What is climate change?
‘Climate change’, is the term given to change in the weather patterns in a particular area or region for a significant period of time. Climate change results in abnormal variations in the climate, and affects areas of the planet. Over a 100 years ago, two scientists, French researcher, Jean Baptiste Fourier and Swedish scientist, Svante Arrhenius, discovered that an increase in the levels of carbon dioxide warms the entire planet. Their discovery of what came to be known as the ‘the greenhouse effect’, applies to both natural and man made emissions of CO². Levels of carbon dioxide in the atmosphere showed a steady increase after World War II. Earth system scientists started looking for a parallel increase in temperature, basing their studies on the governing laws of the greenhouse effect. By the early 1980s, the climate scientists were referring to the atmospheric response as global warming. Not all areas of the planet were expected to experience the same extent of increase in temperature nor was an increase in temperature the only anticipated impact. This rise in temperature and an addition of acidity to the oceans of the planet has vast effects that are changing the climate conditions that we are used to and on which we have based our agriculture, industry and social systems.
What do you need to know?
In recent times, we are experiencing climate change, mainly due to global warming. Kolkata, India, is experiencing its hottest year yet. This sudden change has been brought about by global warming. Some of the indirect effects of global warming are as follows:
• As the northern countries get warmer, insects carrying plague and disease migrate to them. Some scientists believe that in some countries, due to global warming, Malaria has not been completely eradicated.
• As the temperatures of the oceans rise, hurricanes and cyclones will become more frequent, the last of which (Aila) tore through Bengal on 25 May, 2009.
• Global warming may cause some areas of our planet to become wetter, but others will suffer a severe series of droughts and heat waves. Serious droughts are expected in Europe, but Africa is to get the worst of it. According to the Intergovermental Panel on Climate Change, the condition could lead to conflicts and war.
• Global warming will have economic consequences as well. The estimated amount needed to treat diseases and repair damages brought about by hurricanes run into billions of dollars.
• The polar ice caps will melt. This in itself will have effects of its own.
- 5,773,000 cubic miles of water, make up the ice caps. If they melt, the sea level will
rise by about 230 feet. It may not happen all in one go, but the sea levels will rise
- Rises in temperature and changing landscapes in the Arctic Circle, will endanger
many species of animals; the polar bear for instance. Only the most adaptable
species will survive.
- Loss of the ice caps could bring about global warming faster. The white ice caps act as reflectors, sending some of the sun’s heat back.
With them gone however, the only reflector will be the ocean, whose dark colours will
absorb the heat, making the planet hotter still.
What can you do?
Contribute to the cutting down of pollution. If one person starts doing his bit to cut down on pollution, it won't make much of a difference immediately, but it will get the ball rolling. If others follow suit, and a large group of people begin to take care not to use products that are non-biodegradable, and to remember to switch off lights, fans, electrical appliances, etc., it could make a huge difference to the health of the planet.
• “Carbon Shift: How the Twin Crises of Oil Depletion and Climate Change Will Define the Future” by Thomas Homer-Dixon, published by Random House. Canada.
• “Heatstroke” by Anthony D. Barnosky, published by Island Press.
• “Climate Wars” by Gwynne Dyer, published by Random House Canada.
• The Long Thaw by David Archer, published by Princeton.
• “Dire Predictions: Understanding Global Warming” by Michael E. Mann & Lee R. Kump, published by DK Publishing (Dorling Kindersley).
See & Hear
• “An Inconvenient Truth” - Al Gore
• “Home” - Yann Arthus-Bertrand
On the Web
• How much have sea water levels risen in the past century?
The rate of increase had been 1.8mm per year for the past century and has recently risen to 2.8mm per year (1993-2003).
• How much has the average global temperature increased in the last century?
Averaged over all land and ocean surfaces, temperatures have warmed roughly 1.33°F (0.74ºC) over the last century.