PRELIMINARY RESULTS FROM WOCE HYDROGRAPHIC SECTIONS AT 80-DEGREES-E AND 32-DEGREES-S IN THE CENTRAL INDIAN OCEAN

摘要

The hydrographic properties and circulation along sections at 80 degrees E and 32 degrees S in March, 1995, in the Indian Ocean are described very briefly. A halocline was well-developed in the tropics. A westward coastal jet of fresh Bay of Bengal water was present at the sea surface at Sri Lanka with eastward flow of saline Arabian Sea water below. The Equatorial Undercurrent was well developed as were the deep equatorial jets. The Indonesian throughflow jet presented a large dynamic signature at 10 to 14 degrees S coinciding with a strong front in all properties to great depth. Its mid-depth salinity minimum is separated from that of the Antarctic Intermediate Water. The Subantarctic Mode Water of the southeastern Indian Ocean imparts its high oxygen ventilation signature to the whole of the transects, including the tropical portion. The deepest water in the Central Indian Basin is pooled in the center of the basin, and its principal source appears to be the sill at 11 degrees S through the Ninetyeast Ridge. Northward deep water transports across the 32 degrees S section were similar to those observed in 1987 but the deep water was lower in oxygen and fresher than in 1987. Upper ocean waters at 32 degrees S were more saline and warmer in 1995. [References: 11]