The Keeling Curve, Fossil Fuel Deception, and Climate Change Lawsuits

Article by Milberg Senior Counsel and environmental lawyer Melissa Sims

In the 1950s, the American Petroleum Institute (API), the leading U.S. lobbying body of the oil and gas industry, inadvertently catalyzed a pivotal scientific endeavor that would help to expose the role of the greenhouse effect on climate change.

Spearheaded by Charles David Keeling, the Keeling Experiment, initially backed by the API, illuminated the insidious rise of carbon dioxide levels in the atmosphere. Yet as his research exposed the undeniable link between human activity and climate change, the fossil fuel industry embarked on a deceptive campaign to obscure the truth he uncovered.

Decades later, the API’s sponsorship of Keeling’s research has reemerged as evidence that the same fossil fuel interests that have fought to undermine climate science knew all along about the potential dangers of their products.

Charles Keeling and the Keeling Curve

In the late 1950s, when concerns about the impact of carbon dioxide (CO2) emissions on the Earth’s climate were still in their infancy, Charles David Keeling, a young scientist from Caltech, embarked on a groundbreaking endeavor to monitor atmospheric CO2 levels. Keeling’s pioneering work laid the foundation for what would become one of the most critical tools in climate research.

In a surprising and ironic twist, newly discovered documents show how the collaboration of the oil and gas industry played a crucial role in the development of Keeling’s project. As the Guardian reports, a coalition of fossil fuel and car manufacturing companies financed a group called the Air Pollution Foundation that provided funding to Keeling’s CO2 measuring project.

Founded in 1953, the Air Pollution Foundation was formed to address the infamous smog of Los Angeles. At the time, oil and auto companies were primarily concerned with understanding how combustion processes, such as those involved in fossil fuel extraction and consumption, contributed to atmospheric pollution. Keeling’s measurements of atmospheric CO2 were seen as a way to better understand these processes and their environmental impacts.

The industry was not just on notice but deeply aware of the potential climate implications of its products for going on 70 years.

With the backing of the Air Pollution Foundation, Keeling established a research station at Mauna Loa Observatory in Hawaii, far from industrial pollution sources, where he could collect pristine air samples. The site’s remote location and consistent airflow provided an ideal setting for monitoring atmospheric CO2 levels.

At the heart of the Keeling Experiment was the meticulous measurement of atmospheric carbon dioxide concentrations. Keeling’s data charted the steady ascent in CO2 levels, forming the now iconic Keeling Curve. This empirical evidence laid bare the greenhouse effect, demonstrating how human activities, particularly the burning of fossil fuels, trap heat in the atmosphere and drive global warming.

Keeling’s measurements showed that, year by year, CO2 levels were steadily rising. His seminal work has only taken on greater importance as atmospheric CO2 continues to rise. Today, carbon dioxide levels are higher than at any point in human history. Scientists have confirmed that 2023 was the planet’s hottest year on record by a significant margin.

Industry Goes on the Offensive Against Science They Backed

Although it funded Keeling’s work, the fossil fuel industry soon found itself at odds with the inconvenient truths emerging from his research. As evidence of the greenhouse effect mounted, vested interests within the industry, including companies like Shell and Exxon, sought to undermine the scientific consensus and perpetuate doubt.

Carroll Muffett of the Center for International and Environmental Law told the Guardian that the recently unearthed documents add to evidence that “The industry was not just on notice but deeply aware of the potential climate implications of its products for going on 70 years.”

Through well-financed lobbying endeavors, strategic disinformation campaigns, and the amplification of dissenting voices within the scientific community, the fossil fuel industry attempted to discredit the reality of the greenhouse effect. By framing climate change as a contentious debate rather than an established scientific fact, they aimed to protect their profits and delay regulatory action.

However, while publicly sowing seeds of doubt, internal documents from major fossil fuel companies paint a starkly different picture. These documents, brought to light in subsequent investigations, reveal a troubling truth: industry executives were acutely aware of the risks posed by the greenhouse effect as early as the 1970s. Despite this awareness, they chose profit over planetary well-being, perpetuating a dangerous cycle of denial and delay.

One such example is Exxon’s own predictions in 1978, which aligned closely with the findings of the Keeling Experiment. Internal documents from Exxon forecasted how much the planet would warm due to increased carbon dioxide emissions, demonstrating a clear understanding of the consequences of their operations.

Litigation Questions What Industry Knew—And When They Knew It

The revelations that fossil fuel companies knew about the impact of CO2 emissions for decades have laid the groundwork for a wave of accountability lawsuits against them.

Leveraging the Keeling data and other scientific evidence, communities, activists, and governments are filing lawsuits that take fossil fuel companies to task for perpetuating climate change and its attendant harms. These lawsuits seek to recover damages for the impacts of climate change, including sea-level rise, extreme weather events, and loss of biodiversity.

Milberg’s first-of-its-kind climate change lawsuit on behalf of Puerto Rican municipalities, based on RICO conspiracy, references the work of Charles Keeling, noting that atmospheric CO2 concentration was 313 ppm at the time of Keeling’s first measurement from Mauna Loa. Currently, that number is 422 parts per million—nearly one-third higher than in 1958 and 50% higher than during the pre-industrial era.

Ms. Sims was recognized in the Time 100 Climate List 2023 for her creative and pioneering legal strategies in the Puerto Rico climate change case against fossil fuel companies for hurricane-related losses.