Surface kinetic temperature mapping using satellite spectral data in Central Main Ethiopian Rift and adjacent highlands

Abstract

Remotely sensed thermal-infrared spectral data can be used to derive surface temperature of any object if the optical and thermal properties are known. In this study TM band six has been used to assess the spatial variability of the kinetic temperature of the central Ethiopian rift lakes and adjacent highlands. NOAA-AVHRR data have been used to understand the relative differences of the monthly lake surface kinetic temperatures. The result revealed that despite the limited topographic differences of the rift lakes and their proximity, the surface kinetic temperature difference is high, mainly due to groundwater and surface water fluxes. From thermal signature analysis two hot springs below the lake bed of Ziway were discovered. The various hot springs around three of the lakes have limited role in the overall water budget of these lakes as compared to the total surface water and cold groundwater fluxes. Temperature from the land surface shows also large variations with altitude and land cover types.

SINET: Ethiopian Journal of Science Vol. 24, No. 1 (June 2001), pp. 51-68




Key words/phrases: Kinetic temperature, rift lakes, spectral data, thematic mapper, thermal infra-red