With the conclusion of COP26 in Glasgow and all the focus on National Defined Contributions, pledges to eliminate coal production and reductions in support of the petroleum industry made headlines, its worth taking a moment to take stock and remember where we stand and the foundation that has been set. An agreement between the U.S. and China and other new commitments made for a consensus of progress but not the transformative change many hoped for. What progress has been made and how did we get here?
Global CO2 emissions have been stable for the last 10 years. The big concern is that they will start to increase again.
Emissions in Europe and the U.S. have been declining for nearly 20 years. This shows its possible to decouple economic growth from emissions.
Emissions in the developing world, especially China, India and most of Asia are skyrocketing.
In sum the trend in global emissions must decrease rapidly to avoid creating a stock of CO2 in the atmosphere that will be too large and take too long to remediate.
Global concentrations of CO2 in the atmosphere continue to rise. As I write this, they have topped 420 parts per million for the first time. Only 37 percent of the world’s electric supply comes from low-carbon sources (Rhodes, 2021). The global pandemic doesn’t seem to have slowed the pace of climate change.
The cherry blossoms bloomed the earliest they have in 1,200 years in Kyoto. The weakening polar vortex slung freezing temperatures into Texas in March 2021, collapsing an electric grid that wasn’t resilient enough to handle it, causing nearly statewide power outages for a week or more. Sea temperatures and levels are rising. The year 2020 was the worst wildfire season ever recorded in the western United States, and 2021 is headed in the same direction. It’s demoralizing. You can feel the tension, the tiredness, and the burnout.
We have much work to do. It would be fair to say that almost any report out of Glasgow would not be enough. This is the nature of global consensus based diplomatic policy formation. Very seldom does it yield that singular watershed moment. Its evolution not revolution.
However, it’s worth remembering the pursuit of dogged, careful science over decades that has put us on firmer ground. One thing lacking from this COP that has existing in others is the flat denials and refusals to act. It was only a few years ago that the U.S. backed out of the Paris Accord all together. It was only a few years before that, when developing nations were refusing to act until the developed countries committed to more aid. We have come along way. Its worth giving the basic scientific foundation a reframe.
It’s the story of the methodical grind of science over more than two centuries. Like so many basic scientific discoveries, it started with European nobleman and clergy in the eighteenth and nineteenth century. It was the Enlightenment. The carbon cycle was first articulated by Antoine Lavoisier, a French nobleman, and Joseph Priestley, a clergyman and teacher. Both studied chemistry. Priestley discovered oxygen. Lavoisier discovered the law of conservation of mass. Many others followed to flesh out the details and popularize this description of how carbon flows through our environment. This is just one cornerstone of the science behind global warming and climate change.
Carbon dioxide’s heat-trapping powers weren’t understood until much later. In the 1850s, Eunice Newton Foote, a thirty-seven-year-old female American physicist, discovered a bottle of CO2 placed in the sun rose to a higher temperature than that of a bottle filled with air. Other scientists explained the physical properties that caused this effect. Svante Arrhenius was a Swedish physical chemist and Nobel laureate. Amazingly, in the 1890s (yeah, one hundred thirty years ago), he estimated if the CO2 concentration doubled, the Earth would be four degrees Celsius warmer. Directionally, this is correct. It’s stunning how accurate this was.
In the early twentieth century, Guy Callendar turned his attention on CO2. In a 1938 paper he showed fuel burning was adding CO2 to the atmosphere faster than the carbon cycle could absorb it. He even went so far as to say this would cause an increase in temperature.
Starting in the 1950s, Charles David Keeling began working on the highly accurate measurements needed to quantify the concentration of CO2 in the atmosphere. Running continuously since 1958, his measurements have proven what Callender estimated in 1938. The plot of these measurements has been enshrined as the “Keeling Curve.” The concentration of CO2 in the atmosphere continues to rise. About 55 percent of CO2 from human activity remains in the atmosphere. It’s been proven this increase in CO2 concentrations will absorb more infrared radiation in the atmosphere, which causes an increase in global temperatures. Further, we can attribute this temperature rise to a variety of global impacts, thanks to high-resolution global scale models that have been running for decades.
Thousands of scientists have diligently pulled these threads over time, knitting together a clear tapestry today:
The carbon cycle and our understanding of how carbon moves through the environment
Properties of CO2 as an energy absorbing gas
Fuel burning and human activity that produces more CO2 than the carbon cycle can absorb
Quantification of rising CO2 levels as shown by the Keeling Curve
Quantification of the heat trapping effects and temperature rise
Attribution of this temperature rise to changes in our climate and impacts on our environment
These are the building blocks of what we know today and what we see is a huge threat to human thriving. You can’t talk about climate change without telling a little bit of this amazing story. Thousands of scientists running a massive relay race over centuries to acquire the knowledge and insight we have today. We are lucky to have it.
These insights are the foundation of the debates we have today. Further discovery of the sources of our emissions, the energy absorbing properties of other gasses, and the interplay of warming the impacts of climate change are all build upon this. Further discoveries about the efficacy of various technologies and policies to mitigate climate change by reducing emissions and removing excess CO2 and other GHG’s from the atmosphere all build on these insights. The relay race continues, branches and forks into new areas of discovery.
Let’s win the race.