1961—2014年中原核心区干旱事件时空变化特征

TEMPORAL AND SPATIAL CHARACTERISTICS OF DROUGHT EVENTS IN THE CENTRAL PLAINS DURING 1961—2014

关键词:  干旱  频率  中原核心区  气候变化  时空特征

Key words:  drought  frequency  Central Plains core area  climate change  temporal and spatial characteristics

摘要:

目的 通过对中原核心区降水指标分析，揭示该区域54年干旱事件的时空变化特征。方法 文章基于1961—2014年中原核心区23个国家级气象站点的逐日降水资料，采用降水量距平百分率、线性回归等方法，对年均降水量、干旱频率、干旱等级等年尺度和季节尺度的干旱事件的时空变化特征进行了分析。结果 （1）中原核心区降水波动性大，多年平均降水量总体呈减少趋势，干旱事件多发的态势，各干旱等级发生频次的排序为轻旱＞中旱＞特旱＞重旱；冬季是干旱的高发季节且呈现出重发的态势。（2）中原核心区多年平均降水量呈现出自东南向西北递减的带状分布特征。就区域而言，郑州干旱的发生频率最高且旱情较重。中原核心区发生高频次干旱的范围随年代际逐渐缩小。就季节而言，郑州为春季和冬季干旱的高发地，开封和洛阳西部是夏季干旱的高发地，洛阳北部和开封东部为秋季干旱的高发地。结论 中原核心区干旱事件呈增加趋势。研究结果可为该区域有针对性地抗旱减灾提供科学支撑。

Abstract:

Through the analysis of precipitation index in the Central Plains, the temporal and spatial variation characteristics of drought events in the past 54 years are revealed. Based on the daily precipitation data of 23 meteorological stations in the Central Plains core area from 1961 to 2014, the variation characteristics (i.e. annual and seasonal precipitation, drought frequency, anomaly value and drought grade) of drought events were studied by means of precipitation anomaly percentage and linear regression. The results showed that: (1) The precipitation in the core area of the Central Plains fluctuated greatly, and the average precipitation over the years showed a decreasing trend. Drought events occurred frequently. The order of the frequency of each drought level was light drought > medium drought > special drought > heavy drought; winter was the high season of drought and presented a heavy situation. (2) The annual average precipitation in the core area of the Central Plains showed a zonal distribution from southeast to northwest. As far as the region was concerned, the frequency of drought was the highest and the drought was more serious in Zhengzhou. The range of high frequency droughts in the core area of the Central Plains had gradually narrowed down with the age. In terms of seasons, Zhengzhou was the high incidence of spring and winter drought, Kaifeng and Western Luoyang were the high incidence of summer drought, and Northern Luoyang and Eastern Kaifeng were the high incidence of autumn drought. The analysis results in the past 54 years showed that the drought events in the central plains are increasing. This study is of great significance to the rational agricultural production, food security, economic development and ecological environment protection, and it also can provide favorable information support for drought resistance and disaster reduction in this area.