Heat Balance of the Red Sea

Abstract

The Red Sea is one of the few regions of the world where the balance of the surface heat fluxes at the air–sea interface can be compared favourably with the advective heat flux at Bab-al-Mandab. Various estimates of the surface heat fluxes and advective oceanic heat flux are discussed and their average values are derived. The annual average values for the absorbed solar radiation at the sea surface, net long-wave radiation, latent heat and sensible heat fluxes are, respectively, 220 ± 6, 70 ± 5, 165 ± 4 and −3 W m−2 for the Red Sea as a whole. This gives a heat loss of −12 W m−2 at the air–sea interface which is almost in agreement with the net advective flux of 13 ± 4 W m−2 to the Red Sea at Bab-al-Mandab. Because of its location in an arid area, the evaporation is high and precipitation is very low. The average precipitation along the eastern side of the Red Sea is about 0.05 m per year. The estimates of evaporation vary in time and space, and the average is about 2 m per year for the whole Red Sea. Based on the Comprehensive Ocean Atmospheric Data Set (COADS) from 2000 to 2010, the monthly averages of latent heat flux are calculated for the southern, central and northern regions of the Red Sea. The variability of the net long-wave radiation and sensible heat flux for these regions is also shown. The surface heat fluxes over the Red Sea show a wide temporal and spatial variation.