Tracing Who’s Responsible for Temperature Increase and Sea Level Rise

Rachel Licker, Brenda Ekwurzel, Peter Frumhoff

Published Aug 17, 2017 Updated Mar 5, 2020


Updated based on new evidence of when fossil fuel companies and their industry associations knew that their products caused harm. Also updates fact sheet.

The impacts of global warming are here and they are costly. Sea level rise floods towns and erodes shorelines. Frequent and intense heatwaves threaten our workers’ health and damage our infrastructure. Extreme weather ruins our crops and corrodes businesses, factories and homes. In New York City alone, officials estimate that it will cost $19.5 billion dollars to prepare the city for sea level rise. And globally, climate adaptation costs are staggering.

Will top fossil fuel producers help shoulder the costs? They should.

As early as 1965, investor-owned fossil fuel companies knew their business was risky—that the use of their products released dangerous amounts of carbon dioxide and methane emissions that could destabilize our climate.

These companies could have taken steps to reduce the risks. Instead, they chose to misinform the public and their investors, block action to limit carbon emissions and carried on with business as usual.

But, we now have the science to determine how much the emissions related to fossil products have contributed to global temperature rise and sea level rise.

A peer-reviewed study, authored by Brenda Ekwurzel, James Boneham, Mike Dalton, Rick Heede, Roberto Mera, Myles Allen and Peter Frumhoff and published in Climatic Change, analyzed and quantified the climate change impacts of carbon dioxide and methane emissions traced to each company for two time-periods: 1880 to 2010 and 1980 to 2010.


Emissions traced to the largest 90 carbon producers contributed:

  • 57% of the observed rise in atmospheric carbon dioxide since 1880
  • Nearly 50% of the rise in global average temperature since 1880
  • About 30% of global sea level rise relative to 1880 levels

Emissions traced to 50 investor-owned carbon producers, including BP, Chevron, ConocoPhillips, ExxonMobil, Peabody, Shell and Total, were responsible for:

  • Roughly 16 percent of the global average temperature increase from 1880 to 2010,
  • And around 11 percent of the global sea level rise during the same time frame.

Emissions traced to the same 50 companies from 1980 to 2010, a time when fossil fuel companies were aware their products were causing global warming, contributed:

  • Approximately 10 percent of the global average temperature increase
  • And about 4 percent sea level rise since 1980.

Building a case for responsibility

The study builds on landmark research published in 2014 by Richard Heede, of the Climate Accountability Institute. Heede’s initial research quantified the carbon dioxide and methane emissions resulting from burning the products of the 90 largest carbon producers.

Ekwurzel and her co-authors used Heede’s data on company emissions in a climate model that captures how these emissions are incorporated into the Earth’s carbon cycle.

The study used emissions data on the 90 carbon producers in a simple, well-established climate model that captures how carbon dioxide and methane emitted into the Earth’s atmosphere lead to the trapping of heat and drive increases in global surface temperature and sea level. Using this model, they were able to quantify the results of including or excluding different natural and human contributions to climate change—including the very specific contributions of emissions attributed to these companies’ products.


Licker, Rachel, Brenda Ekwurzel, Jean Sideris, Peter Frumhoff. 2020. Tracing Who’s Responsible for Temperature Increase and Sea Level Rise. Cambridge, MA: Union of Concerned Scientists.

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