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The Financial Express

A brief history of Climate Change

| Updated: January 04, 2022 21:32:47


A brief history of Climate Change

From the Alpine valley where geologist Jean-Pierre Perraudin found a huge boulder  in 1815 and wondered how did it settle there  to the city of Glasgow where the COP-26 the annual conference of countries was held under the UN Framework  Convention on climate change, the physical distance is not much but temporally the two events straddled several centuries. The first was the beginning of the history of climate change and the last, the latest attempt by the world community to come to a consensus on how to write the unfinished history to the benefit of human kind. By geological  time scale, the journey may not have been  for long but it has been both tortuous and arduous.

By late eighteenth century there was increasing acceptance by geologists of  pre-historic epochs after they found evidence of a succession of geologic ages associated with climate change. There were various other competing theories, however, about these changes. A geologist named Buffon thought that Earth had begun as an incandescent gaseous globe with  a mineral core that gradually cooled down. James Hutton, another geologist found signs of glacial activity in places too warm for glaciers. In 1815 Jean-Pierre Perraudin described for the first time how glaciers brought huge boulders to the Alpine valley after ice had melted as a result of atmospheric warming. At first his hypothesis met with disbelief from fellow scientists. Jesn Charpentier, a leading geologist, thought Perraudin's ideas were extravagant and did not merit examination. But persisted in his belief and convinced, Charpentier who in turn convinced the leading geologist of the time, Louise Agassiz that Perraudin's glacial theory had merit and called for further examination. After field visits and examination of evidences Agassiz developed his theory of Ice Ages when Europe and North America were covered under ice. In 1837 he formally announced that the Earth had been through an ice age after which it became warmer as a result of gradual melting of glaciers.

Before the theory of Ice Age was announced, a scientist named Josph Fourrier argued in 1824 that the Earth's atmosphere kept the planet warmer than would be the case in a vacuum i.e., without an atmosphere. He reasoned the atmosphere transmitted  visible light waves 'efficiently' to the earth's surface. The Earth absorbed these visible lights and emitted infra-red radiation in response. But the atmosphere did not transmit infra-red  radiation 'efficiently' which increased the temperature of earth' s surface. He also suspected human activity could influence the radiation balance, and through it the Earth's surface. In 1859, John Tyndell, another leafing scientist, took Fourrier's work one step further when he examined  the absorption of infra-red radiation in different gases. He found that water vapour, hydrocarbons like methane (CH4) and carbon dioxide (CO2) strongly bloc infra-red radiation. Thus emerged the concepts of greenhouse gas, the main contributor to global warming and climate change. But there were dozen other theories which were developed to explain global warming, including volcanic eruptions, shifts in ocean currents, southward polar shifts, pulls by sun and moon etc. Thus climatology or the science of climate change began as early as the middle of eighteenth century, competing theories made conclusions by scientists anything but unanimous. More importantly, the lack of evidence to show catastrophic changes having already taken place or about to occur in near future failed to engender a sense of urgency among policy makers and coordinated investigation by countries.

The next momentous finding on climate change was made by Svante Arrhenius in 1896 when he calculated the effect of doubling of carbon dioxide (CO2) in atmosphere to be the main cause for increase in earth's surface temperature by 5 to 6 degree celsius, a function which none of the other green house gases were to have. In 1902 Arrhenius wrote an article in which he attributed carbon dioxide as the main contributor to global warming and identified coal as the main source of CO2. He even went to the extent of observing that coal combustion would lead to the extinction of human race. But he estimated apocalyptic moment to arrive not before thousand of years. John Tyndell's observations did not find support among majority of scientists, particularly about the harmful effects of use of coal and its production of carbon dioxide. Even those who were convinced took comfort from the fact that nothing risky to human life would take place before thousands of years, which made global warming only a subject of academic. interest. Given this state of the science of climate change at the turn of nineteen century and the confusion created by disputes and lack of unanimity among scientists, climate change as a crisis did not make any serious impression among policy makers or in the corridors of power.

In 1938, a scientist named Guy Stewart Callendar attempted to revive Arrhenius's Green House Effect Theory, based on his professional interest, and not because of any new sense of urgency necessitated by developments in real life. Climate change as a threat to life and livelihood did not register on the minds of policy makers. Firstly, because no catastrophe had taken place that could be attributed to global warming. Global warming  was progressing inexorably, but slowly without creating emergency in the short term. Secondly, the scientific community was still divided  over the cause of global warming, particularly in respect of coal. Callendar presented evidence that both temperature and CO2 levels in atmosphere were rising over the past half century. Most scientists still continued to dispute his theory questioning the reliability of the evidences. Better measurement techniques in 1950s showed that CO2 and water vapour absorption lines did not overlap. Climatologists also realised little water vapour was put in the upper atmosphere. Both the discoveries showed that the CO2 greenhouse effect would not be overwhelmed by water vapour as was thought earlier. In 1957 better understanding of ocean chemistry led to realisation that ocean surface layer had limited capacity to absorb CO2 and such could not reduce the increase in its level. By late 1950s many scientists were saying that CO2 would be a problem with some predicting that CO2 would rise by 25 per cent by the year 2000 with potentially radical effects on climate.

With the availability of computer scientists began to develop more sophisticated versions of Arrhenius's calculations on greenhouse effect of coal use. In 1967 using digital computer, two scientists, Manabe and Wetherald made the calculation that showed that in the absence of unknown feedbacks such ad clouds, a doubling of CO2 from the current levels would result in approximately 2 degree celsius increase in global temperature. But the red herring of smog that was becoming pollution problem in some cities led scientists to argue that the cooling effect of smog could counter rise in globa temperature. But they were not sure whether cooling effect would overwhelm greenhouse effect. In the midst of this confusion some scientists claimed that human emissions could be disruptive to climate in the 21st century.

A more reliable source to know the realistic scenario about global warming than the conflicting theories and predictions of scientists was made available by World Weather Records which initiated a record of global temperature in 1938 involving data from 200 weather stations. The first up to date temperature reconstructions were completed in 1963.The data collected were used to calculate latitudinal average temperature. The result of this study showed that beginning in 1880 global temperature began to increase steadily until 1940. After that a multi-decade cooling trend emerged. The study created further confusion as media like the Newsweek brought out an issue captioned, 'Cooling Earth'. Fortunately, the red herring was countered by a report prepared by the Science Advisory Committee of US President Lyndon B. Johnson in 1965.Though the focus of the Report was on the protection of environment. The Committee used the global temperature reconstructions and carbon dioxide data from the study of the World Weather Records to reach their conclusions. They declared the rise of atmospheric carbon dioxide tends to be the direct result of fossil fuel burning and concluded that human activities were sufficiently large to have significant global impact, beyond the areas those activities take place. Though no recommendation was made to cut the use of fossil fuel the American oil companies took alarm and prepared to lobby any restraint on the industry. The American scientists worked in good faith  but political consideration did not allow the American President  to take any action beyond environmental ones, like national parks, clean air and water. Sixties were the time when environmental issues and sustainable development took the centre stage nationally and internationally.

Ironically, the first international event dealing with climate change was held in 1969 under the auspices of a military alliance the North Atlantic Treaty Organisation that felt issues like acid rain, climate change, environmental degradation fell within its remit. It was obvious that the organisation looked at the emerging issues from the perspective of security. The American President Richard Nixon tried to manipulate the agenda keeping cold war at the centre stage but he was upstaged by German Chancellor Willy Brandt who succeeded in orienting the agenda towards international concern which resulted in convening the Stockholm UN Conference on Human environment in 1970, precursor to UN's involvement with climate crisis. Soon the concern for the creeping crisis got boost from other international fora.

The Club of Rome, an European response to address the problem of environmental degradation and its impact on sustainable development produced two reports in 1972 and 1974 where the anthropogenic (man- made)  contribution to CO2 increase was highlighted. Almost around the same time the scientists duo-- Manabe and Wetherald developed a three dimensional global model that gave a more accurate representation of current climate situation. Their model showed, doubling CO2 in the atmosphere, gave a roughly 2 degree selsius rise in temperature. Similar attempts by scientists showed that it was impossible to make a model that gave something resembling the actual climate and not have the temperature rise when CO2 concentration was increased. As a corollary to this finding the harmful effect of burning fossil fuels was also brought under spotlight.

In 1979 the first world climate conference was held under the aegis of the World Meteorological Organisation, a UN body where it was observed that an increased amount of CO2 can contribute to a gradual warming of lower atmosphere. Based on this, it was concluded that some adverse  effects on a regional and global scale may be detectable before the end of twentieth century and become critical before the middle of the 21st century.

In 1979, a few months after the World Climate Report, the US National  Research Council published a report concluding that when CO2 content of the atmosphere is doubled, the thermal equilibrium will be so interfered as to produce a global surface warming between 2 degree celsius to 3.5 degree celsius. Thus, both individual scientists and reputed research bodies veered to the same conclusion about CO2 increase and its impact on global warming and giving statistical number to quantify the degree of increase.

Beginning from.1980s two UN bodies, the World Meteorological Organisation (WMO) and newly established UNEP (for environmental protection) began issuing reports that not only warned about growing global warming but also highlighted the increasing level of greenhouse gas, particularly, CO2 caused by fossil fuel burning. In the process the countries  burning most fossil fuels, America and China, were identified. Faced with backlash from other countries that could put restraint on its giant oil companies and coal industry America under President Ronald Reagan  pressurised the UN to have a convention for annual discussion of the problem by member countries and thus stop bodies like WMO and UNEP from making random forecasts and urging drastic action to cut carbon emissions. The pressure brought to bear on the UN to take preventive (mitigation) and remedial actions (adaptation) by countries like Bangladesh and Maldives, which were on the frontline of climate change related crisis (loss of coastal land as a result of sea level rise from melting of ice) also acted as a spur on UN to institutionalise the deliberations on climate change. As a result the UN Framework Convention on Climate change came into being with the mandate to hold annual Conference of the Parties (COP).The last of this conference was held in Glasgow in November this year. To help the member countries with the latest scientific information and data on climate change the UN has constituted an expert committee  named Intergovernmental Panel on Climate Change (IPCC). Its members are nominated by member countries and work part-time to prepare working papers (Assessment Report) based on peer- reviewed articles published by reputed scientists around the world. This systematic arrangement  for deliberations by political leaders is flawed by the fact that reports submitted to COP has to be unanimous. This results in forced regimentation  of thought and superficial uniformity of views. It is not infrequent that uncomfortable scientific facts and objective recommendations of scientists are omitted for the sake of consensus.

Climate change history and science have come a long way since Charles-Pierrre Persudin looked at a huge boulder in Alpine volley and set the scientific ball rolling to investigate the geological change which led to theories of global warming and climate change. Even after sanitisation of facts and figures the information that is irrefutable points to existential threat to human race and other species in the not too distant future. But the staggered nature of the impending doom  that allows grace time to the major contributor to the crisis has prevented a reasonably time-bound plan of action to be taken in earnest. All that emerged from COPs are declaration of intent and exercises in semantics. 'Phasing out' or 'Phasing down?' of coal use, on that Shakespeare-like dilemma (puzzle?) ended the much-hyped COP-26. Climate science continues to be given lip service even at this stage when the enemy is at the gate. The situation is too bad to be true. 

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