EDITORIAL Global climate change — Dr Kathita Hatibaruah
The Intergovernmental Panel of Climate Change (IPCC), a group established by the World Meteorological Organisation (WMO) and the United Nations Environment Programme (UNEP) have reported that the average surface temperature of the earth has increased during the 20th Century by about 0.6 degree C +- 0.2 degree C which means that average temperature increase might be as low as 0.4 degree C and as high as 0.8 degree C. How the global climate is changing and the role of human activity in these changes coupled with the uncertainties of the global climate has to be explored by the researchers through a continuous non-stop process. The researchers also found that the global climate changes are interconnected with at least four zones: atmosphere, hydrosphere (the earth’s oceans and water), cryosphere (the area of the planet covered by ice) and biosphere (the living organisms inhabiting all these domains). The earth receives tremendous amount of energy from the sun. The land, sea and air absorb some of these energy and reflect some of it back into the space. This process is known as earth’s energy budget. The greenhouse effect is one aspect of this energy budget.
The increase in atmospheric concentration of carbon dioxide and other greenhouse gases strengthens the greenhouse effect which contributes to global warming. Moderate increases in atmospheric temperature could alter precipitation levels, by making some areas of earth wetter and others drier affecting agriculture, flora and fauna worldwide. Again warmer atmosphere could increase the frequency of storms, destructive hurricanes and subsequent flooding. Moreover, slight changes in temperature may lead to higher zone levels near the earth’s surface which increase smog problem in large cities which is bad for human beings, especially the elderly and ill people and physically vulnerable citizens. Again, oceans play a key role in regulating the earth’s climate. Their fundamental role in climate change is based largely on their storage, and transport of heat around the globe. The oceans store a vast amount of heat, much more heat than the atmosphere, because water is one thousand times more dense and has a heat holding capacity four times than that of air. Some researchers opine that a small increase in global temperature could bring a significant rise in sea levels and continuous rise in sea levels could have devastating effect on some islands, such as Maldive islands causing complete devastation of these tiny nations.
Again continued global warming will have effect on world’s polar ice, sea ice, glaciers and permanent snow cover. Therefore, cryosphere also provides a way to study the climatic conditions of the past. Global climate change affects living things also. Plants consume carbon dioxide and produce oxygen through a process of photosynthesis. Atmospheric carbon dioxide can prevent greenhouse effect, because this controversial ‘greening hypothesis’ has led to more research exploring the connection between the global climate and earth’s biological systems which affect vegetation/agriculture etc. Some species need warmer temperature to grow but increase in population of these species may have serious repercussion on human health in the shape of increasing mosquito population in tropical areas leading to transmission of diseases like malaria, dengue fever, elephantiasis, etc. Researchers opine that , especially in relation to the typical temperature changes associated with daily and seasonal cycles, global temperatures are very stable. During the last ice age, about 20,000 years ago, the average global temperature was only about 5 degree C cooler than it is to-day.
The United Nation’s IPCC constituted by the leading scientists in their 20 page Scientific Report in the year 2007 expressed the opinion that global warming is now ‘unequivocal’ and ‘human activity’ is the primary cause of rising temperatures worldwide since 1950 and as a result greenhouse gas emission started today worldwide. They further opine that there is still time to slow down global warming , if we act quickly and thereby to lessen its many severe consequences for the future of our planet. Rising global temperature has direct effect on water supplies and green vegetation like agriculture, etc. Obviously, the deserts will expand the frequency and severity of droughts. And deadly heat waves will increase following the disappearance of snow in most areas except on the very high mountain peaks. Fierce storms, such as hurricanes will become more frequent and more flood will occur causing loss of properties and human lives and bringing in its trail, infectious diseases like malaria, dengue fever, yellow fever, and encephalitis, etc.
The IPCC Report also mentioned that human activities are the major contributing factors to global climate change since the Industrial Revolution of 1750. Global concentration of carbon dioxide, methane and nitrous oxide, (the three notable greenhouse gases has increased significantly over the past 250 years as a direct result of increased human activities. The use of fossil fuel like oil and coal , cutting down of forests for farming, housing for industrial development, etc will have disastrous effect.
Less energy use means less dependence on fossil fuels which create greenhouse gases and contribute to global warming. The role of community education is increasingly being recognised as a strong and worldwide forum for motivating global climate change towards positive and constructive force. What is more important is the political will of the leaders and policy makers of both developed and developing countries. Otherwise, the population of the developing countries will be the worst sufferers or victims of global climate change. Therefore both the developed and developing countries should march together to fulfil the common objective, because human beings are the curators of this globe and for better sustainable development, the need of the hour is to save the globe from the ecological pressures and imbalances. It is an established fact that transfer of toxic materials from developed countries to developing countries, largely chemical by products of industrial process dumped at the sea or transported to poor countries becomes a major global ecological issue. Unless this is squarely addressed, environmental degradation of our common planet will continue to worsen unchecked. The gases already emitted by the industrialised countries during the last 200 years are still retained in the atmosphere causing tremendous damage to the earth’s environment.
Therefore the main global climate change issues of today are ozone layer , greenhouse gases, bio-diversity, transportation of toxic materials, ecological aspect of international trade, international environmental governance, etc. In the early 70’s, atmospheric imbalance drew worldwide attention and as a result, it led to the signing of Montreal protocol in 1987. The Chloro-fluoro-carbons (CFC) had originated from developed countries. Every human being has an equal right to the earth’s atmosphere and responsible for global climate change. No one should be allowed to pollute the atmosphere and its violation should be strictly dealt with. Carbon dioxide and CFC emissions are mostly caused by luxury and convenience consumption , such as through cars, refrigerators and industrial plants, etc. It is also noticed that vast bulk of land is generally distributed between governments and individuals and very little is left under the community care. More than a century ago, land in India was in the care of communities and not owned by governments and individuals. Today, not even 5 per cent of the land in India is effectively under community control. Ecologically, the earth is much safer in their hands than it is in the hands of governments and individuals.
It is a recognised fact that global climate change is one of the most serious threats to the environment. Now is the time to act on global climate change unitedly by both developed and developing countries. While there is need for campaigning to spread environmental literacy or climate literacy through general education programmes among the masses , there is also need for understanding and responding to climate change, viz. “Your climate, your future.” In the context of environmental policy, the term ‘climate change’ usually refers to changes in modern climate. As already stated , the change in climate is caused by many processes both by natural and man-made causes. (The writer is former Vice Principal, Guwahati College)
