Weather Systems over Himalaya: Cloud and Precipitation Processes

Himalayan region mainly consisting of fragile mountain systems is very sensitive and venerable to the climate change that possesses a serious threat to the livelihood and socioeconomic activities of the population residing in the Himalayan states, for example, cloudbursts and flash floods as a result of heavy rain are commonly observed during Indian summer monsoon season. This chapter delineates about the Himalayan weather systems, cloud and precipitation processes, and their microphysics. The various types of ice crystals synthesized in a laboratory environment are also presented to understand formation mechanism of hydrometeors inside the clouds. The Mountain topography plays an important role in modulating the large horizontal flows and influences the diurnal variability of wind locally around and along the mountain slopes. Some examples of occasional fronts observed over a central Himalayan site during different seasons are also presented here. The events discussed are based on the micrometeorological observations made over the high altitude site mentioned here. The analysis shows that frontal activities in spring and summer seasons are dominant as compared to winter and series of fronts are observed during every month from March to June of 2014. During these episodes, the cold air mass suddenly replaces the warm air with rapid fall in temperature of the order of 5–10°. The intensity of the front observed in winter is much higher than those observed in spring and summer.