Journal of the Marine Biological Association of India

Volume 14 Issue 1

Upsloping of isotherms on the continental shelf off Goa and Bombay in June 1967.

Karl Banse

Bathythermograph sections made in June 1967 in the north eastern Arabian Sea on and near the continental shelf west of Goa, and west and northwest of Bombay, showed a rise of isotherms below the mixed layer, over the levels observed in May in other years. This was especially so in the southern and central part of the area; near Bombay, 35 km from shore, temperatures of 26°C were met at 40 m. However, the very shallow depth reached regularly by much cooler water from July through November had not nearly been attained. It is concluded that seasonal upsloping begins off Goa always before June. It is argued that it is likely to be the case off Bombay too, but the few available observations do not support this. Marked raise of isopycnals towards the coast before the arrival of the southwest monsoon can be expected off Veraval. A trough of the thermocline, approximately 20 m deep in 1967, is a regular feature during the pre-monsoonal months on the outer shelf west and northwest of Bombay

Date : 30-06-1972