干旱区生态环境知识资源中心(Arid): Sensitivity of discharge projections to potential evapotranspiration estimation in Northern Tunisia

Arid

DOI	10.1007/s10113-020-01615-8
	Sensitivity of discharge projections to potential evapotranspiration estimation in Northern Tunisia
	Dakhlaoui, Hamouda 1,2,3; Seibert, Jan 3,4; Hakala, Kirsti 3,5
通讯作者	Dakhlaoui, Hamouda ; Seibert, Jan
来源期刊	REGIONAL ENVIRONMENTAL CHANGE
ISSN	1436-3798
EISSN	1436-378X
出版年	2020
卷号	20 期号:2
英文摘要	Tunisia has a long history of coping with water scarcity, and the quantification of climate change impacts on runoff is important for future water management. A major requirement for such studies is an estimation of potential evapotranspiration (PET), which is challenging as many regions often lack the observational data needed for physically based PET equations. In this study, different PET estimation approaches were used to study the impact of PET estimation on discharge projections for catchments in Northern Tunisia. Discharge was simulated for five catchments using three rainfall-runoff models (RRMs): HBV, GR4 and IHACRES. A general differential split sample test (GDSST) was used for an RRM robustness evaluation based on subperiods with contrasting climatic conditions for the 1970-2000 period. Three cases with varying PET were considered: (1) daily calculated PET, (2) long-term daily mean PET with the same values for calibration and validation periods (calculated over the calibration period) and (3) long-term daily mean PET varying between calibration and validation periods (calculated over the calibration and validation period separately). Over the historical period, the comparison between cases 1 and 3 showed little impact of reduced PET information on the RRM performance and robustness. The comparison of cases 2 and 3 indicated a limited impact of varying PET between calibration and validation on the RRM results. The impact of varying levels of PET information on hydrological projections was also analysed over two future 30-year periods: mid-term period (2040-2070) and long-term period (2070-2100), with two representative concentration pathway scenarios (RCPs 4.5 and 8.5), by comparing cases 1 and 2. The projected discharge with constant PET (case 2) was generally lower than the projected discharge with variable PET (case 1) but the difference in volume change did not exceed 9% for both the time period and the RCP scenario considered. While PET slightly increased under the different climate change scenarios, actual evapotranspiration (AET) was found to decrease. These opposite trends of PET and AET can be attributed to the projected decrease in precipitation. Overall, our results demonstrate that discharge, in semi-arid regions like Northern Tunisia, is not sensitive to PET estimates since AET is mainly controlled by the availability of soil moisture. This finding is useful for performing studies of climate change impact on hydrological cycles in arid regions, as our study shows that simple PET estimation is a valid approach for such studies.
英文关键词	Rainfall-runoff modelling PET GDSST Hydrological projection EURO-CORDEX Tunisia
类型	Article
语种	英语
国家	Tunisia ; Switzerland ; Sweden ; Australia
开放获取类型	Green Published, hybrid
收录类别	SCI-E ; SSCI
WOS记录号	WOS:000519139500002
WOS关键词	RAINFALL-RUNOFF MODELS ; CLIMATE-CHANGE IMPACTS ; WATER-RESOURCES ; BIAS CORRECTION ; UNCERTAINTY ; PRECIPITATION ; VARIABILITY ; EVAPORATION ; INPUT
WOS类目	Environmental Sciences ; Environmental Studies
WOS研究方向	Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/315397
作者单位	1.Univ Tunis El Manar, LMHE, Ecole Natl Ingenieurs Tunis, BP 37 Le Belvedere, Tunis 1002, Tunisia; 2.Univ Carthage, Ecole Natl Architecture & Urbanisme, Sidi Bou Said, Tunisia; 3.Univ Zurich, Dept Geog, Zurich, Switzerland; 4.Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, Uppsala, Sweden; 5.Univ Melbourne, Dept Infrastruct Engn, Melbourne, Vic, Australia
推荐引用方式 GB/T 7714	Dakhlaoui, Hamouda,Seibert, Jan,Hakala, Kirsti. Sensitivity of discharge projections to potential evapotranspiration estimation in Northern Tunisia[J],2020,20(2).
APA	Dakhlaoui, Hamouda,Seibert, Jan,&Hakala, Kirsti.(2020).Sensitivity of discharge projections to potential evapotranspiration estimation in Northern Tunisia.REGIONAL ENVIRONMENTAL CHANGE,20(2).
MLA	Dakhlaoui, Hamouda,et al."Sensitivity of discharge projections to potential evapotranspiration estimation in Northern Tunisia".REGIONAL ENVIRONMENTAL CHANGE 20.2(2020).