Abrupt precipitation changes in the Northeast and Northwest Himalaya during the last millennium using proxy records from lake and cave deposits

Abstract

The precipitation in the Himalayan region is very crucial for the socio-economic well-being of large human population in South Asia as this is the major source of water for most of the perennial rivers in the region like the Ganga, Yamuna, Indus and Brahmaputra River. The Indian summer monsoon (ISM) is the chief source of precipitation in eastern and central Himalaya, and western Himalaya also receives a significant part of moisture by the Mid latitude westerlies (MLW). The changes in the ISM intensity or onset/retrieval in past led to the loss of lives of humans, cattles and property by widespread droughts associated with famines and disastrous floods. But the frequency of these extreme precipitation events in past and their forcing mechanisms are not fully understood due to lack of long term meteorological observations and high resolution paleoclimate records from continental areas in South Asia and especially from the Himalayan region. The last few decades have witnessed several extreme precipitation events in the Indian subcontinent along with the Himalayan region.