The analysis of Glaciers and Snow cover has been made using different data sets of varying length.
1. The areal extent of glaciers in the Himalayas is estimated as 24,697 ± 3,260 Km2.
2. Glacier retreat is estimated by numerous investigations and the mean loss for 83 glaciers for past four decades is estimated at 550 ± 419 m.
3. The retreat estimation has high uncertainty due to large variability in individual retreat.
4. An overall loss of area of 12.6 ± 7.5 % for 40 years from 1960 onwards.
5. The mass balance data is available for few glaciers and cumulative mass loss for the past 44 years is estimated as 20 ± 6 m.
6. The average snow cover in the Himalaya from 2000 to 2011 varied between *0.3 and 0.03 million km2. The average volume of snow is estimated at *54.5, *9.3 and *14.5 billion cubic metres in the Indus, Ganga and Brahmaputra basins, respectively
The analysis of atmospheric aerosols is made using different data sets of varying
1. There is a phenomenal increase in aerosol loading over India. There is a statistically significant increasing trend in aerosol optical depth over India with a significant seasonal variability.
2. Seasonally, the rate of increase is consistently high during the dry months (from December to March). The trends are weak during the pre-monsoon and monsoon seasons.
3. There is a clear evidence of effect of anthropogenic activities in increase of aerosol loading.
4. Black carbon observations at a remote coastal location shows a decreasing trend, which is perceptible after 2004.