IIT-B study explores why South Asian countries face extreme heat waves

Researchers at the Indian Institute of Technology Bombay IITB have found different climatic drivers behind backtoback extreme heat events experienced by South Asian countries including India Pakistan and AfghanistanThe study in collaboration with a team from Johannes GutenbergUniversity Mainz in Germany focussed on unusually intense heatwave events in March and April of 2022The team found different atmospheric processes that compounded heatwave impacts leading to temperatures far exceeding typical ranges for that time of yearOur analysis shows that the March heatwave was primarily linked to a sudden increase in the amplitude of shortlived atmospheric Rossby waves which are largescale meanders in highaltitude winds resembling bends in a winding river said lead author Roshan Jha doctoral student at the Centre for Climate Studies IIT BombayThe waves grew stronger as highaltitude westerly winds near the poles extratropical jet stream transferred energy to westerly winds closer to the equator subtropical jet stream as they came closer during the heatwave Jha addedThe study published in the Journal of Geophysical Research Atmospheres showed that the April heatwave happened differently Instead of being driven by wind patterns in high altitudes it was largely caused by very dry soil conditions and the advection of heat to India from northwestern land regions of Pakistan and AfghanistanImportantly these dry conditions were partly created by the earlier March heatwave which had already dried out the land through high temperatures and clear skiesThe research reveals a concerning pattern one heatwave can set the stage for another more intense heat event in the following weeks by removing moisture from the soil When soil becomes too dry it creates a cycle that makes the next heatwave even worseThink of it like this when the soil has moisture under the clear sky conditions some of the suns energy goes into evaporating that moisture rather than heating the air But when the soil is already dry all that energy goes straight into making the air hotter explained coauthor Prof Arpita Mondal Associate Professor at IIT BombayThe experts urged the need to understand these mechanisms to improve the ability to forecast and prepare for extreme heat events in South Asia It will also enable better prediction and mitigation of the impacts of future heatwavesThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoeveratOptionskeyd0ddb8ef8f1a62a8cdd22fac27fc5ea7formatiframeheight90width728params