Future climate projection under IPCC A1B scenario in the source region of Yellow River with complex topography using RegCM3

Abstract

Located on the Tibetan Plateau, the source region of Yellow River has experienced remarkable climate change over past a few decades, which affects the regional ecosystem, agricultural development, and water availability. In this paper, high-resolution RegCM3 driven by ECHAM5 is applied to generate both control climate for 1980-2000 and regional climate projections for the 21 st century under the Intergovernmental Panel on Climate Change (IPCC) A1B emission scenario. For control climate, RegCM3 can well reproduce the spatial patterns of precipitation and surface air temperature with more detailed representation of fine scale topography. Wet and cold biases are produced in the simulation, but overall improvement by RegCM3 is evident compared to the driving global climate model (GCM) of ECHAM5. In the future projection, the model demonstrates significant warming over the whole analysis domain. Precipitation on the other hand shows mixed signals of reduction and increase over simulation domain, while the areas of precipitation reduction extend with increasing integration time and finally cover most parts of the domain at the end of 21 st century. As projection time increases, high altitude region will experience more precipitation reduction in summer and less reduction or even increase in winter. The winter warming at the high elevation area gets more evident than that at the low elevation area, which may be due to the snow feedback. Analyzing the change of probability distributions of surface climate, it can be concluded that the frequency of heavy precipitation in winter tends to increase with time indicating more extreme precipitation events in the future. The spectrum of temperature probability density functions (PDFs) moves toward higher end.

Climate change projections over China using regional climate models forced by two CMIP5 global models. Part II: projections of future climate

“…The severe warming in the regions with high altitude like the Tibetan Plateau has been attributed to the snow albedo feedback by Hui et al . ().…”

Hydrological projections of future climate change over the source region of Yellow River and Yangtze River in the Tibetan Plateau: A comprehensive assessment by coupling RegCM4 and VIC model

“…Thus, in the future, some improvements can be made to better develop the skill of the VIC model in simulating glacier melt run‐off, which would be significant for hydrologic prediction in alpine regions. Moreover, an offline modelling approach, assuming that hydrological simulations are conducted as an independent process to climate models, was widely used to assess climate change effects in the present researches (Hui et al, ; Su et al, ; Z. X. Xu et al, ), whereas feedback effects between two models are also of great importance for investigating the responses of hydrological regimes to climate impacts (Y. Q. Wang et al, ). Therefore, further efforts are needed in exploring the coupled regional modelling systems, which consider the feedback effects at proper spatial and temporal scales.…”

“…In this context, RCMs offer another necessary alternative based on clear physical principles, through which the finer scale can be constructed and climatic time series can be simulated at scales much closer to the requirement by hydrological models with credible estimation of change in inter‐annual variability (Arnell et al, ). In RCMs, reliable simulation and prediction of the atmospheric features on local scale can be explicitly provided by using detailed local features and the coarse‐scale GCM outputs (Hong & Kanamitsu, ; Hui, Tang, Wang, Wu, & Kang, ). Different with the statistical downscaling methods that depend on the actual meteorological stations to downscale the projections from the original CMIP5 models, improved resolution in RCMs leads to a better representation of finer scale physical process, as well as effects of details in topography, land–sea distribution, and land surface processes even in the ungauged regions (J. H. Christensen et al, ; Hewitson et al, ).…”

“…As the first and second longest rivers in China, respectively, both Yellow River and Yangtze River originate from the TP, providing precious water resource for vast basin areas and supporting the livelihood of millions of people (Huang et al, ; Hui et al, ). The source region of Yellow River covers only 16.2% of the whole Yellow River basin area but contributes more than 40% to the total run‐off (L. Li, Shen, Dai, Xiao, & Shi, ).…”

“…As the first and second longest rivers in China, respectively, both Yellow River and Yangtze River originate from the TP, providing precious water resource for vast basin areas and supporting the livelihood of millions of people (Huang et al, 2016;Hui et al, 2015).…”