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The Northern Indian Ocean (NIO) is unique due to seasonal reversal of wind patterns, the formation of vortices and eddies which make satellite observations arduous. The veracity of sea surface wind (SSW) and sea surface temperature (SST) products of sun-synchronous AMSR-2 satellite are compared with high-temporal moored buoy observations over the NIO. The two year-long (2013-2014) comparisons reveal that the root-mean-square-error (RMSE) of AMSR-2 SST and SSW is <0.4 • C and <1.5 ms −1 , respectively, which are within the error range prescribed for the AMSR-2 satellite (±0.8 • C, ±1.5 ms −1). The SST-wind relation is analyzed using data both from the buoy and satellite. As a result, the low-SST is associated with low-wind condition (positive slope) in the northern part of the Bay of Bengal (BoB), while low SST values are associated with high wind conditions (negative slope) over the southern BoB. Moreover, the AMSR-2 displayed larger slope for SST-wind relation and could be mainly due to overestimation of SST and underestimation of wind as compared to the buoy. The AMSR-2 SSW exhibited higher error during post-monsoon followed by monsoon season and could be attributed to the high wind conditions associated with intense oceanic vortices. The study suggests that the AMSR-2 products are reliable and can be used in tropical air-sea interactions, meso-scale features, and weather and climate studies.

Equipment and structures deployed in seawater and other marine environments are susceptible to marine growth. This marine biofouling is one of the critical factors that affects the measurement of continuous real-time data from the oceanographic sensors deployed for long-term observations. To understand the characteristics of biofouling on marine sensors, an investigation was conducted on sensors deployed in a moored buoy network deployed and maintained by the National Institute of Ocean Technology (NIOT) in the Arabian Sea and Bay of Bengal regions. The present paper attempts to elucidate the characteristics of biofouling on sensor components deployed at seven locations in the Bay of Bengal and five locations in the Arabian Sea, at varying depths ranging from the surface to 500-m depth. Biofouling on bare sensor surfaces and surfaces with various antifouling measures has been studied for 2 consecutive years (2015 and 2016), and the effect of antifouling measures is discussed in this paper. Among the locations studied, buoys deployed in the Arabian Sea exhibited a higher biofouling load compared to the buoys deployed in the Bay of Bengal. The study showed that the pedunculate barnacles Lepas anatifera Linnaeus, 1758, was the predominant biofouling species on these sensors. Furthermore, observations show that the use of copper- and zinc-based antifouling methods reduced the incidence of biofouling by 59% on average.

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