Impact on the chlorophyll concentration in the Bay of Bengal and Arabian Sea during Indian Ocean dipole mode
The chlorophyll Chl concentration in the seawater of the Bay of Bengal BoB and the Arabian Sea AS changes most during the Indian Ocean dipole IOD mode event. The empirical orthogonal function EOF of several oceanographic and atmospheric data was studied, using 9 years 1998–2006 of reanalysed satellite data. The variation of Chl during the period of September to November SON over the 9 years has been studied in this article. It has been found that significant enhancement of Chl in the BoB takes place during IOD years owing to the surface wind action, that is, wind-stress curl WC, which favours the upwelling process, whereas the AS shows a decline in concentration of Chl owing to a reduced open ocean upwelling process.