Abstract
The Indian summer monsoon season of 2014 was erratic and ended up with a seasonal rainfall deficit of 12 % and a record drought in June. In this study we analyze the moisture transport characteristics for the monsoon season of 2014 using both NCEP FNL reanalysis (FNL) and CFSv2 (CFS) model data. In FNL, in June 2014 there was a large area of divergence of moisture flux. In other months also there was lesser flux. This probably is the cause of 2014 drought. The CFS model overestimated the drought and it reproduces poorly the observed rainfall over central India (65E–95E; 5N–35N). The correlation coefficient (CC) between the IMD observed rainfall and CFS model rainfall is only 0.1 while the CC between rainfall and moisture flux convergence in CFS model is only 0.20 and with FNL data −0.78. This clearly shows that the CFS model has serious difficulty in reproducing the moisture flux convergence and rainfall. We found that the rainfall variations are strongly related to the moisture convergence or divergence. The hypothesis of Krishnamurti et al. (J Atmos Sci 67:3423–3441, 2010) namely the intrusion of west African desert air and the associated low convective available potential energy inhibiting convection and rainfall shows some promise to explain dry spells in Indian summer monsoon. However, the rainfall or lack of it is mainly explained by convergence or divergence of moisture flux. © 2016 Springer-Verlag Berlin Heidelberg
Original language | English (US) |
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Pages (from-to) | 297-312 |
Number of pages | 16 |
Journal | Climate Dynamics |
Volume | 49 |
Issue number | 1-2 |
DOIs | |
State | Published - Sep 16 2016 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: The entire work has been done with the support of the Indian Institute of Tropical Meteorology (IITM), Pune, fully funded by the Ministry of Earth Sciences (MoES), New Delhi, Govt. of India (Ref. No. MM/SERP/Andhra-Univ/2013/IND-4/002/1307). Figures 1 and 2 are used from the IMD published reports. Plots in this work are made using the GrADS and Origin software which are freely available online. Thanks are due to the two reviewers for their insightful comments.