Eddy Covariance Measurements of Turbulent Heat Fluxes over a Grass-covered Surface in a Tropical Location

Omodara E. Obisesan *

Department of Physics, Anchor University, Lagos, Nigeria.

Oladimeji A. Babatunde

Department of Physics, Mountain Top University, Ogun, Nigeria.

Opeyemi R. Omokungbe

Olusegun Agagu University of Science and Technology, Ondo, Nigeria.

Ayodele P. Olufemi

Department of Physics, University of Medical Sciences, Ondo, Nigeria.

*Author to whom correspondence should be addressed.


Abstract

In this study, an Eddy Covariance (EC) system was deployed to measure the turbulent heat fluxes (sensible and latent heat fluxes) at a farmland located at Obafemi Awolowo University, Ile-Ife, Nigeria. The period of measurement was between 2016 and 2019. The surface of the measurement area was covered by grass (Axonopus fissifolius) and changes from leafy-green during the wet season to dry twigs during the dry season. The sensible heat flux, Hs obtained ranged between -0.8 and 181.9 Wm-2 while the latent heat flux, Hl varied between 0.9 and 218.0 Wm-2. The maximum daytime value of Hs peaked in January while the maximum daytime value of Hl peaked in October. The sensible heat flux was 59 % higher than the latent heat flux during the Harmattan months (January, February and December), while the latent heat flux was 63 % higher than the sensible heat flux during the wet months (April - November). The study concluded that 91 % of the energy available at the surface during the period of study, was used for evapotranspiration while only 9 % was used for sensible heating as shown by the distribution of the Bowen ratio.

Keywords: Eddy covariance, turbulent heat fluxes, sensible heat flux, latent heat flux


How to Cite

Obisesan , O. E., Babatunde , O. A., Omokungbe , O. R., & Olufemi , A. P. (2023). Eddy Covariance Measurements of Turbulent Heat Fluxes over a Grass-covered Surface in a Tropical Location. International Journal of Environment and Climate Change, 13(8), 604–616. https://doi.org/10.9734/ijecc/2023/v13i81989

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