The 6 Cs: Climate, Consequences, Chance, Circulation, Change and CFCs

The climate is increasingly more delicate due to human interactions with earth systems. We have entered the Anthropocene a world that is home to disappearing ice, high levels of greenhouse gases, rising temperatures, and uncertainty about what lies ahead for earth. Journalist Fred Pearce explores current climate science, discussing how the climate has changed in the past combined with modern scientific knowledge. Pearce takes a journalistic approach to telling the stories behind the people and their work to discover how the earth has worked in the past and what that can tell us about the future.

In the late 1920s Charles Midgley developed Freon and chlorofluorocarbons (CFCs) that would eventually create the ozone hole over Antarctica discovered by Joe Farman in the 1980s. Three years after Farman’s discovery, the international community recognized the importance of the ozone hole, which led delegates to sign the Montreal Protocol. However, if Midgley had chosen to use bromine instead of chlorine in his refrigerant, the ozone would have been in much worse shape by the time Farman noticed the hole in 1982. According to Pearce, if Midgley had chosen bromine in his refrigerant instead of chlorine the effects could have been one hundred times worse due to bromines ability to destroy ozone given proper temperatures and sunlight conditions.

In his conclusion, Pearce warns that we are ending one of two known periods of climate stability in the past 100,000 years, pushing the climate over a tipping point towards a hothouse climate. He speculates about the possibility of an ocean circulation shut down in the North Atlantic, with warmer water no longer being able to sink into the depths of the arctic to appear two thousand years later in the pacific. If the great climate moderator does shut down, civilization as we know it will follow suite. Our current society will not be able to survive without the ocean circulation currently in affect, the gulfstream could disappear and Europe would freeze. Scientists don’t yet know what the tipping point could be, possibly when the Greenland ice sheet goes and an influx of fresh water cuts off thermo-haline circulation. Whatever the tipping point may be, it would be disastrous for life as we know it.

Pearce does a satisfactory job at compiling significant milestones in climate history, while helping readers understand the immensity of geologic time during which the climate has fluctuated. However, our current scientific knowledge around the intricacies of climate change is not well communicated to lay readers. This may represent the complexities of the current climate crisis, but does not communicate the urgency with which we must act to combat the situation. This is a point that we ought to develop as a society; we must begin to educate the general public about climate and atmospheric science because as a population we must understand the problems presented before we can act on them.

Bibliography and resources

Broecker, Wallace S. “Thermohaline circulation, the Achilles heel of our climate system: Will man-made CO2 upset the current balance?.” Science 278.5343 (1997): 1582-1588.

Farman, J. C., B. G. Gardiner, and J. D. Shanklin. Large losses of total ozone in Antarctica reveal seasonal ClOx/NOx interaction. 1985.

Joughin, Ian, Benjamin E. Smith, and Brooke Medley. “Marine Ice Sheet Collapse Potentially Under Way for the Thwaites Glacier Basin, West Antarctica.” Science 344.6185 (2014): 735-738.

Mann, Michael E., Raymond S. Bradley, and Malcolm K. Hughes. “Global-scale temperature patterns and climate forcing over the past six centuries.” Nature392.6678 (1998): 779-787.

Steffen, Will, Paul J. Crutzen, and John R. McNeill. “The Anthropocene: are humans now overwhelming the great forces of nature.” Ambio: A Journal of the Human Environment 36.8 (2007): 614-621.