气候变化领域集成服务门户(CCPortal): Why has catchment evaporation increased in the past 40 years? A data-based study in Austria

CCPortal

DOI	10.5194/hess-22-5143-2018
	Why has catchment evaporation increased in the past 40 years? A data-based study in Austria
	Duethmann D.; Blöschl G.
发表日期	2018
ISSN	1027-5606
起始页码	5143
结束页码	5158
卷号	22 期号:10
英文摘要	Regional evaporation has increased in many parts of the world in the last decades, but the drivers of these increases are widely debated. Part of the difficulty lies in the scarcity of high-quality long-term data on evaporation. In this paper, we analyze changes in catchment evaporation estimated from the water balances of 156 catchments in Austria over the period 1977-2014 and attribute them to changes in atmospheric demand and available energy, vegetation, and precipitation as possible drivers. Trend analyses suggest that evaporation has significantly increased in 60 % of the catchments (p ≤ 0.05) with an average increase of 29±14 mm yr-1 decade-1 (± standard deviation) or 4.9±2.3 % decade-1. Pan evaporation based on 24 stations has, on average, increased by 29±5 mm yr-1 decade-1 or 6.0±1.0 % decade-1. Reference evaporation over the 156 catchments estimated by the Penman-Monteith equation has increased by 18±5 mm yr-1 decade-1 or 2.8±0.7 % decade-1. Of these, 2.1 % are due to increased global radiation and 0.5 % due to increased air temperature according to the Penman-Monteith equation. A satellite-based vegetation index (NDVI) has increased by 0.02±0.01 decade-1 or 3.1±1.1 % decade-1. Estimates of reference evaporation accounting for changes in stomata resistance due to changes in the NDVI indicate that the increase in vegetation activity has led to a similar increase in reference evaporation as changes in the climate parameters. A regression between trends in evaporation and precipitation yields a sensitivity of a 0.22±0.05 mm yr-2 increase in evaporation to a 1 mm yr-2 increase in precipitation. A synthesis of the data analyses suggests that 43±15 % of the observed increase in catchment evaporation may be directly attributed to increased atmospheric demand and available energy, 34±14 % to increased vegetation activity, and 24±5 % to increases in precipitation. © 2018 Author(s).
语种	英语
scopus关键词	Atmospheric radiation; Evaporation; Runoff; Vegetation; Available energy; Climate parameters; Global radiation; Pan evaporation; Penman-Monteith equations; Standard deviation; Vegetation activity; Vegetation index; Catchments
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/159897
作者单位	Duethmann, D., Institute for Hydraulic and Water Resources Engineering, Vienna University of Technology, Karlsplatz 13/223, Vienna, 1040, Austria; Blöschl, G., Institute for Hydraulic and Water Resources Engineering, Vienna University of Technology, Karlsplatz 13/223, Vienna, 1040, Austria
推荐引用方式 GB/T 7714	Duethmann D.,Blöschl G.. Why has catchment evaporation increased in the past 40 years? A data-based study in Austria[J],2018,22(10).
APA	Duethmann D.,&Blöschl G..(2018).Why has catchment evaporation increased in the past 40 years? A data-based study in Austria.Hydrology and Earth System Sciences,22(10).
MLA	Duethmann D.,et al."Why has catchment evaporation increased in the past 40 years? A data-based study in Austria".Hydrology and Earth System Sciences 22.10(2018).