Jianyu Liu, Qiang Zhang^*, Yongqiang Zhang, Xi Chen, Jianfeng Li, Santosh K Aryal

[Jianyu Liu]. Department of Water Resources and Environment, Sun Yat-sen University, Guangzhou 510275, China.

[Qiang Zhang]. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China.

[Qiang Zhang]. State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China.

[Qiang Zhang]. Faculty of Geographical Science, Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China.

[Yongqiang Zhang, Santosh K Aryal]. CSIRO Land and Water, GPO Box 1700, Canberra ACT 2601, Australia.

[Xi Chen]. School of Hydrology and Water Resources, Hohai University, Nanjing 210098, China.

[Jianfeng Li]. Department of Geography, Hong Kong Baptist University, Hong Kong, China.

ABSTRACT: Climatic elasticity has been widely applied to assess streamflow responses to climate changes. To fully assess impacts of climate under global warming on streamflow and reduce the error and uncertainty from various control variables, we develop a four-parameter (precipitation, catchment characteristics n, maximum and minimum temperature) climatic elasticity method named PnT, based on the widely used Budyko framework and simplified Makkink equation. We use this method to carry out the first comprehensive evaluation of the streamflow response to potential climate change for 372 widely spread catchments in China. The PnT climatic elasticity was firstly evaluated for a period 1980-2000, and then used to evaluate streamflow change response to climate change based on 12 global climate models (GCMs) under Representative Concentration Pathway 2.6 (RCP2.6) and RCP 8.5 emission scenarios. The results show that: (1) the PnT climatic elasticity method is reliable; (2) projected increasing streamflow takes place in more than 60% of the selected catchments, with mean increments of 9% and 15.4% under RCP2.6 and RCP8.5 respectively; (3) uncertainties in the projected streamflow are considerable in several regions, such as the Pearl River and Yellow River, with more than 40% of the selected catchments showing inconsistent change directions. Our results can help Chinese policy makers to manage and plan water resources more effectively, and the PnT climatic elasticity should be applied to other parts of the world.

Published in Journal of Geophysical Research, 2017, DOI: 10.1002/2017JD026701.