%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Roxy, M. K.
%A Ritika, K.
%A Terray, Pascal
%A Murtugudde, R.
%A Ashok, K.
%A Goswami, B. N.
%T Drying of Indian subcontinent by rapid Indian Ocean warming and a weakening land-sea thermal gradient
%D 2015
%L fdi:010065146
%G ENG
%J Nature Communications
%@ 2041-1723
%K INDE ; OCEAN INDIEN
%M ISI:000357176400003
%P art. 7423 [10 ]
%R 10.1038/ncomms8423
%U https://www.documentation.ird.fr/hor/fdi:010065146
%> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-10/010065146.pdf
%V 6
%W Horizon (IRD)
%X There are large uncertainties looming over the status and fate of the South Asian summer monsoon, with several studies debating whether the monsoon is weakening or strengthening in a changing climate. Our analysis using multiple observed datasets demonstrates a significant weakening trend in summer rainfall during 1901-2012 over the central-east and northern regions of India, along the Ganges-Brahmaputra-Meghna basins and the Himalayan foothills, where agriculture is still largely rain-fed. Earlier studies have suggested an increase in moisture availability and land-sea thermal gradient in the tropics due to anthropogenic warming, favouring an increase in tropical rainfall. Here we show that the land-sea thermal gradient over South Asia has been decreasing, due to rapid warming in the Indian Ocean and a relatively subdued warming over the subcontinent. Using long-term observations and coupled model experiments, we provide compelling evidence that the enhanced Indian Ocean warming potentially weakens the land-sea thermal contrast, dampens the summer monsoon Hadley circulation, and thereby reduces the rainfall over parts of South Asia.
%$ 032 ; 021