The Infuriating Story Told by the Corporate and National Carbon Emissions Data

March 18, 2025 | 9:30 am
Sean Gallup/Getty Images
Carly Phillips
Research Scientist

Accountability for past emissions should be a critical part in addressing climate change. But the first step in seeking accountability for the highest emitters, whether corporations or countries, is quantifying their contributions. While the pursuit of accountability should consider their role in creating and spreading disinformation and their deception around climate science and research, their contributions of heat-trapping gases to the atmosphere are an important place to start. Here, I’ll describe the data currently available to quantify these emissions, what they tell us about the drivers of climate change, and how we can achieve accountability for its harms moving forward.  

Who are the Carbon Majors?  

The Carbon Majors are the largest fossil fuel producers and cement manufacturers, and a group to which 67.5% of all fossil fuel and cement emissions can be traced. To put a finer point on the immense impact of just a few organizations, more than one-third of these industrial emissions can be traced to just 26 companies. The Carbon Majors database includes emissions traced to investor-owned companies like ExxonMobil, BP, and Peabody; state-owned entities like SaudiAramco and Gazprom; and a handful of nation-states with dedicated fossil fuel and cement production, presently or historically, like China, Former Soviet Union.  

Earlier today, my colleague Shaina Sadai released a peer-reviewed study that links emissions traced to the Carbon Majors to present-day and future sea level rise. This study adds yet another example of how emissions from these entities are driving climate impacts globally. Previous UCS studies have already linked their emissions to increases in global average temperature, ocean acidification, and area burned by wildfires. When considered with the growing evidence of companies’ deception and disinformation, these studies paint a damning picture of how these companies shaped our world and the inequities that they’ve reinforced globally.  

These data also show that although humans have been emitting heat-trapping emissions into the atmosphere since the industrial revolution, 50% of emissions traced to the Carbon Majors have been released since just 2000.  When visualizing data, clarifying the units used is critical. When it comes to emissions, this means distinguishing between cumulative historical (all the heat-trapping emissions they’ve ever emitted over time) and annual (all emissions each year). Both aggregations tell important stories that can help us to mitigate and adapt to climate change, but not specifying how the data are expressed is not only imprecise but can be deliberately misleading.  The data in the figure below show annual emissions measured in gigatons of CO2 per year.  

Source: UCS/Carbon Majors Dataset

As I wrote in an earlier blog that detailed the nitty gritty and backstory of this data, lawsuits and legal submissions worldwide cite the Carbon Majors Dataset to draw attention to the outsized role of fossil fuel companies in driving the climate crisis, including:  

  • Lliuya vs RWE, where a Peruvian farmer is suing one of Europe’s largest emitters of heat trapping gases for its role in increasing the risk of a glacial lake outburst flooding, which threatens him and the entire community of Huaraz. This case uses the Carbon Majors Dataset to quantify RWE’s contribution to global historic emissions.  
  • Greenpeace Italia vs ENI, where affected communities are suing to force ENI, Italy’s largest energy company, to reduce emissions and limit global warming. This case uses the Carbon Majors Dataset and source attribution research to underscore the outsized role of ENI in driving climate change. 
  • People of California vs Big Oil, where California is suing ExxonMobil, Chevron, BP, Shell and others for misleading advertising, failure to warn and fraudulent business practices. This filing uses these data to demonstrate that the contribution of heat-trapping gases traced to their defendants is quantifiable.  
  • Multnomah County vs Big Oil, where the largest county in Oregon, home to Portland, is suing ExxonMobil and others for damages and adaptation costs following 2021’s unprecedented and deadly heatwave. This filing uses the Carbon Majors Dataset to show that emissions attributable to each entity are calculable using the amount, type, and emissions factor associated with each product.   
  • InterAmerican Court of Human Rights, where Colombia and Chile requested an advisory opinion to clarify the state’s human rights obligations in light of climate change. UCS’ joint intervention used these data to highlight the role of a handful of corporations play in driving climate change.  

What about emissions from countries?  

When it comes to emissions, fossil fuel companies are not the only entities that have disproportionately contributed to the atmosphere’s ever increasing concentration of heat-trapping emissions. Some countries, like the United States, Russia, China and Germany, have also contributed an outsized amount of emissions to the atmosphere, and as a result should bear a proportionate amount of responsibility for addressing climate change and its impacts.   

The data presented below are from the Global Carbon Project and separate from the Carbon Majors data discussed above. This figure displays annual emissions by country, highlighting the massive historical contribution of the United States (nearly 25% of total global emissions), where several large Carbon Majors are headquartered. But more discouraging are the barely visible contributions (shown in purple) of many nations that are now bearing the brunt of climate change impacts —countries like Tonga and Pakistan, among many, many others. Plotted together, these data tell a powerful story about historical contributions and contextualize discussions around future responsibilities.  

Source: Global Carbon Project 

What do these data mean for climate accountability?  

Emissions attributed to both the Carbon Majors and individual countries paint a picture of historical contributions that’s difficult to unsee—and inspires a call for accountability.  

In the US, states, counties, and communities are seeking accountability through the courts. These lawsuits primarily focus on fossil fuel companies’ deception and disinformation campaigns that delayed climate action for years and continues to pollute our public discourse.  While industry, trade groups, and their political allies have fought to dismiss the suits, courts across the country, including the Supreme Court just last week, have continued to affirm the right to seek accountability through the courts.  

Internationally, high emitting countries continue to benefit from their historical emissions at the expense of many emerging economies that bear the brunt of climate impacts but have contributed the least amount of heat-trapping emissions. In multilateral agreements, powerful countries have resisted and slowed the adoption of mechanisms for accountability sought by more vulnerable nations.    

At COP27 of the United Nations Framework Convention on Climate Change, countries around the world established a Loss and Damage Fund to aid developing countries who are most vulnerable to climate change but have contributed the least to the atmosphere. Countries initially pledged more than 700 million dollars to the fund. While this appears to be an entry point in the path toward accountability, this amount is far below the estimated need of 300 billion annually by 2035 – just 0.2% of what is needed  Further, in early March, the US announced its withdrawal from the Loss and Damage Fund.  

But these data don’t tell the full story, particularly regarding the environmental racism and injustice wrought by the fossil fuel and high-emitting countries. This is especially evident in Cancer Alley in southern Louisiana, where a high density of petrochemical plants and refineries with scarce regulation and willful neglect, have led to elevated rates of cancer and other health issues, a burden particularly borne by Black residents.  

The Trump Administration has already reneged on the US’ bare minimum commitments  to address issues of climate justice. We’ve seen fossil fuel industry leaders and climate deniers put in positions of authority. The US has pulled out of the Paris Agreement and stopped federal scientists from engaging with the Intergovernmental Panel on Climate Change, a global scientific body.  

These data—both for countries and major carbon producers—tell a clear story about the history of human climate pollution, and the responsibilities of large emitters to act as the impacts of climate change grow increasingly severe. The need to hold them accountable, and guarantee they take up that responsibility, must guide our work every day.