Summary
The diurnal variations of net radiation have been studied by analysing one year data measured at a tropical station, Osu (7.43° N, 4.58° E), in Nigeria. The maximum net daytime flux (which occurs around 14h local time) varies in the course of the year from 382.6±136.7Wm−2 in the wet season (April–October) to 480.3±61.8 Wm−2 in the dry season (November–March). The low values (and large fluctuations) of the hourly means recorded during the wet (monsoon) season are attributed to the important roles that the convective clouds and water vapour play in the atmospheric radiation budget, which is very pronounced in the tropical areas of West Africa.
The daily amplitude of the net radiation is larger for the dry season (maximum in November) than it is for the wet season (minimum in July). A lag of about 2 hours is observed between the times when the maxima of the air temperature and the net radiation courses occur over the area.
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On leave from the Department of Physics, Obafemi Awolowo University, Ile-Ife, Nigeria.
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Jegede, O.O. Diurnal variations of net radiation at a tropical station — Osu; Nigeria. Theor Appl Climatol 58, 161–168 (1997). https://doi.org/10.1007/BF00865016
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DOI: https://doi.org/10.1007/BF00865016