Wind-driven cross-equatorial flow in the Indian Ocean

Abstract

Meridional velocity, mass, and heat transport in the equatorial oceans are difficult to estimatebecause of the nonapplicability of the geostrophic balance. For this purpose a steady-state model is utilized in the equatorial Indian Ocean using NCEP wind stress and temperature and salinity data fromthe World Ocean Atlas 2005 (WOA05) and Argo. The results show a Somali Current flowing to the south during the winter monsoon carrying -11.5 ± 1.3 Sv (1 Sv [106 m3 s-1) and -12.3 ± 0.3 Sv from WOA05 and Argo, respectively. In the summer monsoon the SomaliCurrent reverses to the north transporting 16.8 ± 1.2 Sv and 19.8 ± 0.6 Sv in the WOA05and Argo results. Transitional periods are considered together and in consequence, there is not a clear Somali Current present in this period. Model results fitwith in situ measurements made around the region, although Argo data results are quite more realisticthan WOA05 data results. © 2012 American Meteorological Society.