Abstract:
Radiative fluxes and surface energy fluxes computed using the eddy covariance method from
January to December 2013 were used to investigate the partition of energy and energy exchange
over degraded grassland in the Sudanian savannah region of West Africa. In Sumbrungu Agunsi,
(10.841°N, 0.918°W), in Ghana’s upper east area, an Eddy Covariance station was erected near
to the Ghana–Burkina-Faso border. The fluctuations in radiation components, energy fluxes, and
surface characteristics components were studied on a seasonal and daily basis. The Incoming
shortwave radiation, out-going shortwave radiation, incoming long wave radiation and out-going
long wave radiation all varied annually, resulting in a seasonal variation in net radiation. The
soil moisture content, evaporative fraction, and the surface albedo were found to be low during
the dry season but high during the wet season, while, the Bowen ratio was found to be high
during the dry season but low during the wet season. During the wet season, majority of the
available energy were converted to latent heat, but, during the dry season, majority of the
available energy was transformed to sensible heat. The station’s energy balance closure was
investigated; slope of the regression found was 0.67 with an intercept of 33 Wm-2
. The reasons
for the station’s energy balance not being closed were investigated.
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