In 1896, the Swedish meteorologist Svante Arrhenius calculated that the industrial production of CO2 was enough to change the climate in the coming decades. That assumption was based on earlier findings that CO2 was able to absorb heat (John Tyndall). Arrhenius’ calculations were not much considered in his time even so they were remarkably accurate from a nowadays view on the issue. The lack of modern communication technology did not give him the possibility to spread the word widely. In addition, in the following decades, humankind was much occupied with itself waring through two world wars, recovering from them and also adapting to the many new technological developments.
In the scientific world, the topic of climate change was not forgotten. In 1957, Hans Suess and Roger Revelle published “Carbon Dioxide Exchange Between Atmosphere and Ocean and the Question of an Increase of Atmospheric CO2 during the Past Decades”. They wrote: “over the past 50 years it can be concluded that the average lifetime of a CO2 molecule in the atmosphere before it is dissolved into the sea is of the order of 10 years. This means that most of the CO2 released by artificial fuel combustion since the beginning of the industrial revolution must have been absorbed by the oceans. The increase of atmospheric CO2 from this cause is at present small but may become significant during future decades if industrial fuel combustion continues to rise exponentially.” They showed the estimations of CO2 release into the atmosphere since industrialization has started (Table below).
In for scientists typical manner, they concluded that “In contemplating the probably large increase in CO2 production by fossil fuel combustion in coming decades we conclude that a total increase of 20 to 40 % in atmospheric CO2 can be anticipated. This should certainly be adequate to allow a determination of the effects, if any, of changes in atmospheric carbon dioxide on weather and climate through out the earth”. Between 1900 and 1970, more than 16.000 scientific articles have dealt with carbon dioxide emissions, but only 915 scientific articles linked CO2 emissions up to climate change.
The climate change issue only soured up again when the US government publication EPA-600/7-78-019 from February 1978 got some unexpected attention. At that time, I was 7 years old and discovered the world around me without giving thoughts to global issues. I was in school just for about 1 year and there was so much to learn. The climate change issue was lost on me at that time, and it would actually have been lost on mankind, if not of one careful reader of the government report – Rafe Pomerance. He stumbled over the report’s authors remarks that in the 20 – 30 years to come, the emission of CO2 through the use of fossil fuels might cause significant and damaging changes to the global atmosphere. 20 years from 1978 is 1998, 30 years plus bring us to year 2008. The work of scientists James Hansen, Charles Keeling and other geophysicist received more attention as Rafe Pomerance ringed the alarm bells. Not going into much details here, but check out Losing Earth for those, there were many important and less important meetings with politicians, scientists and industrialists, and important press coverage. Despite the efforts, there was no international treaty on reducing CO2 emissions.The Keeling curve kept on rising (Fig 1).
Fig 1: The earth breathing - The increase in total CO2 breaks with at least 800,000 years of history. Further, increased CO2 is changing the way that plants absorb and emit CO2, and that in turn is altering a seasonal cycle that has been unchanged for hundreds of millions of years. So, the curve above is actually not showing earth breathing, but hyperventilating. (Source from https://climateandcapitalism.com/2018/04/24/the-keeling-curve-a-portrait-of-climate-crisis/)
In the year I was turning 18 (1988), I remember the discussion around the Ozone hole discussion and the responsibility of FCKW (Fluorchlorkohlenwasserstoffe (German: Chlorofluorocarbon)). The Ozone hole led to an international treaty to reduce the production of Chlorofluorocarbons to heal the world from its atmospheric hole. The effort might have exhausted politics, as in the same year, James Hanson made his yet strongest statement in the US Capitol in regard to Climate Change: “The global warming is now large enough that we can ascribe with a high degree of confidence a cause-and-effect relationship to the greenhouse effect.” So, in 1988 global warming left the noise behind and became a scientifically proven fact. Politically it took until 2015 to negotiate what is known as Paris Agreement (signed in 2016 by the UN member states) to dealing with greenhouse-gas-emissions mitigation, adaptation, and finance. My idea why it took so long in one of my future blogs.