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Climatic upheaval in the offing?
While earthquakes, such as the one that ravaged northern Pakistan, are unlikely to be related to climatic changes, hurricanes may be a different story. The generation of Katrina and Wilma has been blamed by meteorologists on the progressively rising temperatures in the sea
IS OUR planet heading for a climatic upheaval? Based on the evidence available, the answer seems to be in the affirmative but no one knows for certain.
The findings reported recently by the National Aeronautical and Space Administration’s Goddard Institute for Space Research point towards some disturbing trends in the world climate. The year 2005 has seen an inordinate number of natural disasters, a tsunami, hurricanes, and devastating earthquakes striking different parts of the globe. Their frequency and ferocity have intrigued and baffled many.
While earthquakes, such as the one that ravaged northern Pakistan and those that triggered the destructive tidal waves in South East Asia, are unlikely to be related to climatic changes, hurricanes may be a different story. The generation of Katrina, Wilma and a number of others which hit southwestern United States this year has been blamed by meteorologists on the progressively rising temperatures of waters in the Gulf of Mexico.
According to the National Oceanic and Atmospheric Administration, the summer water temperature in the Gulf was the highest recorded during the last 100 years. Even more significantly, 2005 has been the warmest year since the climatologists started keeping records, a finding consistent with the observed pattern of rising temperatures seen in the past few years.
The increase in global temperature is small, only 1.36 degrees Fahrenheit above the average temperature measured during the thirty years from 1950 to 1980. On the face of it, this small increase seems negligible, hardly worth worrying about.
However, scientist are concerned that the rate of warming will accelerate with time and the cumulative effect of an increasingly warmer climate will have farreaching and profound consequences for the inhabitants of our planet. There are indications that this phenomenon is already having an effect.
In its Nov 17 issue, the British journal Nature published data collected by the World Health Organization which indicated that global warming had contributed to an estimated 150,000 deaths and more than 5 million cases of illness, brought about by diseases like malaria, diarrhoea and malnutrition. Dr Jonathan Patz and colleagues — authors of the Nature article — speculate that the damaging effect of climatic changes will double within the next 25 years.
The irony of the situation is that the poorer countries of the world, which contribute very little to the atmospheric pollution, suffer most of the adverse consequences. According to the WHO study, the United States and China are the two premier polluters, each emitting 1,591 and 755 million metric tonnes, respectively, of carbon dioxide into the atmosphere. However, countries exposed to the most harmful effects are poor countries of sub-Saharan Africa, South American Pacific Coast and South Asia, namely India, Pakistan, Bangladesh and Indonesia. The recent outbreak of dengue fever, a mosquito-borne tropical illness that killed an estimated 1,000 people in some countries of South Asia is attributed to the accumulation of greenhouse gasses.
In Peru the warming effect, brought on by the Ocean current know as El Nino, is known to have led to a sharply increased rate of hospitalization among children. Apparently, as temperatures rise, the parasites responsible for malaria and other pathogens grow at an accelerated pace. In a recent article in the Washington Post, Patrick Kinney, a professor at Columbia University, was quoted as predicting that global warming could cause an increase in smog-related deaths in New York City alone by 4.5 per cent in the next fifty years.
The global greenhouse effect, strangely, does not impact on the Earth’s surface equally or uniformly. Its effect on the northern hemisphere is disproportionately large, compared to the southern hemisphere. Unlike ice, water absorbs heat rather than reflecting it.
Normally, much of the Sun’s heat and light is reflected back into space by the thick ice mass which covers the Arctic Ocean throughout the year, but when a significant part of it thaws and becomes water, it promotes a universal warming effect.
The North Pole is now retaining so much solar radiation that its huge arctic ice caps are progressively melting and the vast northern glaciers which had remained intact for millennia are slowly retreating. Scientists have estimated that the total area normally covered with ice at the North Pole shrunk in size last summer by 500,000 square miles.
Consequently, the area that remained under ice is the smallest ever recorded. This major loss of ice mass is not without consequence. For Arctic mammals, such as polar bears, the climate change might spell disaster, while for millions of people living within the Arctic Circle who survive mainly by fishing and hunting, it might lead to a severe disruption of their ancient way of life. Much like the polar ice caps, glaciers in the mighty Himalayan mountains are melting, and both Nepal and Tibet are being deluged by floods.
Meanwhile, there is no unanimity of opinion about the reasons behind Earth’s rising temperatures. Indeed, some climatologists believe that it is merely a manifestation of its normal warming and cooling cycles which our planet periodically undergoes and over which we have little control. A majority, however, disagrees with this thesis and blames the warming trend on human activities, such as burning of petroleum and natural gas, which cause excessive emission of carbon dioxide and other greenhouse gases. These gases accumulate in the atmosphere and trap the Sun’s radiation, preventing it from escaping back into space, igniting a warming cycle. It has been estimated that since the start of the industrial revolution in late eighteenth century, the concentration of carbon dioxide in the atmosphere has risen by more than 30 per cent.
To be sure, the international community has not been entirely indifferent in the face of the growing threat from global warming. In 1997, an agreement was reached in Kyoto, Japan, now widely known as Kyoto Treaty that obliged the industrial countries of the world to reduce their emission of greenhouse gases, mostly carbon dioxide, in the next ten years by 5.2 per cent. The most recent studies published in the journal Science by European scientists indicate that the atmospheric levels of greenhouse gases, carbon dioxide and methane, are higher than anytime during the last 650,000 years of our history.
Now, 141 countries, including Russia, which together are responsible for some 55 per cent of atmospheric pollution, have ratified the treaty. Unfortunately, the United States which is responsible for the highest levels of gas emissions has declined to do so. Some large countries — including India, and Brazil — are also not abiding by the treaty at the moment.
Not everyone is unhappy with the warming phenomenon, however. The retreating ice at the North Pole troubles the environmentalists and climatologists; but, it promises unprecedented moneymaking opportunities for entrepreneurs in the rich countries bordering the Arctic Ocean.
The prospects of exploring huge oil, gas and mineral deposits under the ocean floor are luring businesspeople in American, Russia, Canada and Scandinavia, countries that are already staking their claims on the various segments of the ocean. They are betting that as the ice retreats, it will become a lot cheaper and easier to explore for and mine the petroleum and gas reserves in this vast desolate land. Others are eyeing different possibilities, such as dramatically shorter sea routes via the North Pole for shipping which could save millions of dollars in transportation costs for many industries.
Whether the warming trend is driven by human activities or is just a manifestation of the Earth’s natural temperature cycles, the long-term consequences for mankind are likely to be profound and unpredictable.
The writer works as a health science administrator for the National Institutes of Health, Maryland, United States. His email address is amirs@csr.nih.gov
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