cold; seal air leaks in your home; add insulation; don’t leave doors & windows open when running furnace or AC; reduce the temperature setting of your hot water heater to 120 F; choose to live close to where you work and shop so that you can walk, ride a bike, or take public transit; show up at public meetings to advocate for mixed use zoning, higher density zoning, public transit; choose renewable energy if your state/city allows you to choose your electricity supplier; eat a bit less beef, switching to a bit more poultry and/or grains, beans, veggies; buy less stuff – take care of what you own, make it last a long time, reuse, repair, use reusable water bottles and coffee cups, don’t waste $ on flashy objects that end up not really bringing you joy. No doubt you and others can think of even more options.

The point is, we don’t need to live hard, cruel lives of depravation to reduce our carbon footprints. A lot can be accomplished through thoughtful choices.

A good old fashioned sweater.

I know people who keep the heat at 80 and wear a T-shirt around inside when its 20 degrees out. Its a reasonable sacrifice to make to live at a comfortable 65, and if you can’t handle that, Goodwill has sweaters for cheap.

buy thrifted clothing !!!

Can you say more about how using reusable bags reduces the carbon footprint please? we are trying to pass a bag ban in my town and need all the solid scientific data we can get.

Going politically active doesn’t necessarily lower your carbon footprint, it can force the entire country’s carbon footprint down, and as a result, yours. For example, if you voted for a law to shut down a coal powered power plant and replace it with a solar or wind farm, you would be cutting down on an entire organization’s carbon footprint, and not just your own.

A plastic bag is equal to about 1 drop of crude oil. Driving to the supermarket consumes at least 10 drops of oil/petrol per kilometre. Bags are litter but driving is much worse for carbon footprint.

not a scientist or anything, but in order to produce single-use plastic bags they have to use crude oil and this produces a lot of greenhouse gases/carbon emissions, and they only get used once! with reusable cloth bags (sometimes people have reusable bags made of other materials), it has a different amount of emissions produced (generally less, if it’s cloth and not plastic) and then this also pays off because you aren’t producing more emissions each time you go shopping because you can reuse the bag. But someone mentioned that cars use more crude oil than a plastic bag, which is true, so walk/ride to the grocery store, or make sure you are running other errands at the same time in order to not waste fuel or anything 🙂 (and buy an EV if u can!)

Thanks a lot for the tips.. by the way, you mention that better to wash in cold water.. what will happen if we wash with warm water?is there any risk?

I don’t think there’s any risk except that it takes energy to heat water, therefore higher carbon footprint

This is very informative always trying to cut down on my impact especially since we never know when we’re gonna need filtered air don’t want it to be in my life time but at this rate it might

We all need to work harder to save our environment

Finally an article that actually lays out what each of us can do. The problem seems so overwhelming.

Yes it may do but all helps even just small things. Just thinking about what we can do will lead to positive changes be it small to start with but may be a big thing in the near future.

I think all of these re great ideas, but to add one, i would like to say that we try to make clothes out of the scraps of cloth that are going to the landfill.

And repair your clothes

Recent gift was a rug made in Scotland from recycled wool.

hello, i am in 4rth grade, and my idea is that we try to get things that will fill the landfill, so when we don’t buy them, they will go to the landfill. when we buy fancy cloths, that is wasting water, which is not good, but old cloths are used, so you are not using new ones!

I see your point but another point of view is, if you start buying the product constantly, the company will produce more, and the more product you make the more Co2 is produced through the factories.

people need to keep protesting in Brazil so the president of Brazil can stop doing bad stuff to the earth

hi i am in 4th grade and i think you should turn of all the light when you leave the house,use self chargers to charge your phones,and have solar panels insted of wasting electricety.

ride a bike or walk if youare going somewere.also if it is a mile drive if ir is less then walk or drive

hi i’m Becca and i’m in 4th grade my idea is i think we need to stop cutting down trees because it uses up a lot of units

we have to try to help the planet

I am wondering about point 12. Do you have any more information about why a laptop should be more efficient than a desktop. I thought its just the same parts put together in a different housing.

Desktops are plugged in so can use whatever power they like and function well. Laptops need to be portable so the longer the battery life, the better. Therefore, a laptop needs to be more eco to increase their sales as people buy laptops with longer battery life.

But you also need to put in mind the performance. If loading a video on a laptop takes 2 hours to upload on a desktop it might take only 45min. Desktops have an amazing performance. Also on a desktop, you can put it in performance mode where the ratios are equwielent.

Laptop components are designed and fabricated to use less power.

Just came upon this site in search of ways I can reduce my own carbon footprint and found some good ideas that I will try to implement. I have found that corporations, in their search of profits, tend to move their manufacturing off shore to jurisdictions where there are little or no environmental rules and then import these products back to western countries. I believe that we need a Carbon Footprint Tax on goods imported from polluting countries and that this tax be dedicated solely to reducing national carbon footprints eg. Converting coal fired generating plants to gas etc. Not sure how feasible this concept would be but it would be a way to entice polluting countries to clean up their own environmental practices. As we are having our federal elections this month in Canada I will be visiting each candidate in my riding to suggest this idea.

what does getting politically active have to do with my carbon footprint ?

Going politically active doesn’t necessarily lower your carbon footprint, it can force the entire country’s carbon footprint down, and as a result, yours. For example, if you voted for a law to shut down a coal powered power plant and replace it with a solar or wind farm, you would be cutting down on an entire organization’s carbon footprint, and not just your own.

I do my part and after reading this article, I feel my husband and I definitely exceed these points. We hardly go out, so therefore we are not driving, we shower twice a week, we wash clothes on cold, (we don’t have that many loads because we don’t go out so therefore it’s basically pjs and underwear we are washing, we haven’t travelled in 18 years, we hardly eat meat, (we don’t eat much as it is), we do not buy clothing and use the clothes we have whether they are worn out or not, where we live, (Hudson Valley, no one cares what you look like), so therefore we are not getting rid of 80 tons of clothes a year. We sit in the dark at night, we hardly watch tv, we don’t use our computers. I’m 53 and he’s 69. We basically stopped living. However, what are your thoughts on pellet stoves to heat the home? We live in a trailer.

Thank you so much i needed this ◕‿◕

This is a helpful article and thank you. I am curious, at the institutional level, what are top tier schools like Columbia doing to demonstrate their commitment to going green? Limiting staff air travel, requiring alternating in office and WFH staff schedules, etc. These institutions are leading the charge in thought, which is incredibly important, but are they also implementing these ideas more broadly?

Hi Kella, thanks for your interest! You can read an overview of Columbia’s sustainability initiatives here: https://sustainable.columbia.edu/

Good Information on carbon footprints reduction. Actually everybody is nowadays aware that how to reduce the carbon footprints, but the question is? are we really honest in following the same? Lets commit that we will do atleast our part and if everyone will do his part… than the mother earth will be green and healthy!

I disagree with the suggestion to buy a laptop over a desktop, a laptop has a much lower life cycle and is not easily upgradable. If you got a desktop instead, while you might use more electricity, it is better due to avoiding more computer parts being thrown away. Desktops being upgradeable means you can swap parts that need to be upgraded instead of buying a whole new system everytime it becomes unusable. For example a monitor does not become unusable at the same rate as a CPU, but by getting a laptop you end up getting a new monitor everytime you get a new system despite the older one being perfectly fine.

Thanks for sharing! Avoiding flying is hard. But the pandemic has had a huge impact on air travel and we are seeing more and more of our clients (honeymooners) take road trips. Hopefully this has helped reduce their carbon footprint.

If u become vegan u will have a lower carbon footprint

Agree…. but we also have to stop burning fossil fuels, deforestation, and cement production. If we can do this, only then carbon footprint can be reduced.

No, I love my burgers, hot dogs, chicken, and pork.

Stop shopping at Trader Joe’s. Most of their packaged goods are made in Turkey, China, Vietnam, Bulgaria, etc. Orange carrot juice made in Turkey in glass bottles shipped to your local TJ’s and sold for 2.99 is a carbon disaster. TJ’s is mostly frozen dinners, highly packaged and processed foods, many with artificial flavoring and colors, high sodium and sugar and non-local produce wrapped individually in plastic and stryofoam. Walmart has better governance and transparency. Avoid Trader Joe’s at all costs.

thank you for helpimg me on a assinment i am going to make the world a better place

growing your own food and owning a few chickens is a really good way to help I think. Usually eggs from commercial farms are mass produced and are less quality.

Don’t buy toys that require batteries.

but what if I want to

Don’t go to or support: car races, hot air balloons, boats with motors, joy flights, cruise ships, jet skis etc.

Live healthfully. Healthy living & preventative care saves lots of resources.

This means cultivating a healthy body. Keeping a healthy mind

The healthcare system is full of high consumption (huge industry sector, single use everything, high energy resources.). I’m grateful resources exist but it’s best to consciously live the best you can in hopes of needing it as little as possible.

Animal feed is now being used that produces less methane in cows.

Btw, if you get breast cancer, the first thing you are told is do NOT eat soy. Many products include soy; oils labeled ‘vegetable oil’ are often 100% soy.

Also, not kidding: we tried plant based ‘fake meat’ and we had indigestion and gas for days.

Let’s go with Gore’s plan – less people. Not sure how he plans to achieve that.

Al gore has done really well with this ‘carbon offset’ business. He went from being worth $2 mil to hundreds of millions. His house in Nashville uses huge amounts of energy.

oh shoot guys this is a major problem. we have to….. CHANGE it’s so nice people care about this subject, soon all we’re gonna here about is this.

i think everyone should start to be more observant and have more respect for the things and people that put this world into shape. I also think pollution is one of the main problems and some people can fix that but chose not too and it has damaged our world.

no one Ever Looks at a Shark and Tells Him That he is Destroying the Environment By Eating Other Fish. So Why do People Look At Meat Eaters and Say we Destroy The Environment?

If there were 8 billion sharks there would be no fish.

I am beginning my journey to reduce my carbon footpring

I agree with all these things, but the 8.7 tons per capita is misleading for china as china has ~1.3 billion people inside their nation while America only has ~350 million, If you don’t know per capita is basically per person. So while china may have a lower per capita they have 3 times more people. if china had the same amount of people as the united states it would equate to ~32.3 tons per capita, giving them a much higher per capita than the U.S.

To say myself, I think this will help our planet during COVID and to increase the population of endangered creatures.

Great information. Thanks.

I’m in the midst of reading the article right now. SO GLAD TO HAVE FOUND U!!! I only recently heard on NPR that residential homes emit more carbon than I ever knew about and am madly trying to learn of all of the ways that we can contribute for the good of the climate. Am very excited to hear this news. Thank you all so much for being there and for the work that you all are doing!

Love this article!

#savetheworld

Yes save the world please our world needs help! *^*

Every aspect of everyone’s life needs to change.

Everyone must go vegan.

You can’t say everyone “Must” go vegan. It is healthy to eat meat and other stuff, not everyone can be vegan it can make people sick if they were raised eating meat. Same with vegetables if someone who was raised eating vegetables then meat may make them sick. All though neither meat or vegetable community is wrong. Though I find it rude for you to say “Everyone must go vegan” I do support you for being vegan 🙂

I think some of yall are all missing the point of the article.

? What do all our congressmen and Senators drive??

Simple and applicable suggestions – Fantastic article, thank you

Get the Columbia Climate School Newsletter →

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

• View all journals
• Explore content
• About the journal
• Publish with us
• Sign up for alerts
• Correspondence
• Published: 14 April 2023

The carbon footprint of research papers

• Riccardo Mincigrucci   ORCID: orcid.org/0000-0001-6343-6256 1  

Nature Photonics volume  17 ,  page 375 ( 2023 ) Cite this article

1151 Accesses

1 Citations

3 Altmetric

Metrics details

• Free-electron lasers
• Techniques and instrumentation

Science has a cost. While staff, equipment and consumables are standard entries in any project budget, an interesting question not explored in detail is how much energy is used to generate a research paper, and thus what is its carbon footprint 1 ?

In this specific estimate, the dominant contribution was the energy required to acquire the data while the analysis was performed using a standard computer. However, it often happens that computer clusters or supercomputers are used, with a substantial increase in the energy cost. Travels associated with the research can have a large impact as well. Often collaborators cover large distances to reach a facility or a laboratory to accomplish their research. The Airbus 380, one of the most efficient long-range airplanes, consumes about 133 kWh per hour and per person 4 , 5 . A team of five persons, crossing the ocean back and forth to attend an experiment, can have a substantial impact on the energetic budget of an eventual paper.

This is a preview of subscription content, access via your institution

Access options

Access Nature and 54 other Nature Portfolio journals

Get Nature+, our best-value online-access subscription

24,99 € / 30 days

cancel any time

Subscribe to this journal

Receive 12 print issues and online access

195,33 € per year

only 16,28 € per issue

Rent or buy this article

Prices vary by article type

Prices may be subject to local taxes which are calculated during checkout

Greenhouse Gases — Carbon Footprint of Products — Requirements and Guidelines for Quantification ISO 14067:2018 (ISO, 2018); https://www.iso.org/standard/71206.html

Mincigrucci, R. et al. Nat. Commun. 14 , 386 (2023).

Article   ADS   Google Scholar  

Thorve, S. et al. Sci. Data 10 , 76 (2023).

Article   Google Scholar  

Homer, T. How much fuel does an international plane use for a trip? HowStuffWorks (15 December 2022); https://science.howstuffworks.com/transport/flight/modern/question192.htm

Edwards, T. Reference Jet Fuels for Combustion Testing (American Institute of Aeronautics and Astronautics, 2017); https://www.caafi.org/news/pdf/Edwards_AIAA-2017-0146_Reference_Jet_Fuels.pdf

Mariette, J. et al. Environ. Res. Infrastruct. Sustain. 2 , 035008 (2022).

Knödlseder, J. et al. Nat. Astron. 6 , 503–513 (2022).

Download references

Author information

Authors and affiliations.

Elettra Sincrotrone Trieste SCpA, Trieste, Italy

Riccardo Mincigrucci

You can also search for this author in PubMed   Google Scholar

Corresponding author

Correspondence to Riccardo Mincigrucci .

Ethics declarations

Competing interests.

The author declares no competing interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article.

Mincigrucci, R. The carbon footprint of research papers. Nat. Photon. 17 , 375 (2023). https://doi.org/10.1038/s41566-023-01202-3

Download citation

Published : 14 April 2023

Issue Date : May 2023

DOI : https://doi.org/10.1038/s41566-023-01202-3

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

Quick links

• Explore articles by subject
• Guide to authors
• Editorial policies

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.