Abstract
Direct measurements of sensible heat fluxes were conducted over a grass surface at Ladner, British Columbia, using yaw-sphere-thermometer eddy-correlation systems. The results show that for half-hour averaging periods, there is no phase-lag between sensible heat and net radiation flux densities. Field comparison of two yaw-sphere-thermometer systems gave good and consistent agreement. At a height of 2 m above ground and a horizontal crosswind separation of 1.5 m, less than 5% variability was noted in the measured heat fluxes. For a 19-m horizontal separation, the variability was less than 20%. The aridity index (α) advanced by Priestley and Taylor (1972), is shown to be a potentially useful climatic indicator.
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Yap, D., Oke, T.R. Eddy-correlation measurements of sensible heat fluxes over a grass surface. Boundary-Layer Meteorol 7, 151–163 (1974). https://doi.org/10.1007/BF00227910
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DOI: https://doi.org/10.1007/BF00227910