Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/21/2001
Publication Date: 10/21/2001
Technical Abstract: The radiation balance is fundamental in determining the energy and water balance of any surface. Objectives were to compare measured albedo with a previously published grass albedo model and to evaluate net radiation determined from the individual component measurements with a four component net radiometer and a miniature net radiometer. We measured incident short-wave (SW) radiation, reflected short-wave radiation, incident long- wave (LW) radiation, and emitted LW radiation with an albedometer (CM 14), paired pyrgeometers (PIR), a net pyrgeometer (CG 2), and a four-component net radiometer (CNR 1) along with a miniature domed net radiometer (REBS 7.1) over irrigated, mowed tall fescue (Festuca arundinacea Schreb.) turf grass at Bushland, TX, during the summer of 2001. Albedo near solar noon was 0.18ñ0.03 with the mean daytime albedo being 0.227. The modeled albedo was similar to the post solar noon data but over estimated the pre solar noon data. The CNR 1 measured the net SW radiation balance well, but it was less precise in measuring the net LW balance compared with the CG 2 or the paired PIR pyrgeometers. Net radiation measured with the REBS radiometer was strongly correlated with the sum of the CM 14 and CG 2 measurements and with the combined CM 14 and paired PIR measurements, but the CNR 1 correlations had more scatter than the REBS with either the PIR or CG 2 pyrgeometers summed with the CM 14 albedometer.