The consequence of worldwide pollution from man's lazy use of fuel was highlighted again today by NASA. The earth's ice cover isn't reflecting enough sunshine. Soot from poorly burnt diesel fuel, coal, dung and heavy oil falls out of the air constantly.


It is well known that the albedo, or brightness, of the white stuff should reflect 98% of the sunlight and heat that reaches it. To some degree this counteracts the natural warming effect of the greenhouse gases. It is obvious then that if the snow and ice aren't quite as shiny as they should be, because they've got a covering of darker pollutant, then there is a net warming effect on the atmosphere.

This is accounted for in the computer models run by the Met Office's Hadley Centre and can be adjusted. NASA's scientists have evidence that suggests 25% of the global warming in the last century may well be due to soot deposits on ice and snow. This, as they point out, means that greenhouse gases still are responsible for 75% of the temperature rise.

Some work is being done to reduce the burgeoning plume of pollution: Natural gas is replacing two-stroke power in Dhaka, Bangladesh. Bangkok's tuk-tuks are now on LPG and the belching diesel buses of Bombay and New Delhi are changing to natural gas. In the US emission controls are tightening and the existing technology is being exported to developing nations.

For the immediate future, the trend is the wrong way and today northern india is suffering again as a cold fog sits in Uttar Pradesh. As was easily shown in London before the clean air act, fog forms more easily and densely in polluted areas.

Related Links :
www.nasa.gov

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