Radiative heat exchange in a tropical Chwaka bay, east coast of Zanzibar

Abstract

Radiative heat fluxes were measured from a platform during the period 18 January through 9 February 1996. Cloud cover ranged from clear skies to overcast while the air temperature was near 28^oC. Sea surface temperature varied between 27 and 34^oC and air vapour pressure from 26 to 39 mb. Measured values of both short-wave and net long-wave radiative fluxes were compared with those computed from empirical formulas. The net long wave radiative fluxes were obtained by taking the difference between simultaneous measurements of net all-wave and net solar heat fluxes. The agreement between

the observations and the formulas varied between 1 to 20% for short-wave radiation and from 0.3 to 15% for long-wave radiation. The formulas by Reed (1977) and Budyko (1963) have been found to be the most appropriate for estimating the two fluxes, respectively. It is concluded that the empirical formulas, used for Chwaka bay, gives results that are similar to those obtained elsewhere.