Climate is a major driver of forest species distributions and the growth rate and structure of forests. Thus, climate change can potentially have significant effects on mountain forest hydrology, particularly the amount of water available downstream. However, many other factors influence forest biomass and mountain hydrology, and climate change effects cannot be viewed in isolation from previous land use histories (i.e. forest legacies), altered disturbance regimes (e.g. fire frequency, insect outbreaks, floods) and invasive species.

Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m2 per decade since 1988. Results from current climate models indicate that water vapor increases of this magnitude cannot be explained by climate noise alone. In a formal detection and attribution analysis using the pooled results from 22 different climate models, the simulated “fingerprint” pattern of anthropogenically caused changes in water vapor is identifiable with high statistical confidence in the SSM/I data.

Mean-sea-level data from coastal tide gauges in the north Indian Ocean were used to show that low-frequency variability is consistent among the stations in the basin. Statistically significant trends obtained from records longer than 40 years yielded sea-level-rise estimates between 1.06

The two most important hydrological extremes are floods and droughts. These events pose serious hazards to human populations in many parts of the world. These water related disasters are caused because of large diversity in climate and topography of the country. Climate change in future is expected to have severe implications on river flows in South Asia including India. Global climate change is likely to result in severe droughts and floods in India, with major impacts on human health and food supplies.

The vegetation of India evolved in time and space due to geomorphologic changes and the interactions of climate and biotic changes. There is a close linkage between climate and biota. Jul-Dec 2007