Editorial: Effects of warming

The revelation by the India Meteorological Department (IMD) that eight of the 10 warmest years on record since 1901 have been in the last one decade and that all years since 1993, barring one, have clocked higher than normal temperature establish beyond doubt that India's climate has already changed on account of global warming "" and this is irrespective of whether the warming is on the long-term ascendant or cyclical in nature. The extreme weather events experienced in 2007, marked by intense cold spells, severe heat waves, devastating floods and crippling drought in different parts has cost the country dear, in addition to causing over 2,000 deaths. The IMD's latest observations corroborate the ominous projections made in some earlier studies that temperatures in India would soar by 3 to 6 degrees Celsius and monsoon rainfall would be up by 15 to 50 per cent by the end of the 21st century. The worry is that the rise in the sea level as a consequence of the higher temperature "" driven by faster melting of glaciers and higher rainfall "" may alter the country's geography, especially the coast line, by submerging several low-lying coastal areas, including the mangroves-rich Sundarbans. At another level, the disappearance of the river-feeding glaciers may dry up flows in the country's major rivers, including the mighty Ganga, and adversely impact agriculture to the detriment of the millions of farmers who lack the wherewithal to adjust to the changing climate. What is equally unnerving is that overall farm production is forecast to drop by 10 to 40 per cent due to the temperature rise by the end of the century, making the agriculture sector the worst sufferer though its contribution to global warming is relatively meagre. Indeed, the wheat crop has already begun to show this impact as its output remained depressed for several years till 2006 due to the early onset of summer.

 

The silver lining to this disquieting scenario is that some crops, especially summer (kharif) crops like paddy, may benefit from higher temperature. But that would provide cold comfort because the overall adverse effect would far outweigh the minor benefits.