Surface heat flux estimation with wind-profiler/RASS and radiosonde observations

A bulk ABL similarity approach was used to make regional estimates of the s ensible heat flux by combining surface temperature measurements with mixed layer temperature and wind speed profiles. The mixed layer profiles were me asured by a 915 MHz Profiler/Radio Acoustic Sounding System and by radioson des in north-central Oklahoma at the ARM Southern Great Plains CART Central Facility. A comparison of calculated sensible heat flux values with region al mean values measured at two ground stations showed good agreement with r = 0.88 and r = 0.76 for the 915 MHz profiler and the radiosonde data sets, respectively. Estimates of friction velocity u, by means of radiosonde win d profiles gave good results when compared to values measured by an surface eddy correlation system with a correlation coefficient r = 0.77. However, u, values obtained from wind profiles measured by the 915 MHz profiler were underestimated, because these velocity measurements were systematically to o small. The results also show that the 915 MHz Profiler/Radio Acoustic Sou nding System is capable of providing the needed temperature measurements to make reasonable regional estimates of sensible heat fur. (C) 2000 Elsevier Science Ltd. All rights reserved.