An oceanic eddy of size about 150 kilometer diameter observed in the northeastern Arabian Sea using remote sensing satellite sensors; IRS-P4 OCM, NOAA-AVHRR and NASA Quickscat Scatterometer data. The eddy was detected in the 2nd week of February in Indian Remote Sensing satellite (IRS-P4) Ocean Color Monitor (OCM) sensor retrieved chlorophyll image on 10th February 2002, between latitude 16°90′–18°50′N and longitude 66°05′–67°60′E. The chlorophyll concentration was higher in the central part of eddy (~1.5？mg/m3) than the peripheral water (~0.8？mg/m3). The eddy lasted till 10th March 2002. NOAA-AVHRR sea surface temperature (SST) images generated during 15th February-15th March 2002. The SST in the eddy’s center (~23°C) was lesser than the surrounding water (~24.5°C). The eddy was of cold core type with the warmer water in periphery. Quickscat Scatterometer retrieved wind speed was 8–10？m/sec. The eddy movement observed southeast to southwest direction and might helped in churning. The eddy seemed evident due to convective processes in water column. The processes like detrainment and entrainment play role in bringing up the cooler water and the bottom nutrient to surface and hence the algal blooming. This type of cold core/anti-cyclonic eddy is likely to occur during late winter/spring as a result of the prevailing climatic conditions. 1. Introduction Eddies are small features with a big impact. They are where a lot of ocean physics happen and are an integral part of our climate system. Coastal eddies have a major role in regulating the weather near the shore and they are important for fisheries. In the open ocean, eddies bring nutrient-rich cold water up to the surface and are an important part of the global carbon cycle [1]. These eddies are rotating masses of water that have broken off from a strong front. Eddies are crucial to the transport of heat, momentum, trace chemicals, biological communities, the oxygen, and nutrients relating to life in the sea [2]. They are also active in air-sea interaction, both through response to weather and in shaping the patterns of warmth that drives the entire atmospheric circulation. Measurements of ocean color and the fate of light in the ocean are extremely useful for describing biological dynamics in surface waters [3–5]; thus the oceanographic communities has made a substantial commitment to remote sensing of ocean color from space [6, 7]. Regional scale ocean color imageries are particularly useful for space-borne studies of ocean margins because of the importance and dominance of mesoscale features (upwelling
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