Affiliation:
1. Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan
2. Department of Water Resources Engineering, Chulalongkorn University, Bangkok 10330, Thailand
Abstract
Ground heat flux may play an important role in surface energy balance. In this study we evaluate the performance of the objective hysteresis model (OHM) for estimating ground heat flux from net radiation and compare it with the linear regression model. The experimental sites include residential roofs (concrete), campus grassland, agricultural grassland, and peat bog. Our field measurements show that the mean partition coefficient from net radiation to ground heat flux varied from 0.47 (concrete roof) to 0.079 (agricultural grassland). The mean hysteresis (lag) factors for residential roof, campus grassland, and peat bog were 0.55, 0.26, and −0.11 h, respectively; and the hysteresis factor at the agricultural site was only 0.032 h. However, the partition and hysteresis coefficients in the OHM were found to vary with time for the same surface. Our measurements and analysis show that when the hysteresis factor is larger than 0.11 h, ground heat flux estimates from net radiation can be improved (17–37% reduction in the root mean square error) by using OHM instead of a simple linear regression model.
Funder
Ministry of Science and Technology, Taiwan
Core Research Project, National Taiwan University
Subject
Atmospheric Science,Environmental Science (miscellaneous)
Reference41 articles.
1. Efficient prediction of ground surface temperature and moisture, with inclusion of a layer of vegetation;Deardorff;J. Geophys. Res.,1978
2. Allen, R.G., Pereira, L.S., Raes, D., and Smith, M. (1998). Crop Evapotranspiration-Guidelines for Computing Crop Water Requirements, FAO. FAO Irrigation and Drainage Paper 56.
3. EWRI (2004, March 29). The ASCE Standardized Reference Evapotranspiration Equation. Available online: http://www.kimberly.uidaho.edu/water/asceewri/.
4. Parameterization of subsurface heating for soil and concrete using net radiation data;Doll;Bound.-Layer Meteorol.,1985
5. Local-scale urban meteorological parameterization scheme (LUMPS): Longwave radiation parameterization and seasonality-related developments;Loridan;J. Appl. Meteorol. Climatol.,2011