Chlorophyll Variability in the Bay of Bengal and its Relation with ENSO

Abstract

The concentration of chlorophyll-a (Chl-a) is influenced by the impact of El-Nino southern oscillation in Bay of Bengal sea water. In this study using data, monthly mean chlorophyll data derived from the sea-viewing Wild of view-sensor, the sea surface temperature is derived from the National Oceanic and Atmospheric Administration Advanced Very High-Resolution Radiometer, satellite derived monthly wind data is derived from the using CCMP, satellite altimeter sea surface height anomaly data derived from the TOPEX and the monthly mean mixed layer depth is taken from the Argo gridded data. The study period in this study is 1980-2017 (January-December) were analyzed the provincial nature of the ENSO linked with the above parameters. This satellite derived ocean data was used to identify the variability of the chlorophyll-a in Bay of Bengal associated with the ENSO. The witness of the Bay of Bengal is varied and response of climate modes due to El-Nino southern oscillation. These changing climate models have been impacting and influence the chlorophyll productivity in Bay of Bengal waters. Keeping in this view this study attempts to analyze the chlorophyll activity during the strong El-Nino years (1993, 1988, 1992, 1998, 2010, 2016) and strong La-Nina years (1989, 1999, 2000, 2008) in Bay of Bengal. In this study we must choose six provinces and observed that the variability and response of chlorophyll variability in Bay of Bengal during with peak El-Nino years (2010&2016) and La-Nina years (2008&2011) in Bay of Bengal. The relation between sea surface temperature and Chl-a indicates that, during peak El-Nino years the low Chl-a concentration were observed due to down-welling process. The high Chl-a concentration (0.15mg/m 3 ) were observed during peak La-Nina years in Bay of Bengal. The variability of the chlorophyll concentration is used to understand and improve the climate mode at different provinces in Bay of Bengal during ENSO time.