Climate on a skid

Climate on a skid global warming over the next century could turn out to be much worse than previously estimated, says the latest report of the uk Met Office's Hadley Centre for Climate Prediction and Research. Even if greenhouse gas ( ghg ) emissions are stabilised (which would require an overnight cut of 60-70 per cent in global carbon dioxide emissions), there would be a 1 degree Celsius rise in atmospheric temperature and a seal level rise of about one metre. Based on the findings of the Intergovernmental Panel on Climate Change ( ipcc ), the centre projects that warming over land would be 80 per cent faster than over sea; the highest emission scenario could lead to a 6 degree Celsius rise in temperature over land by 2100, 2 degree Celsius C higher than previous estimates.

The Earth has a natural abalance of releasing the heat that it absorbs from sunlight.But in recent years there has been an enormous increase in ghg s like carbon dioxide, which trap heat, leading to alarming rise in temperatures. Global warming will also cause large-scale increase in rainfall over India's western coastline, says a joint study by Hadley Centre and the Indian Institute of Technology, New Delhi.


TREES: myths and reality If you think planting more trees to absorb carbon will solve the problem, read the report carefully. Planting trees will absorb carbon dioxide from the atmosphere in some parts of the world, but in others global warming may impede tree growth or even be responsible for their death. Therefore, afforestation may not be a complete solution. There is more for those who swear by forests as 'carbon sinks'. Forest cover is usually darker than the underlying surface, especially when the surface is snow, and absorbs more sunlight than areas with no trees. Hence they might accelerate warming as darker surfaces absorb more sunlight as compared to lighter ones. Different forests reflect differing amounts of sunlight; dark green forests absorb more solar radiation than land surface. Therefore, the beneficial effects of their carbon uptake could be reduced, and in some areas, be reversed by this 'darkening effect'. The findings undermine arguments put forth by industrialised countries like the us , which wants to fulfil a major part of its carbon reduction targets under the 1997 Kyoto Protocol through sinks.
The present scenario Hadley's scientists used the general circulation model ( gcm ) to make their predictions. gcm uses a set of mathematical relationships which represent the major processes in the climate system. They report that global average temperature in 1999 was lower than in the record-breaking year of 1998, but 1999 was still the fifth warmest year since global records began in 1860. The centre has discovered startling evidence that by 2050, the world's trees and soils will start perishing, thus reducing the rate of carbon absorption by the land.

Temperatures were lower in 1999 than in 1998 the tropical Pacific changed from the warm El Ni