水力发电作为重要的可再生电源技术之一，在中国电力系统中占据着重要的位置。在气候变化的背景下，气候模式的变化不仅影响了降水量和降水模式，造成时空双重维度上的降水重新分配，更提高了极端降水事件发生的可能性。而降水因素的变化在综合温度等其他因素的变化后，会一定程度上改变径流规律，最终反映为径流量绝对值的变化和波动性的增加，从而对水电部门产生影响。因此，探究气候变化下中国水力发电的脆弱性对指导中国水电行业的建设和运营有现实意义；同时，也可对水电部门的满足减排贡献的能力做出预测。本文从水电发电量相对基年的偏离水平和预测期内发电量的波动程度两个角度出发，探究RCP 4.5和RCP 8.5两种排放情景下2020~2080年中国水电部门出力水平在时间和空间维度下的变化，分析其在气候变化下展现的脆弱性。研究结果表明：（1） RCP 4.5及RCP 8.5情景下全国年均水力发电量分别为8633.29亿千瓦时和8238.66亿千瓦时，较基年2015年分别增加2.50%和降低2.19%，呈现出较小的偏离水平，但不同时间段内不同区域的表现各有不同，体现出阶段性、区域性的风险。全国发电量在预测期内呈现先欠后丰、逐时间段提升的态势，以及向西南省份、长江流域和大型水电站集中的特点。（2） 从时间维度上看，大部分地区在2020~2040阶段面对发电量显著减少的风险；2040~2060阶段，大部分地区水电出力水平降低的风险有所缓解，但RCP 4.5情景下省份间发电水平偏离基准程度分化明显，可能产生较大的电力调配压力；而2060~2080阶段部分地区则可能有较大的弃水风险。（3） 从区域维度上看，预测期内云南省、新疆省等省份和海河、内陆河等流域的发电量一直较基年显著减少，表现出较大的区域脆弱性；另外，在高排放情景下，更多省份表现出了更大的波动性风险，或导致一定的区域电力调配压力。从电站装机维度上看，大型电站起到一定的锚定作用，可以有效支持水电部门的出力稳定性。
As an important renewable power source, the hydropower sector occupies an important position in China's energy mix. In the context of climate change, changes in climate patterns not only affect the precipitation and precipitation patterns, therefore causing redistribution of precipitation in the dimensions of time and space, but also increase the possibility of extreme precipitation events. The changes of precipitation and other relevant elements such as temperature end up in the changes of runoff rule in the perspectives of volume and volatility. Finally, these changes in runoff sector affects the production of hydropower. Therefore, exploring the impact of climate change on China's hydropower system is of great value in guiding the construction and operation of China's hydropower sector, and can also predict the contribution of hydropower sector to the goal of emission reduction.From the perspective of the deviation of power generation from the base year and the fluctuation of power generation during the forecast period, this paper explores the changes of China's hydropower production from 2020 to 2080 under RCP 4.5 scenario and RCP 8.5 scenario from both time and space dimensions, analysis the vulnerability of this sector caused by climate change. Research shows that:(1) The average annual power generation during forecasting period of the RCP 4.5 scenario and RCP 8.5 scenario are 863.33 billion kWh and 823.87 billion kWh, which means respectively an increase of 2.50% and a decrease of 2.19% from the base year level of 2015. Although the national average production shows a small deviation level, the deviations in different regions during different period are quite different. Therefore, phased and regional risks appear. During the forecast period, the national power generation shows a first decrease and then increase pattern, and concentrates to the southwestern provinces, the Yangtze River basin and the giant hydropower stations. (2) From the perspective of time dimension, most regions face the vulnerability of significantly reduced power generation in the 2020~2040 phase. In the 2040~2060 phase, the vulnerability caused by power generation reduction in most regions is released by some extent, but the regional power generation variation is larger than last period under the RCP 4.5 scenario, which causes regional power distribution pressure. In the 2060~2080 phase, some areas may face the risk of water abandonment. (3) From a regional perspective, during the forecast period, the power generation in provinces such as Yunnan Province, Xinjiang Province, and river basins like Haihe River Basin and Inland Rivers have been significantly reduced comparing with the base year, showing a large regional vulnerability. In addition, under the high emission scenario (RCP 8.5), more provinces have shown greater volatility risk, which may lead to regional electricity transmission pressure. From the perspective of the installed capacity of the power station, the giant power stations have an obvious anchoring effect on hydropower generation sector. Huge stations effectively stabilize the output level of hydropower sector within the forecast period.
