气候变化领域集成服务门户(CCPortal): Potential evaporation at eddy-covariance sites across the globe

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DOI	10.5194/hess-23-925-2019
	Potential evaporation at eddy-covariance sites across the globe
	Maes W.H.; Gentine P.; Verhoest N.E.C.; Miralles D.G.
发表日期	2019
ISSN	1027-5606
起始页码	925
结束页码	948
卷号	23 期号:2
英文摘要	Potential evaporation (Ep) is a crucial variable for hydrological forecasting and drought monitoring. However, multiple interpretations of Ep exist, which reflect a diverse range of methods to calculate it. A comparison of the performance of these methods against field observations in different global ecosystems is urgently needed. In this study, potential evaporation was defined as the rate of terrestrial evaporation (or evapotranspiration) that the actual ecosystem would attain if it were to evaporate at maximal rate for the given atmospheric conditions. We use eddy-covariance measurements from the FLUXNET2015 database, covering 11 different biomes, to parameterise and inter-compare the most widely used Ep methods and to uncover their relative performance. For each of the 107 sites, we isolate days for which ecosystems can be considered unstressed, based on both an energy balance and a soil water content approach. Evaporation measurements during these days are used as reference to calibrate and validate the different methods to estimate Ep. Our results indicate that a simple radiation-driven method, calibrated per biome, consistently performs best against in situ measurements (mean correlation of 0.93; unbiased RMSE of 0.56 mm dayĝ'1; and bias of ĝ'0.02 mm dayĝ'1). A Priestley and Taylor method, calibrated per biome, performed just slightly worse, yet substantially and consistently better than more complex Penman-based, Penman-Monteith-based or temperature-driven approaches. We show that the poor performance of Penman-Monteith-based approaches largely relates to the fact that the unstressed stomatal conductance cannot be assumed to be constant in time at the ecosystem scale. On the contrary, the biome-specific parameters required by simpler radiation-driven methods are relatively constant in time and per biome type. This makes these methods a robust way to estimate Ep and a suitable tool to investigate the impact of water use and demand, drought severity and biome productivity. © Author(s) 2019.
语种	英语
scopus关键词	Drought; Evaporation; Evapotranspiration; Soil moisture; Water supply; Atmospheric conditions; Eddy covariance measurements; Hydrological forecasting; In-situ measurement; Multiple interpretations; Potential evaporation; Relative performance; Stomatal conductance; Ecosystems; biome; drought; eddy covariance; energy balance; evaporation; global perspective; soil water; stomatal conductance; terrestrial ecosystem
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159757
作者单位	Maes, W.H., Laboratory of Hydrology and Water Management, Ghent University, Coupure Links 653, Gent, 9000, Belgium; Gentine, P., Department of Earth and Environmental Engineering, Columbia University, New York City, NY 10027, United States; Verhoest, N.E.C., Laboratory of Hydrology and Water Management, Ghent University, Coupure Links 653, Gent, 9000, Belgium; Miralles, D.G., Laboratory of Hydrology and Water Management, Ghent University, Coupure Links 653, Gent, 9000, Belgium
推荐引用方式 GB/T 7714	Maes W.H.,Gentine P.,Verhoest N.E.C.,et al. Potential evaporation at eddy-covariance sites across the globe[J],2019,23(2).
APA	Maes W.H.,Gentine P.,Verhoest N.E.C.,&Miralles D.G..(2019).Potential evaporation at eddy-covariance sites across the globe.Hydrology and Earth System Sciences,23(2).
MLA	Maes W.H.,et al."Potential evaporation at eddy-covariance sites across the globe".Hydrology and Earth System Sciences 23.2(2019).