Historical and future climates over the upper and middle reaches of the Yellow River Basin simulated by a regional climate model in CORDEX

Abstract

Despite the importance of the Yellow River to China, climate change for the middle reaches of the Yellow River Basin (YRB) has been investigated far less than for other regions. This work focuses on future changes in mean and extreme climate of the YRB for the near-term (2021–2040), mid-term (2041–2060), and far-term (2081–2100) future, and assesses these with respect to the reference period (1986–2005) using the latest REgional MOdel (REMO) simulations, driven by three global climate models (GCMs) and assuming historical and future [Representative Concentration Pathway (RCP) 2.6 and 8.5] forcing scenarios, over the CORDEX East Asia domain at 0.22° horizontal resolution. The results show that REMO reproduces the historical mean climate state and selected extreme climate indices reasonably well, although some cold and wet biases exist. Increases in mean temperature are strongest for the far-term in winter, with an average increase of 5.6 °C under RCP 8.5. As expected, the future temperatures of the warmest day (TXx) and coldest night (TNn) increase and the number of frost days (FD) declines considerably. Changes to mean temperature and FD depend on elevation, which could be explained by the snow-albedo feedback. A substantial increase in precipitation (34%) occurs in winter under RCP 8.5 for the far-term. Interannual variability in precipitation is projected to increase, indicating a future climate with more extreme events compared to that of today. Future daily precipitation intensity and maximum 5-day precipitation would increase and the number of consecutive dry days would decline under RCP 8.5. The results highlight that pronounced warming at high altitudes and more intense rainfall could cause increased future flood risk in the YRB, if a high GHG emission pathway is realized.

The Runoff in the Upper Taohe River Basin and Its Responses to Climate Change

“…The precipitation results of other models have some common results and some noncommon ones, but the precipitation results of the RCMs are quite heterogeneous. Different simulation ranges, physical parameterization schemes, dynamic frameworks, and atmospheric boundary condition data will have a greater impact on precipitation [19]. Conditional data will have a greater impact on precipitation.…”

“…Compared to global models, regional climate models (RCMs) with higher resolutions can not only describe the characteristics of large-scale circulation, but also accurately capture the characteristics of climate change at the regional scale [17][18][19]. Different scenarios generate different prediction trends for future climate change and have been widely used in global and regional climate change predictions.…”

Bias correction, historical evaluations, and future projections of climate simulations in the Wei River Basin using CORDEX-EA

“…Both are the hydrostatic regional climate model. The dynamic model of the former is the same as that of the hydrostatic version of the fifth generation Penn State/NCAR Mesoscale Model , the latter uses physical parameterizations from European Centre Hamburg Version 4 (Roeckner et al 1996) and a dynamical framework from the weather forecast model of the German Weather Service Europa-Modell (Wang et al 2021). The RegCM4-4 and REMO2015 have successfully applied to multiple domains (i.e.…”

“…For the cold biases in the WRB, they may be caused by the cold biases of simulations or the warm biases of observations. The former may be inherited from the GCMs (Wang et al 2021), and be attributed to inadequate representation of physical processes, such as overestimated topographic forcing and snow cover (Tapiador et al 2020;Pang et al 2021). The latter may be connected with the fact that most meteorological stations are located in valleys, making the observations include warm biases for high altitude areas (Wang et al 2016).…”

Impacts of Permafrost Degradation on Hydrology and Vegetation in the Source Area of the Yellow River on Northeastern Qinghai-Tibet Plateau, Southwest China

“…Since the 1950s, the SAYR has undergone significant warming and this warming will continue in coupling with more and frequent extreme weather events (Wang et al, 2021). Permafrost in the SAYR is warm (≥−1 °C) and discontinuous (<90% in areal extent of permafrost), and occupies an areal extent of 25,000 km 2 , or 85%, of the areal extent of the SAYR above the Tanag hydrological station, Qinghai Province, China (Li J. et al, 2016;Sheng et al, 2020;Cao H. et al, 2021).…”