基于SPI指数的当前及未来中国东北地区干旱时空演变特征分析

基于降水量历史观测数据和气候模式预估数据,采用标准化降水量指数(Standandized Precipitation Index, SPI)识别干旱事件,从干旱发生的频率和强度特征分析其危险性,研究东北地区当前及未来不同气候变化情景下干旱时空变化特征。结果显示:(1)bcc-csm1-1对东北地区降水的模拟效果较好;(2)东北地区年降水量东南多西部少,未来远期较近期降水增幅更为明显,中、西部地区降水增幅略高于其他地区;(3)仅在RCP8.5情景下未来近期研究区中部地区干旱有加重的趋势,主要源于该时段夏季降水的变化,其余时段皆呈干旱危险性减弱。

Spatial and temporal characteristics of drought in Northeast China at present and future climate change based on SPI

Most of the past related researchers were focus on drought characteristics during the past few decades. While it is also important to study the drought at future for the purpose of adapting climate change and reducing disaster risk. In this research, precipitation by observation and model simulation were used to calculate Standardized Precipitation Index (SPI), which could be used to identify drought events. By combining drought frequency and intensity to assess drought hazard in a region, then to study the spatial and temporal characteristics of drought hazard at present and future climate change. The results show that: (1) bcc-csm1-1 has better simulation effect on monthly precipitation in Northeast China among the Global Climate Model (GCMs). (2) Precipitation had a decreasing trend from southeast to western area in Northeast China. Precipitation increments were larger during 2070-2099 than 2020-2049 and they were larger in the middle than surrounding area. (3) Drought hazard decreased in Northeast China in the future, except for the middle of the study area under RCP8.5 during 2020-2049.