MIT Climate Clock


MIT Climate Clock

"The 2018 Intergovernmental Panel on Climate Change Report starkly presented the challenge society faces to achieve rapid progress on cutting emissions in this decade:
Without increased and urgent mitigation ambition in the coming years, leading to a sharp decline in greenhouse gas emissions by 2030, global warming will surpass 1.5°C in the following decades...
We need to come together now, both within MIT and with like-minded people and institutions everywhere, if our common effort is to succeed."
Students viewing the MIT Climate Clock on top of South Face of MIT’s Green Building, Earth Day (4/22/2022)


"If we act swiftly, it is not too late to prevent much more severe changes to the Earth's climate." - MIT Climate Portal

The Climate Clock is the effort of a diverse group of students, faculty and alumni who seek to share the urgency of the climate crisis with the wider community in order to raise awareness and spark action. As members of the younger generations, who will experience the impacts of decisions made by those in power today, we feel it is imperative to make our voices heard.

Currently, there is no everyday measure that informs us about the health of our planet. The MIT Climate Clock presents to the MIT community and to the wider world essential information about the climate emergency that is here now. The purpose of the Climate Clock is not to frighten or politicize, but to raise awareness of troubling scientific measures and to motivate people to come together to plan for our collective health and safety. Our role is to be one warning beacon among many.

World Scientists Warning of a Climate Emergency

Scientists from around the world warn us that we are in the midst of a climate emergency. In their "World Scientists Warning of a Climate Emergency," over 14,000 scientists from 158 countries present graphical data showing vital metrics about our climate. They write that, "greenhouse gas emissions are still rising, with increasingly damaging effects," and that, "with few exceptions, we are largely failing to address this predicament."

This warning draws on a long history of scientists raising alarms about the state of our earth. In 1992, MIT professor and Nobel Prize winner Henry Kendall spearheaded the "World Scientists Warning to Humanity 1992," which argued for the need to curb environmental degradation, lest we "so alter the living world that it will be unable to sustain life in the manner that we know."

In parallel to scientists' warnings, over 1,900 local governments in 34 countries have now formally declared a climate emergency. These efforts are essential and reinforce our obligation as citizens of the world to seek to protect the earth before it is too late. It is in this spirit that we undertook the climate clock project.

The Idea

What the Climate Clock Shows

We project scientifically accurate information on the top of the south face of the Green Building. The building is both the tallest building in Cambridge, and home to the MIT Department of Earth, Atmosphere and Planetary Sciences. The MIT Climate Clock features four lines that highlight the need for climate action.



to limit global temperature increase to 1.5°C (2.7°F) which is the target embraced in the COP21 Paris Agreement. The Paris Agreement, signed in 2015, is a legally binding international treaty on climate change to "limit global warming to well below 2, preferably to 1.5 degrees Celsius, compared to pre-industrial levels"

Carbon Dioxide Emissions Budget

a very large number from which one derives the actual time of the climate clock. The "Carbon Dioxide Emissions Budget" represents how much carbon dioxide the world as a whole can release into the atmosphere with at least a 66% chance of avoiding global average temperature increases of 1.5°C (2.7°F).


Credible current projections suggest we have about seven years left at current emission rates. The "Deadline" is another way of expressing the carbon dioxide emissions budget. It's the time we have left to take decisive action to limit global average temperature increase to 1.5°C (2.7°F).


The "Lifeline" represents the percentage of the world's energy that is currently provided through renewable sources.

The Solutions

Change for Climate!

Let's change our climate trends for the better by scaling up great solutions!

The MIT Climate Clock Team endorses Project Drawdown Solutions.

Project Drawdown Solutions across sectors to reduce sources, support sinks, and improve society

For additional inspiration and action-oriented ideas, visit the following resources:

For additional MIT Climate Solutions - stay tuned for updates!

If you have a solution you'd like to share with us, please Contact Us.

The Numbers

Where they come from

Our carbon dioxide budget data is aligned with the latest IPCC AR6 2021 report (see table SPM.2). The resulting deadline should closely mirror the numbers displayed on the Mercator Institute website . Lifeline estimates are the result of counting forward from the middle of 2020 starting from 12.55%, based on data from the World Energy 2021 Special Report.

Carbon Dioxide (CO2) Accounting Guide

In order to figure out the time available for action, one can compute a carbon dioxide budget. The budget answers the question "how much carbon dioxide can we put into the atmosphere, globally, before reaching 1.5°C above pre-industrial levels?"

To solve for the budget, one needs to know the "account limit" and the expenses.

The Account Limit: Carbon Dioxide Threshold

Using measurements and models, scientists calculated the maximum amount of carbon dioxide that can be in the atmosphere without exceeding a certain average temperature above pre-industrial levels by 2100. The number is approximately 400 giga-tonnes of carbon dioxide [IPCC AR6].

The Expenses: Atmospheric Carbon Dioxide

But how much carbon dioxide is already in the atmosphere? Measurements are taken regularly at Mauna Loa Observatory in Hawaii. At the start of 2022, there was already 417 ppm of carbon dioxide in the atmosphere, up from under 300ppm in 1950 [IPCC AR6, A.1.1]. Every year that more carbon dioxide is emitted into the atmosphere, atmospheric carbon dioxide "expenses" increase. By the same token, as we reduce our CO2 emissions, or sequester carbon, our expenses decrease. If our sequestration equals our emissions, we've hit "net-zero," such that we're removing as much carbon from the atmosphere as we're putting into it.

The Balance: CO2 Emissions Budget

The balance is simply the limit minus the carbon dioxide already in the atmosphere. We call this number the "CO2 Emissions Budget." It decreases each day as more carbon dioxide goes into the atmosphere.

For more resources describing carbon budgets, see Climate Change: What is the carbon budget? and The Carbon Budget - what is it and why is it important?

Arriving at a CO2 Budget

To convert the carbon dioxide budget into a countdown clock, we make assumptions about our world. We assume that global carbon dioxide emission rates stay fixed, and calculate how much time is left before the budget is used up. We use the assumption that the CO2 Emissions budget is reduced by 42.2 Gt of CO2 per year, or 1,337 tonnes/sec based on this reference: Mercator Research Institute on Global Commons and Climate Change (MCC). The Mercator Research Institute relies on data from the recent IPCC Special Report on Global Warming of 1.5°C . Calculations are based on the year 2020, counting down the expended carbon budget from there. The budget specifically addresses carbon dioxide, not directly including additional greenhouse gasses such as methane. Carbon dioxide is particularly important, as it remains in the atmosphere on the order of 300-1000 years.

There are other limitations to our budget calculation. The annual emissions of 42.2 Gt-CO2/yr from the MCC include sources like "burning fossil fuels, industrial processes and land-use change". They do not factor in additional emissions from long-term changes in natural sources and sinks due to potential thresholds and tipping points, such as such as permafrost melting causing the release of gas hydrates, melting of the Greenland or Antarctic ice sheets, slowing down the North Atlantic deep ice circulation or the dieback of the Amazon rainforest. While the effects of these natural sources are large, the timescale for these changes may be on the order of decades to centuries, which is much longer than the timescale of our climate clock. Thus we chose not to include these in the budget (but will continue to revisit those issues).

COVID-19 temporarily changed our global carbon dioxide emission rate. According to the Global Carbon Project report from December 11, 2020, "Total CO2 emissions from human activities (from fossil CO2 and land-use change) are set to be around 40 billion tonnes of CO2 in 2020, compared to 43 billion tonnes of CO2 in 2019." Furthermore, "global fossil CO2 emissions are expected to decline approximately 2.4 billion tonnes of CO2 in 2020 (-7%), a record drop. The decrease in emissions, caused by COVID-19 confinement measures in place, brings global fossil CO2 emissions to 34 billion tonnes of CO2... Emissions in 2019 were only 0.1% above emissions in 2018, at 36.4 billion tonnes of CO2."

Since 2020, we have begun to see a rebound effect, however. Thus we can approximate total annual emissions, mostly from fossil fuels and land use changes, as 42.2 GtCO2 for the purposes of our climate clock.

Of course there is uncertainty in our future emissions. Our goal is not to predict the future, but rather to ignite action to move towards a liveable future for humanity. Visit the Global Carbon Project to learn from scientists about how international responses to COVID-19 have impacted emissions, and thus the carbon dioxide budget.

Measuring the Progress of Renewable Energy

Energy produced from burning fossil fuels contributes more than any other source to the increasing levels of carbon dioxide in the atmosphere. Sourcing energy from renewables instead means less carbon going into the atmosphere. It was estimated in the World Energy Special Report 2021 by BP that in 2020, 12.55% of the world's energy came from renewable sources and hydro-electric: 5.7% from renewables, and 6.86% from hydro [World Energy Special 2021 Report, page 11]. Including nuclear leads to ~16.8%. Energy consumption consists of electricity, transport and heating energy. When examining just electricity, renewables (including hydro) comprise 27.8% of the electricity sources in the world [WE report, page 65]. In our accounting, renewables include solar, wind, hydropower, and modern bio-fuels. We do not include nuclear, or traditional biofuels (such as fuel-wood, forestry products, animal and agricultural waste) in the estimate. Around the world, even as the supply of energy increases, more and more energy is derived from renewable sources.

To pass net-zero, the point when globally we begin extracting carbon from the atmosphere, we need this percent to increase as much as possible towards 100%. According to World Energy data, the growth rate of renewables (and biofuels, no hydro) for 2020 was 12.5%. In fact, despite decreases in energy consumption, renewable generation still increased. For hydro it was 1% with 4296 Terra-watt-hours of energy from hydro.

For our computations, we use the following numbers:
2020 renewables (hydro+solar) = 38.16 + 31.71 = 69.87eJ
2019 renewables (hydro+solar) = 37.69 + 28.82 = 66.51eJ
2020 total energy consumption = 557.10eJ
2019 total energy consumption = 581.51eJ
2020 renewable energy / total = 12.541734%
2019 renewable energy / total = 11.43746%

For our projection, we begin at 12.541734% at the middle of 2020, and approximate the increase of renewables based on 3.501617*10^-8 %/sec, which comes from (12.541734%-11.43746%)/(365*24*3600s). If nuclear were included as a low-carbon source, the lifeline would be roughly 4.24% higher.

The Creation

The Story of the Climate Clock

The MIT Climate Clock team originated as an MIT D-Lab term project in Spring 2020, and has continued from then until now. Originally conceived of as a hack part of a long tradition of hacks-tomfooler-pranks around campus — the climate clock idea has changed over time. It was originally inspired by the CITGO sign in Boston, a prominent feature of the Boston skyline, advertising a petroleum corporation. We wanted to create a new landmark on the skyline, marking a different era with different priorities and values.

The MIT Climate Clock team ultimately opted not to do the clock as a hack, but instead to pursue MIT Administration approval, because we sought to display the climate clock in the most fitting location on campus — the top of the Department of Earth Atmospheric and Planetary Science building — and to do so long-term. Like clocks in medieval town centers, we wanted our clock to be seen every day at the center of our campus.

Building the Clock

You can share the Climate Clock too!

You can build a Climate Clock in your own home, community, school or university, even at a public park or public square. You can promote a climate clock on social media.

How many students does it take to build a climate clock? Not very many, actually (our core team is currently comprised of nine people). Here are a few resources if you want to build your own climate clock on your campus, school, at work, in your city, or on a webpage.

Possible Projection locations around the MIT Green Building

Check out our code for the numbers and clock website

The World

Climate clocks and news media abound

Climate Clocks are beginning to pop up everywhere. Here is one that first began in June 2021 in downtown Glasgow, Scotland.

Glasgow Climate Clock

Others have been displayed in locations from Union Square, in New York, to Seoul.

For more information, visit the Climate Clock website, where creators of the first climate clock have put lots of helpful information.


Read more about our project and progress

WGBH 4-22-22: MIT team's climate clock will shine over Cambridge

Boston Globe 4-24-2021: MIT Students Display Climate Clock

MIT D-Lab 4-22-2021: MIT Climate Clock from D-Lab

Climate Portal 12-16-2020: Students are building an MIT "Climate Clock"

MIT Open: MIT D-Lab Launches Climate Clock on Green Bldg 4-26-2021: MIT projects climate clock onto building

Climate Portal: Freshwater and Climate

The Future

Next Steps for the Climate Clock

From April, 2021 to the present, the MIT Administration has approved and supported the MIT Climate Clock for four short-term projections:

MIT Green Building South Face April 2021
Projection 1: April 22 (Earth Day) to April 30, 2021. The location of this projection was at the bottom of the south façade of the MIT Green Building.
MIT Green Building West face Fall 2021
Projection 2: October 29 to November 21, extended to December 21, 2021. The location of this projection was at the top of the west façade of the MIT Green Building.
MIT Green Building Top South Face April 2022
Projection 3: April 22 (Earth Day) to May 27, 2022. The location of this projection was at the top south façade of the MIT Green Building.
MIT Green Building Top South Face April 2022
Projection 4: November 8 to 18, 2022. The location of this projection was at the top south façade of the MIT Green Building.

Having now completed the 4th short-term projection of the MIT Climate Clock, we are once again requesting of the MIT Administration/MIT Climate Nucleus permission to display the MIT Climate Clock long-term.

In addition, the team has conducted a 10-question climate survey of the MIT community over a period of two weeks concurrent with COP 27. Survey results will be posted here once reviewed and approved by the Climate Nucleus.

In 2021, the team projected onto the west side of the Green building, as seen in the video below.

Video Credit: Gaurav Patekar

Beyond MIT, with our partners and team members at Harvard University, we projected the climate clock in Harvard Square on Lehman Hall for an Earth Day event on April 22nd, 2022.

As part of our parallel Earth-Day events at MIT and Harvard, we engaged people using Climate Interactive's En-ROADS simulator to learn about the climate. Plant-based ice cream served in compostable dishes was served to showcase sustainable food solutions.

En-ROADS at MIT on April 22 2022
En-ROADS and Climate Clock projections at Harvard on April 22 2022
Photo Credit: Ella Lopez

Just a handful of team members took the climate clock idea from dream to reality, and we did so during the COVID-19 pandemic!

Jillian next to the projector on the West face
Gaurav and Alejandro during assembly
Alejandro inside the projector doghouse

Photos show MIT Climate Clock team members: Jillian James (MIT'10, '16) left, and Gaurav Patekar (MIT'21) center and Alejandro Diaz (MIT'21), right.

Going forward, we will integrate feedback from the community and seek long-term approval, now that we have successfully demonstrated "proof of concept."

Climate Clock LED Backpack

Taking the clock on the road

Credit: Claire Wang

Beyond the big screen, we've gone mobile via backpack! Gaurav Patekar (MIT'21) conceived of a community awareness project where climate information is displayed on an LED backpack. People can volunteer to borrow the backpack for a week, sparking conversations about our climate. Volunteers can then pass the backpack on to another person to continue the chain of engagement.

Group showing off Climate LED backpacks
Henri and Jessica with backpacks showing 420ppm CO2 in atm. and climate deadline 7 years 3 months

Vision of Hope

"Together we can change!"

This project has given us hope. As one team member, Jenning Chen, MIT'21, puts it "I am a senior. I am graduating after four years. Yet this is the best thing I have ever done at MIT."

History has shown that with united action, we can have a global impact. It's been done before. For example, as a direct result of global actions taken after signing the historic Montreal Protocol, satellite data has shown that the ozone hole has healed.

In 2021, climate campaigners at the Glasgow, Scotland Conference of the Parties COP26 turned out in huge numbers, massively exceeding expectations. Youth-led groups, such as Friday for the Future, Extinction Rebellion and the Saturday Global Day of Action showed that the climate movement by youth and ordinary citizens matters and can make a difference.

Humans are a powerful species — we have changed the climate of the entire planet without intending to. Now, with conscious effort and the force of a committed global community, we must help create a livable climate to survive. By acting together, we can turn this emergency into an opportunity to create a better world. The ultimate goal that we aspire to is a habitable and equitable planet for all humans and all life on Earth.


The Climate Clock projections have been a sustained effort on the part of an outstanding team. The undergraduate and graduate cross-disciplinary team comes from Electrical Engineering and Computer Science, Mechanical Engineering, Aero-Astro, Chemistry, the Media Lab, as well as Harvard University Law and Medical Schools, all tied together through the D-Lab class project.

Original team members include Alejandro Diaz (MIT'21, Course 6.2), Gabriela Cazares (MIT'2020, Course 5, now in a Ph.D. at UC-Berkeley studying atmospheric chemistry) and Lowry Yankwich, Harvard Law School '22, all three of whom kicked off the pre-Climate Clock project during summer 2020.

In 2020, the team was joined by alumna Jillian James, MIT'10, '16, Course 16, who has supported all aspects of the work. Spring 2021 term added new team members Jenning Chen (MIT'21, Course 6.3) who worked with Alejandro to do all the programming, as well as Gaurav Patekar, MIT'21, Media Lab, who did major design work with Alejandro to ensure that the Climate Clock actually went live, first in Spring 2021 and then Fall/Winter 2021. Our team leaders and mentors are Susan Murcott (MIT'92), Lecturer, MIT D-Lab and Julie Simpson, Research Engineer, MIT Sea Grant.

Hear what our team has to say!

Contact Us

We would love to hear your story, and are open to collaboration!


A Sincere Thank You
Finally, we couldn't have done the MIT Climate Clock without broad community support! We acknowledge the following people and groups:
  • MIT Alumni for Climate Action (MACA) for endorsing and promoting the MIT Climate Clock
  • Jim Zaorski, MIT '80, Course 2, for financial support of the Climate Clock
  • Maria Zuber and Jim Gomes, MIT Office of the Vice President for Research
  • Joe Higgins, VP for Campus Services and Stewardship
  • Tim Jamison, Associate Provost
  • Robert van der Hilst, Head, Earth Atmospheric and Planetary Sciences
  • Ana Patelic, Director D-Lab
  • Lachlan Patterson, Sr. Project Manager, MIT Dept. of Facilities
  • Paul Murphy III, MIT Dept. of Facilities. Program Mgr., Special Projects
  • Captain Martin and many officers, MIT Campus Police
  • Brian Pretti, MIT Dept of Facilities
  • K.C. Lavery and Bob Dooley, Barr & Barr Inc.
  • David & Ta, Barr & Barr Inc. carpenters
  • Rob Shea at MIT AV
  • Michael A Smith, Sarah MacDonald-Williams, Project Manager, Sonia A Richards, Admin Asst, Capital Projects
  • Monica Lee, Senior Communications Officer, MIT Dept. of Building Construction
  • David Thorburn, Prof. Literature
  • Shankar Ramon, Section head Literature
  • Agustin Rayo, Head SHASS
  • The 14 faculty member "Climate Nucleus"
  • Lianne Martin, Campus Activities Complex
  • Nancy Adams, D-Lab Communications Officer
  • Ted Johnson and Judith Zinker, MIT Institute Events
  • Jessie Smith, Director, Open Space Programming
  • Greta Thunberg, plus Andrew Boyd and Gan Golan, the NY artists, all three of whom are the originators of the first Climate Clock