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The Andaman coral reef region experienced mass bleaching events during 1998 and 2010. The purpose of this study is to investigate the role of the El Niño in the coral reef bleaching events of the Andaman region. Both Niño 3.4 and 3 indices were examined to find out the relationship between the mass bleaching events and El Niño, and correlated with sea surface temperature (SST) anomalies in the Andaman Sea. The result shows that abnormal warming and mass bleaching events in the Andaman Sea were seen only during strong El Niño years of 1997-1998 and 2009-2010. The Andaman Sea SST was more elevated and associated with El Niño Modoki (central Pacific El Niño) than conventional El Niño (eastern Pacific El Niño) occurrences. It is suggested that the development of hot spot patterns around the Andaman Islands during May 1998 and April-May 2010 may be attributed to zonal shifts in the Walker circulation driven by El Niño during the corresponding period.

This paper explains about the implementation of a real-time data transmission scheme for coastal data buoy system using Global System for Mobile Communication (GSM). The General Packet Radio Service (GPRS) technology is utilised to handle huge volume of data through low power, higher transmission rate and cost effective means. In conventional buoy system with satellite telemetry using INMARSAT and INSAT, the high resolution raw data collected are not transmitted in real time and only stored due to constrains in the transmission schemes. In this buoy system the stored data would be transmitted through GPRS modem and received through FTP in real time.

Based on the in-situ subsurface thermal and salinity measurements from the Ocean Moored Buoy Network for Northern Indian Ocean (OMNI) during the passage of very severe tropical cyclones (TCs) in the Bay of Bengal, we have identified that the depth of ocean‐atmosphere interaction is limited by the depth of the pycnocline. During the TC Vardha and Phailin with cyclone-period-averaged wind speeds of 8 and 21 m/s, respectively, the maximum possible rates of water-vapor generation during the cyclone period, computed based on the salinity changes and considering precipitation, are 1.0 and 9.3 kg/m2/h, respectively. For the same wind speeds, based on the ocean heat content (OHC) changes, it is quantified that ~78% and 89% of the OHC changes are in the form of latent heat. The real-time availability of the in-situ subsurface parameters can be used in the ocean-atmosphere coupled models and intensification studies.

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