Long-term changes in the within-season temporal profile of southwest monsoon over western India
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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.
- Anderson G C and Nash D J 2013 Long-term variability in the date of monsoon onset over western India; Clim. Dyn. 40 2589–2603.Google Scholar
- Ghosh S, Lunia V and Gupta A 2009 Trend analysis of Indian summer monsoon rainfall at different spatial scales; Atmos. Sci. Lett. 10 285–290.Google Scholar
- Jagannathan P and Bhalme H N 1973 Changes in the pattern of distribution of southwest monsoon rainfall over India associated with sunspots; Mon. Wea. Rev. 101 694–700.Google Scholar
- Krishna Kumar K, Patwardhan S K, Kulkarni A, Kamala K, Rao Koteswara K and Jones R 2011 Simulated projections for summer monsoon climate over India by a high-resolution regional climate model (PRECIS); Curr. Sci. 101 (3) 312–326.Google Scholar
- Rajeevan M, Bhate J, Kale J D and Lal B 2006 High resolution daily girded rainfall data for the Indian region: Analysis of break and active monsoon spells; Curr. Sci. 91 (3) 296–306.Google Scholar
- Satyanarayana P and Srinivas V V 2008 Regional frequency analysis of precipitation using large-scale atmospheric variables; J. Geophys. Res. 13 (D24110). doi: 10.1029/2008JD010412.
- Tyagi A, Mazumdar A B, Khole M, Gaonkar S B and Devi S 2011 Re-determination of normal dates of onset of southwest monsoon over India; Mausam 62 321–328.Google Scholar
- Yadav R K 2016 On the relationship between Iran surface temperature and north-west India summer monsoon rainfall; Int. J. Clim., doi: http://dx.doi.org/10.1002/joc.4648.