基于标准化降水蒸散指数的中国东部季风区干旱特征分析

研究基于标准化降水蒸散指数,采用0.5°×0.5°中国地面气温和降水数据集,通过分析东部季风区季节和年尺度干旱覆盖率、频率以及单位面积干旱强度,揭示了中国东部季风区1961—2013年干旱特征时空分布变化。研究结果表明：近20 a东部季风区干旱特征变化明显,特别是1997年之后东部季风区干旱覆盖率和单位面积干旱强度显著增加;东北地区、华北平原、黄土高原和西南地区干旱频率增加,高频率覆盖范围扩大明显;气象干旱极端危险区扩大。全球变暖背景下东部季风区干旱呈现出极端化趋势。

Analysis of Drought Characteristics of the East China Monsoon Area Based on Standardized Precipitation Evapotranspiration Index

In this paper, the gridded Chinese ground precipitation and temperature dataset with spatial resolution of 0.5°× 0.5° released by National Meteorological Information Center and the standardized precipitation evapotranspiration index (SPEI) were used to analyze the drought coverage rate, the occurrence frequency of drought, and the intensity of drought in unit area. It reveals the temporal and spatial variations of drought characteristics in East China monsoon region from 1961 to 2013. The results showed that there were obvious changes of drought characteristics in the East China monsoon area in recent 20 years; the drought coverage rate and the intensity of drought per unit area had significant growing trend; the occurrence frequency of droughts had grown in Northeast China, North China, Loess Plateau and Southwest China; the areas with high frequencies of droughts and the extremely danger areas had obviously expanded. There was an externalized trend of drought in East China monsoon area under the background of global warming.