Exploring downstream water availability of Yellow River based on historic and projected runoff change in the source region area

Summary

In recent years, the source region of Yellow River (SRYR, see Appendix A) has been subject to a changing climate which affects various water balance components as illustrated by the drawn-down of groundwater levels, decreased runoff, reduction of wetland and permafrost areas. The decreasing runoff from SRYR inevitably influences water availability downstream and creates an increasing vulnerability to water scarcity problems. A thorough understanding of the physical processes responsible for the runoff reduction can provide the insights needed for efficient present-day and future water management in Yellow River under water stress. In the proposed study, the following work will be carried out: (1) A land surface model Noah will be coupled with a hydrologic model WEP-L (see Appendix B) to provide a complete description of the water and energy land-atmosphere processes, (2) this modeling system will be validated against ground-based observations from Maqu soil moisture and temperature observe network (see Appendix C) and discharge data from Tangnaihai hydrological station, and (3) then used to identify the dominant process responsible for runoff change in SRYR, (4) the water allocation and regulation module (WARM) in WEP-L will be applied together with the developed modeling system to study the water demand and water availability in the downstream of Yellow River, (5) future water availability due to climate change and socio-economic driving forces derived from IPCC scenarios will be analyzed at last.