Tackling global climate change and tracking greenhouse gas emissions has become an all-hands-on-deck endeavor. The World Bank recently launched an initiative, in collaboration with NASA and the European Space Agency, to collect and organize satellite-based measurements of concentrations of greenhouse gases in the atmosphere.¹

Back on Earth’s surface, companies around the world are also tracking greenhouse gas emissions—the ones produced by their businesses and value chains. Some are using software tools to gauge their progress in achieving reductions in carbon emissions to meet ESG goals and adhere with environmental regulations.

While the urgency surrounding climate change mitigation is greater than ever, the understanding and awareness that inspired such urgency took some two centuries to develop. Let’s take a look at how climate change evolved from a little-known concept to a widely accepted phenomenon prompting action around the globe.

1800’s: Early climate science

Theories on climate change date back to the early 19th century. An early observation of what eventually became known as the greenhouse effect came from French mathematician and physicist Joseph Fourier. In 1824, Fourier wrote that gases in Earth’s atmosphere trapped heat, making the planet warmer than it otherwise would be.

In 1856, through experiments with various gas combinations, amateur American scientist Eunice Newton Foote identified water vapor and carbon dioxide—then called carbonic acid—as the heat-trapping culprits, writing that “[a]n atmosphere of that gas would give our [E]arth a high temperature.”²

Ironically, it was curiosity about ice ages rather than global warming that prompted further advancements in the understanding of modern climate change. Irish physicist John Tyndall set out to determine whether Earth’s changing atmospheric composition contributed to prehistoric ice ages. Like Foote, Tyndall experimented with different gases. In the 1860s, he demonstrated that the gas produced from heating coal—which consisted of carbon dioxide, methane and volatile hydrocarbons —absorbed large amounts of energy.³

Building on Tyndall’s findings, in 1896 Swedish physicist Svante Arrhenius developed a climate model showing how different concentrations of atmospheric carbon dioxide could impact global temperatures. Like Tyndall, Arrhenius started out theorizing what conditions might have led to Earth’s ice ages, including emissions from volcanic eruptions. Arrhenius also considered the modern sources of emissions of his era—the burning of fossil fuels during the Second Industrial Revolution—and the increases in average temperatures that they could cause.

Arrhenius predicted that it would take 3,000 years for atmospheric CO2 levels to double, leading to an increase of 5 to 6 degrees Celsius. In contrast to today’s attitudes, however, Arrhenius wasn’t leery of such potential changes to Earth’s climate. Rather, he predicted that as the average temperature rises, people will “live under a warmer sky and in a less harsh environment than we were granted.”⁴

1900s: Attitudes shift toward climate change

In the 1930s, English steam engineer and amateur scientist Guy Callendar gathered and analyzed historical temperature information and carbon dioxide measurements from around the world, finding that there had been a 0.3 degrees Celsius rise in surface temperatures and a 6% increase in atmospheric carbon dioxide between 1880 and 1935. To link the two trends, Callendar improved on Arrhenius’s equations and performed his own calculations. Ultimately, he concluded that changing levels of carbon dioxide, caused by fossil fuel combustion, accounted for half of the increase in Earth’s temperature between 1880 and 1935.

But, like Arrhenius, Callendar’s outlook on the changing climate was rosy: He predicted increased crop production in the northern hemisphere and the prevention of future ice ages.[4] By the 1950s, however, some scientists were adopting a distinctly different tone. At a presentation before the American Geophysical Union in 1953, physicist Gilbert Plass made headlines when he warned that anthropogenic carbon dioxide emissions were raising Earth’s surface temperature at a rate of 1.5 degrees per century.⁵

Later that decade, American oceanographer and climate scientist Roger Revelle showed that the oceans—considered to have a moderating effect on the amount of greenhouse gas in the atmosphere—were absorbing gas far slower than previously thought. Revelle’s colleague, Charles David Keeling, built a carbon dioxide monitoring station in Hawaii. His measurements on the Mauna Loa volcano led to the eponymous Keeling curve, a long-term data series showing increasing carbon dioxide levels that was later praised for setting “the stage for today’s profound concerns about climate change.”⁶

Late 20th century and beyond: Technology-propelled discoveries

The 1950s and ‘60s ushered in an era in which computer models became a pivotal tool for climate scientists. One of the most influential was the model created by researchers Syukuro Manabe and Richard Wetherald at the Geophysical Fluid Dynamics Laboratory, part of the National Oceanic and Atmospheric Administration (NOAA.) In a 1967 paper documenting their model’s results, Manabe and Wetherald concluded that if atmospheric CO2 doubled from existing levels, such an increase would result in a global temperature increase of 2.3 degrees Celsius.⁷ Their prediction, made in digital computing’s early days, proved surprisingly close to later findings delivered by more advanced models.

In 1969, the technology used to study climate change advanced on an additional front, with the launch of NASA’s Nimbus III satellite. Equipment on the weather satellite provided unprecedented temperature measurements for different parts of the atmosphere, giving scientists a more holistic picture of the planet’s temperature changes. Today, satellites continue to be a critical tool for gathering climate change data; recently, NASA began a collaboration with IBM to use artificial intelligence (AI) technology to extract insights from satellite data.

While scientists continue to analyze data captured from space, others take advantage of the information available below ground. Since the 1960s, paleoclimatologists have studied the composition of ice cores—cylinders of ice drilled from ice sheets and glaciers in places like Antarctica and Greenland. Deep ice cores include particles such as aerosols as well as air bubbles captured thousands of years ago, providing historic information about the planet’s climate system. Evidence yielded by Antarctic ice core research indicates that carbon dioxide ranged from 180 to 300 parts per million (ppm) during an 800,000-year timescale, markedly lower than CO2 concentrations measured today, adding further credence to concerns that the planet is experiencing unprecedented conditions.⁸

Climate science impacts global public policy

Mounting evidence about the significance and severity of climate change spurred significant global efforts on policymaking beginning in the late 1980s.

1987: The Montreal Protocol mandated that countries around the world phase out the use of substances found to deplete the ozone layer of the Earth’s atmosphere.

1988: The United Nations established the Intergovernmental Panel on Climate Change (IPCC) to advance scientific knowledge about climate change caused by human activities.

1997: The Kyoto Protocol became the first international treaty to set legally binding targets for developed countries to cut greenhouse gas emissions.

2015: The Paris Agreement brought developing nations into the fold, with emissions targets for nearly 200 signatories. The new agreement aimed to prevent the global average temperature from rising more than 2 degrees Celsius above preindustrial levels. In the same year, the United Nations adopted 17 Sustainable Development Goals (SDGs), which included emphasis on adopting sustainable energy systems, sustainable forest management and lowering emissions.

Climate change today: Urgent action through policy and innovation

In its sixth assessment report, issued in 2023, the IPCC predicted that significant and timely mitigation and adaptation efforts would reduce the adverse impacts of climate change on humans and ecosystems. The panel noted that since its fifth assessment report, issued in 2014, policies and laws on climate change mitigation have expanded.

Ongoing mitigation efforts, however, have not forestalled tangible signs of climate change, including changing weather patterns and extreme weather events. In recent years, an increase in droughts, heat waves, wildfires and intense precipitation have been attributed to climate change, as have sea level rises and declines in Arctic sea ice. Copernicus, Europe’s climate monitoring agency, declared 2023 to be the warmest year on record.

The alarming trends are prompting government and corporate leaders from Washington D.C. to Sydney, Australia to redouble their efforts to reduce greenhouse gas emissions and fight climate change. Such efforts include improving energy efficiency, transitioning to renewable energy sources and making decisions informed by ESG data-monitoring and analysis tools.

“The end game has to be net zero or carbon neutral outcomes,” said Steve Ford, Head of Sustainability at Australia-based GPT Group, a diversified property group that is reducing its carbon footprint with the help of monitoring and analysis technology. “Anyone who doesn’t see that as the end game for energy- and climate-related environment impact is playing on the wrong planet.”

As more companies focus on emissions reductions, data management is taking center stage to ensure sustainability efforts stay on track. ESG reporting software from IBM Envizi™ integrates a suite of modules that help you capture and manage all your ESG data in a single system of record and report with confidence knowing that your data is auditable and finance-grade.

¹”How is satellite data revolutionizing the way we track greenhouse gas emissions around the world?” (link resides outside ibm.com). Data Blog, World Bank. Jan. 25, 2024.

²”How 19^th Century Scientists Predicted Global Warming.” (link resides outside ibm.com). JSTOR Daily. Dec. 17, 2019.

³”Climate Change History.” (link resides outside ibm.com). History.com. June 9, 2023.

⁴“CO₂, the greenhouse effect and global warming: from the pioneering work of Arrhenius and Callendar to today’s Earth System Models.” (link resides outside ibm.com). Endeavour, Vol. 40, Issue 3, Sept. 2016.

⁵”The scientist who raised dangers of carbon dioxide in 1950s.” (link resides outside ibm.com). The Guardian. June 22, 2023.

⁶“Obituary notice: Climate science pioneer: Charles David Keeling.” (link resides outside ibm.com). Scripps Institution of Oceanography, June 21, 2005.

⁷“Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity.” (link resides outside ibm.com). Journal of Atmospheric Sciences, Vol. 24, No. 3.  May, 1967.

⁸“What do ice cores reveal about the past?” (link resides outside ibm.com). National Snow and Ice Data Center, CIRES of at the University of Colorado Boulder. March 24, 2023.