Long-term changes in the within-season temporal profile of southwest monsoon over western India
This paper presents results of a study of long term trends in the characteristics of the within-season temporal profile of southwest monsoon rainfall over western India during the last five decades in relation to global warming induced regional climate change. In contrast to recent climate change analyses and projections, no significant long-term trends have been observed in this study. Slow decadal scale variations observed are analysed in relation to Pacific Decadal Oscillations (PDO). Daily variations in rainfall anomaly show opposite characteristics during negative and positive phases of PDO. The above-normal rainfall (>25%) is found during the starting phase of monsoon in negative PDO. Over the last decade, i.e., during 2000–2007, the seasonal rainfall amount, as well as seasonal span of southwest monsoon over western India is indicative of a gradual increase.
KeywordsSouthwest monsoon decadal climate variability Pacific decadal oscillations.
PDO data are obtained from Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of Washington, USA. Funding for the study is provided by Ministry of Earth Sciences (MoES), Govt. of India under the Indo–UK Changing Water Cycle Programme (MoES/ NERC/16/02/10 PC-II). We are thankful to the reviewers and the editor for their suggestions.
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