Impact of Climate Change on Reservoir Operation during the Dry Season in the Pearl River Basin

Abstract

Climate change has far-reaching impacts that have created new challenges for water resource management. As an important measure to coordinate the relationship between society, economy, and environment, reservoir scheduling can reduce the future impact of climate change. It is, therefore, important to investigate the impacts of scheduling on reservoir operation. In this study, a reservoir system in the Pearl River Basin was selected to explore these impacts. Results show that the basin temperature significantly and abruptly increased in 2000, and precipitation and streamflow changed abruptly in 1983 and 1992. Historically, climate change has increased power generation, increased the risks to water supply security and ecological protection, and altered the relationship between power generation and ecological protection objectives. Based on 28 global climate models, the rank scoring method, Delta statistical downscaling, and the SWAT model, three emission scenarios (RCP2.6, RCP4.5, and RCP8.5) in CMCC-CM were evaluated to assess the climate change impact. In the future, the temperature will continue to exhibit an increasing trend, and the amount and distribution of streamflow will be altered. Although climate change will increase power generation in the dry season, it will also bring about new challenges for ecological protection and water supply security. Accordingly, the Datengxia Reservoir operating rules may require significant amendments.