The first observational experiment under the Indian Climate Research Programme, called the Bay of Bengal Monsoon Experiment (BOBMEX), was carried out during July-August 1999. BOBMEX was aimed at measurements of important variables of the atmosphere, ocean, and their interface to gain deeper insight into some of the processes that govern the variability of organized convection over the bay. Simultaneous time series observations were carried out in the northern and southern Bay of Bengal from ships and moored buoys. About 80 scientists from 15 different institutions in India collaborated during BOBMEX to make observations in most-hostile conditions of the raging monsoon. In this paper, the objectives and the design of BOBMEX are described and some initial results presented. During the BOBMEX field phase there were several active spells of convection over the bay, separated by weak spells. Observation with high-resolution radiosondes, launched for the first time over the northern bay, showed that the magnitudes of the convective available potential energy (CAPE) and the convective inhibition energy were comparable to those for the atmosphere over the west Pacific warm pool. CAPE decreased by 2-3 kJ kg-1 following con-vection, and recovered in a time period of 1-2 days. The surface wind speed was generally higher than 8 ms-1. The thermohaline structure as well as its time evolution during the BOBMEX field phase were found to be different in the northern bay than in the southern bay. Over both the regions, the SST decreased during rain events and increased in cloud-free conditions. Over the season as a whole, the upper-layer salinity decreased for the north bay and increased for the south bay. The variation in SST during 1999 was found to be of smaller amplitude than in 1998. Further analysis of the surface fluxes and currents is expected to give insight into the nature of coupling.

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Spaceborne sensors have limited capability to acquire images with wider swath at high spatial and high temporal resolutions simultaneously. This study reports a ground processing technique that combines images from two sensors onboard Resourcesat-2 (RS2) Linear Imaging and Self-Scanning Sensor (LISS III) and an Advanced WideField Sensor (AWiFS) to overcome this limitation. The spatial resolution of LISS III is 23.5 × 23.5m and that of AWiFS is 56 × 56m. The temporal resolution of LISS III is 24 days and that of AWiFS is 5 days. The 140-km swath of the LISS III overlaps at center portion of 740-km swath of AWiFS in simultaneous acquisition. Assume that the nonoverlapping region of the AWiFS contains similar Earth's surface features of the LISS III overlapping region; then, it is possible to enhance the spatial resolution of AWiFS to the spatial resolution of LISS III in the nonoverlapping region. With this assumption, we propose a novel technique to enhance the spatial resolution of the nonoverlapping region through a single-image super-resolution technique using nonsubsampled contourlet transform (NSCT) and evaluated it on RS2 data-sets. The proposed method can create a synthetic image with 740-km swath at 23.5 × 23.5m spatial and 5-day temporal resolutions. Experimental results demonstrated that it outperforms the support vector regression (SVR)-based methods in prediction accuracy and computational time.

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