rising India getting less sunshine due to pollution

India may be enjoying an unprecedented economic boom, ( Economic Boom!!! Dont ask me abt that!!! I am still innocent poor ) but the country is also facing a darkening environmental gloom.

Despite the drastic decrease in S, the all India averaged surface maximum and minimum air temperatures have been increasing. But, the change in increase in maximum temperature from the first decade to second decade is only marginal under the present situation of drastic increase in greenhouse gas emissions, while the increase in minimum temperature has been doubled.

A blanket of smog hanging over India means the country is getting less and less sunlight, warn researchers. But this phenomenon, known as “solar dimming” may also protect against global warning.

Monthly mean surface reaching solar radiation (S) measurements under all sky conditions have been evaluated for 12 stations, which are widely distributed over the Indian region, for the period 1981-2004. It is noteworthy that all the stations showed decline in S ranging from −0.17 to −1.44 W/m² per year. The average solar dimming observed over India for the period 1981–2004 is ∼−0.86 W/m² per year while during winter, pre-monsoon and monsoon seasons it is ∼−0.94, ∼−1.04 and ∼−0.74 W/m² per year, respectively. Decadal monthly mean S for the two decades 1981–1990 and 1991–2000 showed strong decline during the second decade with an average reduction of 5% per two decades.

India is getting about 5% less sunlight than it did 20 years ago, according to a study by Padma Kumari and colleagues at the Indian Institute of Tropical Meteorology in Pune. They studied data from the India Meteorological Department, measuring differences in solar radiation at 12 stations across India between 1981 and 2004.

They found that the amount of solar radiation reaching India’s land mass dropped on average by 0.86 watts per square metre each year. The decrease was greater during the 1990s than the 1980s, and on average corresponded to a 5% drop in sunshine over the two decades.

India is losing out on sunshine because a cloud of tiny air-borne particles released by the nation’s industries hovers above the subcontinent, blocking light from reaching the Earth.

See the orignal publication here: http://www.agu.org/pubs/crossref/2007/2007GL031133.shtml