气候变化领域集成服务门户(CCPortal): Diagnosis of future changes in hydrology for a Canadian Rockies headwater basin

CCPortal

DOI	10.5194/hess-24-2731-2020
	Diagnosis of future changes in hydrology for a Canadian Rockies headwater basin
	Fang X.; W. Pomeroy J.
发表日期	2020
ISSN	1027-5606
起始页码	2731
结束页码	2754
卷号	24 期号:5
英文摘要	Climate change is anticipated to impact the hydrology of the Saskatchewan River, which originates in the Canadian Rockies mountain range. To better understand the climate change impacts in the mountain headwaters of this basin, a physically based hydrological model was developed for this basin using the Cold Regions Hydrological Modelling platform (CRHM) for Marmot Creek Research Basin ( 9:4 km2), located in the Front Ranges of the Canadian Rockies. Marmot Creek is composed of ecozones ranging from montane forests to alpine tundra and alpine exposed rock and includes both large and small clearcuts. The model included blowing and intercepted snow redistribution, sublimation, energy-balance snowmelt, slope and canopy effects on melt, Penman-Monteith evapotranspiration, infiltration to frozen and unfrozen soils, hillslope hydrology, streamflow routing, and groundwater components and was parameterised without calibration from streamflow. Nearsurface outputs from the 4 km Weather Research and Forecasting (WRF) model were bias-corrected using the quantile delta mapping method with respect to meteorological data from five stations located from low-elevation montane forests to alpine ridgetops and running over October 2005- September 2013. The bias-corrected WRF outputs during a current period (2005-2013) and a future pseudo global warming period (PGW, 2091-2099) were used to drive model simulations to assess changes in Marmot Creek's hydrology. Under a business-as-usual forcing scenario, Representative Concentration Pathway 8.5 (RCP8.5) in PGW, the basin will warm up by 4.7 C and receive 16% more precipitation, which will lead to a 40mm decline in seasonal peak snowpack, 84mm decrease in snowmelt volume, 0.2mmd1 slower melt rate, and 49 d shorter snow-cover duration. The alpine snow season will be shortened by almost 1.5 months, but at some lower elevations there will be large decreases in peak snowpack ( 45 %) in addition to a shorter snow season. Declines in the peak snowpack will be much greater in learcuts than under mature forest canopies. In alpine and treeline ecozones, blowing snow transport and sublimation will be suppressed by higher-threshold wind speeds for transport, in forest ecozones, sublimation losses from intercepted snow will decrease due to faster unloading and drip, and throughout the basin, evapotranspiration will increase due to a longer snow-free season and more rainfall. Runoff will begin earlier in all ecozones, but, as a result of variability in surface and subsurface hydrology, forested and alpine ecozones will generate the greatest runoff volumetric increases, ranging from 12% to 25 %, whereas the treeline ecozone will have a small (2 %) decrease in runoff volume due to decreased melt volumes from smaller snowdrifts. The shift in timing in streamflow will be notable, with 236% higher flows in spring months and 12% lower flows in summer and 13% higher flows in early fall. Overall, Marmot Creek's annual streamflow discharge will increase by 18% with PGW, without a change in its streamflow generation efficiency, despite its basin shifting from primarily snowmelt runoff towards rainfall-dominated runoff generation. © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License.
语种	英语
scopus关键词	Climate models; Digital storage; Evapotranspiration; Frozen soils; Global warming; Groundwater; Hydrology; Landforms; Mapping; Rain; Runoff; Snow; Snow melting systems; Stream flow; Sublimation; Unloading; Weather forecasting; Climate change impact; Hydrological modeling; Hydrological modelling; Snow cover durations; Snow redistributions; Streamflow generations; Subsurface hydrology; Weather research and forecasting models; Forestry; blowing snow; climate change; climate effect; detection method; future prospect; headwater; hydrological modeling; hydrological response; montane forest; rainfall-runoff modeling; streamflow; tundra; Alberta; Canada; Colorado; Front Range; Marmot Creek; Rocky Mountains; Saskatchewan River; Marmota
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/159393
作者单位	Fang, X., Centre for Hydrology, University of Saskatchewan, Saskatoon, S7N1K2, Canada; W. Pomeroy, J., Centre for Hydrology, University of Saskatchewan, Saskatoon, S7N1K2, Canada
推荐引用方式 GB/T 7714	Fang X.,W. Pomeroy J.. Diagnosis of future changes in hydrology for a Canadian Rockies headwater basin[J],2020,24(5).
APA	Fang X.,&W. Pomeroy J..(2020).Diagnosis of future changes in hydrology for a Canadian Rockies headwater basin.Hydrology and Earth System Sciences,24(5).
MLA	Fang X.,et al."Diagnosis of future changes in hydrology for a Canadian Rockies headwater basin".Hydrology and Earth System Sciences 24.5(2020).