气候变化领域集成服务门户(CCPortal): Analyzing the future climate change of Upper Blue Nile River basin using statistical downscaling techniques

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DOI	10.5194/hess-22-2391-2018
	Analyzing the future climate change of Upper Blue Nile River basin using statistical downscaling techniques
	Fenta Mekonnen D.; Disse M.
发表日期	2018
ISSN	1027-5606
起始页码	2391
结束页码	2408
卷号	22 期号:4
英文摘要	Climate change is becoming one of the most threatening issues for the world today in terms of its global context and its response to environmental and socioeconomic drivers. However, large uncertainties between different general circulation models (GCMs) and coarse spatial resolutions make it difficult to use the outputs of GCMs directly, especially for sustainable water management at regional scale, which introduces the need for downscaling techniques using a multimodel approach. This study aims (i) to evaluate the comparative performance of two widely used statistical downscaling techniques, namely the Long Ashton Research Station Weather Generator (LARS-WG) and the Statistical Downscaling Model (SDSM), and (ii) to downscale future climate scenarios of precipitation, maximum temperature (Tmax) and minimum temperature (Tmin) of the Upper Blue Nile River basin at finer spatial and temporal scales to suit further hydrological impact studies. The calibration and validation result illustrates that both downscaling techniques (LARS-WG and SDSM) have shown comparable and good ability to simulate the current local climate variables. Further quantitative and qualitative comparative performance evaluation was done by equally weighted and varying weights of statistical indexes for precipitation only. The evaluation result showed that SDSM using the canESM2 CMIP5 GCM was able to reproduce more accurate long-term mean monthly precipitation but LARS-WG performed best in capturing the extreme events and distribution of daily precipitation in the whole data range. Six selected multimodel CMIP3 GCMs, namely HadCM3, GFDL-CM2.1, ECHAM5-OM, CCSM3, MRI-CGCM2.3.2 and CSIRO-MK3 GCMs, were used for downscaling climate scenarios by the LARS-WG model. The result from the ensemble mean of the six GCM showed an increasing trend for precipitation, Tmax and Tmin. The relative change in precipitation ranged from 1.0 to 14.4ĝ€% while the change for mean annual Tmax may increase from 0.4 to 4.3ĝ€°C and the change for mean annual Tmin may increase from 0.3 to 4.1ĝ€°C. The individual result of the HadCM3 GCM has a good agreement with the ensemble mean result. HadCM3 from CMIP3 using A2a and B2a scenarios and canESM2 from CMIP5 GCMs under RCP2.6, RCP4.5 and RCP8.5 scenarios were downscaled by SDSM. The result from the two GCMs under five different scenarios agrees with the increasing direction of three climate variables (precipitation, Tmax and Tmin). The relative change of the downscaled mean annual precipitation ranges from 2.1 to 43.8ĝ€% while the change for mean annual Tmax and Tmin may increase in the range from 0.4 to 2.9ĝ€°C and from 0.3 to 1.6ĝ€°C respectively. © Author(s) 2018.
语种	英语
scopus关键词	Climate models; Water conservation; Water management; Watersheds; Calibration and validations; Future climate scenarios; General circulation model; Mean annual precipitation; Spatial and temporal scale; Statistical downscaling; Statistical downscaling model (SDSM); Sustainable water management; Climate change; climate change; CMIP; comparative study; downscaling; future prospect; general circulation model; model; performance assessment; precipitation (climatology); scenario analysis; spatial resolution; temperature; water management; Blue Nile Basin; Nile Basin
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/160050
作者单位	Fenta Mekonnen, D., Department of Hydrology and River Basin Management, Faculty of Civil, Geo and Environmental Engineering, Technische Universität München, Arcisstrasse 21, Munich, 80333, Germany, Amhara National Regional State Water, Irrigation and Energy Development Bureau, Bahirdar, Ethiopia; Disse, M., Department of Hydrology and River Basin Management, Faculty of Civil, Geo and Environmental Engineering, Technische Universität München, Arcisstrasse 21, Munich, 80333, Germany
推荐引用方式 GB/T 7714	Fenta Mekonnen D.,Disse M.. Analyzing the future climate change of Upper Blue Nile River basin using statistical downscaling techniques[J],2018,22(4).
APA	Fenta Mekonnen D.,&Disse M..(2018).Analyzing the future climate change of Upper Blue Nile River basin using statistical downscaling techniques.Hydrology and Earth System Sciences,22(4).
MLA	Fenta Mekonnen D.,et al."Analyzing the future climate change of Upper Blue Nile River basin using statistical downscaling techniques".Hydrology and Earth System Sciences 22.4(2018).