Assessing Climate Change Impacts on Water Resources in the Songhua River Basin

Abstract

Abstract:The Songhua River Basin (SRB) in Northeast China is one of the areas most sensitive to global climate change because of its high-latitude location. In this study, we conducted a modeling assessment on the potential change of water resources in this region for the coming three decades using the Soil and Water Assessment Tool (SWAT). First, we calibrated and validated the model with historical streamflow records in this basin. Then, we applied the calibrated model for the period from 2020 to 2049 with the projected and downscaled climatic data under two emission scenarios (RCP 4.5 and RCP 8.5). The study results show: (1) The SWAT model performed very well for both the calibration and validation periods in the SRB; (2) The projected temperatures showed a steady, significant increase across the SRB under both scenarios, especially in two sub-basins, the Nenjiang River Basin (NRB) and the Lower SRB (LSRB). With regard to precipitation, both scenarios showed a decreasing trend in the NRB and LSRB but an increasing trend in the Upper Songhua River Basin (USRB); and (3), generally, the hydrologic modeling suggested a decreasing trend of streamflow for 2020-2049. Compared to baseline conditions , the streamflow in the NRB and LSRB would decrease by 20.3%-37.8%, while streamflow in the USRB would experience an increase of 9.68%-17.7%. These findings provide relevant insights into future surface water resources, and such information can be helpful for resource managers and policymakers to develop effective eco-environment management plans and strategies in the face of climate change.

Using SWAT and Fuzzy TOPSIS to Assess the Impact of Climate Change in the Headwaters of the Segura River Basin (SE Spain)

“…These results can also be compared to those obtained by Estrela et al [3], who also projected a reduction in mean annual runoff for the SRB between 21% and 33%. Overall, the increase in temperature and the projected decrease in precipitation will result in increased evapotranspiration, which will interact to reduce streamflow significantly [52]. Comparing precipitation and streamflow results, it can be seen that, due to higher actual evapotranspiration, the decreases obtained in streamflow exceed those in precipitation by 20%.…”

Quantification of Hydrological Responses Due to Climate Change and Human Activities over Various Time Scales in South Korea

“…The Budyko curve based on Budyko's assumption [36] is developed by two balance equations on water and energy. One is Equation (9), and the other is Equation (10), to represent the energy balance in a basin [52].…”

“…These studies dealt with gradual and abrupt trends in precipitation, temperature and runoff, and they found that climate change by global warming was likely to increase the incidence of extreme events, causing more severe floods and droughts [5][6][7][8][9]. Labat et al [10] found evidence for a 4% increase in global runoff with each 1 K increase in mean global temperature due to climate warming.…”

Nonlinear Response of Streamflow to Climate Change in High-Latitude Regions: A Case Study in Headwaters of Nenjiang River Basin in China’s Far Northeast

“…The warm-drying trend has contributed to considerable wetland degradation and agricultural hazards in Northeast China [37]. The continue decreasing in streamflow may possess a large pressure on surface and subsurface water resources [38][39][40]. This calls for more authority basin-wide regulations to manage water resources to meet the balance among agricultural sector, ecosystem and domestic water utility.…”