Atmospheric controls on the precipitation isotopes over the Andaman Islands, Bay of Bengal

• DOI: 10.1038/srep19555
• Publication Date: 2016-01-25T12:02:32Z
• Authors: S. Chakraborty; N. Sinha; R. Chattopadhyay; S. Sengupta; P. M. Mohan; A. Datye
• Keywords: East Asian Monsoon

Abstract Isotopic analysis of precipitation over the Andaman Island, Bay Bengal was carried out for year 2012 and 2013 in order to study atmospheric controls on rainwater isotopic variations. The oxygen hydrogen compositions are typical tropical marine sites but show significant variations depending ocean-atmosphere conditions; maximum depletion observed during cyclones. composition seems be controlled by dynamical nature moisture rather than individual rain events. Precipitation isotopes undergo systematic depletions response organized convection occurring a large area modulated integrated effect convective activities. appear linked with monsoon intraseasonal variability addition synoptic scale fluctuations. During early mid amount arose primarily due re-evaporation later phase it driven convergence evaporation. Amount had distinct characteristics these two years, which appeared monsoon. It is shown that variable limits our ability reconstruct past-monsoon rainfall annual sub-annual time scale.