In the mid-1970s the evidence about the greenhouse effect and its effect to climate change was growing among the scientific community. Data showed a steady increase of CO2 (carbon dioxide) in the atmosphere during the twentieth century at a rate of 25 times the historical average. Scientists, influenced by the work of Callendar, Revelle, Suess and Keeling have started to wonder if the worming trend which was occurring in the twentieth century was indeed, due to industrial emissions of greenhouse gases like CO2. At the same time, they discovered that the biological productivity of the oceans was an important regulator of the way the CO2 built up in the atmosphere, and that the water vapour which had been found to be an important factor in the formation of clouds, could also play a role in the modulation of weather and climate. And as the questions multiplied, scientists were starting to realise that only an interdisciplinary research programme could provide the much needed answers.
As early as October, 1970, at a conference on “Technological Changes and the Human Environment” at the California Institute of Technology, Thomas Malone, founding Secretary General of ICSU’s Scientific Committee on Problems of the Environment, asked in his keynote address for an “intensive study” of the greenhouse effect which is generated by the combustion of fossil fuels. In 1977 Roger Revelle highlighted the same issue from his role as a Chairman of the Geophysics Study Committee of the Geophysics Research Board in the National Research Council (NRC). Characteristically, in the Committee’s report “Energy and Climate” he wrote that the industrial civilisation “may face a major decision over the next few decades – whether to continue reliance on fossil fuels as principal sources of energy or to invest the research and engineering effort, and the capital, that will make it possible to substitute other energy sources for fossil fuels within the next 50 years.”
Meanwhile, other environmental issues like deforestation and desertification grabbed the attention of the scientists. Connecting these changes in nature with the greenhouse effect they suggested that it constituted what they called “global change” a phenomenon that altered the planet and needed to be understood. During the same period a series of natural disasters across the world, such as droughts and famine in Africa, the collapse of the Soviet grain harvest, and extreme winter and summer weather in the U.S made the headiness all over the world and draw the interest of the environmental groups which increasingly focused their campaigns on inadvertent climate change as the ultimate environmental problem. Recognising the significance of climate change to earth’s viability, the U.S. and the then U.S.S.R. signed, in 1972, an agreement on the Protection of the Environment and formed a Working Group whose purpose was to deal with the influence of the environment on climate. The group’s activities included the study and the monitor of the changing levels of atmospheric constituents that might modify climate, the study of the effects of contamination of the upper atmosphere on climate and the development of climate modelling. One of its most productive programmes was Paleoclimatology. In the Group’s second meeting in 1976 in Princeton, it was agreed that the study on the climate of the late Pleistocene and Holocene eras, was a matter of high priority and a way to understand natural climate variability. In its third meeting which was held in Leningrad (now Saint Petersburg), on 13-21 June 1981, the Working Group produced a report which was published both in English and Russian and concluded that the levels of CO2 in the atmosphere as a result of fossil fuel combustion are rising at a rate that makes their significant influence on global climate more certain. By studying climate models the Group showed that higher concentration of CO2 and therefore warming is likely to occur and they warned that such warming could have important consequences on the biosphere, agricultural and other economic activities. It concluded that in order “to anticipate these consequences in useful detail” it was necessary to understand climate and that required “the full effort of the international scientific community”.
Weather satellites and highly sophisticated space and data management technologies were the most advanced tools to study and monitor global climate because they could provide quick information on large portions of the atmosphere and biosphere. The scientists who participated at the Global Atmospheric Research Programme (GARP), the first international programme to study the predictability of the atmosphere, proposed the development of a ring of five geosynchronous satellites that would be monitored through international cooperation.
These proposals may have been seemed as science fiction to many, especially politicians, but the advances in technology had made possible the realisation of such a programme. Some of these technologies were developed by NASA for space satellites and their applications to earthly satellites could generate valuable data and comprehensive views of the complicated and dynamic earth system. Scientists were already dreaming about ambitious research programmes and applications, that would enable them to observe all the parts that affected the earth system – climate and weather, the atmosphere, oceans and the solid earth, plants, animals and the human activities, all could now be simultaneously researched and studied. At the same time, computer climate models could help scientists investigate the dynamics of the atmosphere and its interactions with oceans and land masses while the increased computer power had made possible to process the data from space-based observations.
Image: Best known as weather satellite, GOES (Geostationary Operational Environmental Satellite) was lunched on October 1975.