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arXiv · 2011.11372

A short perspective on the Mascarene High and the abnormal Indian Monsoon during 2015

R. Krishnan·Bhupendra Singh·R. Vellore·M. Mujumdar·P. Swapna·Ayantika Choudhury·Manmeet Singh·B. Preethi·M. Rajeevan
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Abstract

The initiation of the Indian summer monsoon circulation during late May / early June arises through large-scale land-sea thermal contrast and setting up of negative pressure gradient between the Monsoon Trough over the Indo-Gangetic plains and the Mascarene High over the subtropical Indian Ocean. The meridional pressure gradient together with the Earth's rotation (Coriolis force) creates the summer monsoon cross-equatorial flow, while feedbacks between moisture-laden winds and latent heat release from precipitating systems maintain the monsoon circulation during the June-September (JJAS) rainy season (Krishnamurti and Surgi, 1987). This simplified view of the Indian monsoon is a useful starting point to draw insights into the variability of the large-scale monsoon circulation.

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R. Krishnan, Bhupendra Singh, R. Vellore, M. Mujumdar, P. Swapna, Ayantika Choudhury, Manmeet Singh, B. Preethi, M. Rajeevan. 2020-11-23. A short perspective on the Mascarene High and the abnormal Indian Monsoon during 2015. https://arxiv.org/abs/2011.11372

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