Spatial and Temporal Analysis of Extreme Climate Events over Northeast China

In recent years, the frequent occurrence of extreme climate disasters has seriously affected agriculture in Northeast China. Based on precipitation data derived from 83 geographical stations in the study area for 60 years (1960-2019), we chose the reliable statistical methods of the Mann-Kendall test, Sen's slope, and the Standardized Precipitation Index, and regarded drought and flood as a whole in this paper, to identify the temporal and spatial variation characteristics of precipitation and extreme climate events in Northeast China. The results show that an increasing trend of disasters was detected at the 95% confidence level (Z = 2.3). According to the timescale analysis, abrupt climate changes started in 2006. Temporal and spatial distribution of extreme climate disasters, mainly drought and flood disasters, showed a significant upward trend from 2006 to 2019. According to the spatial analysis, the precipitation in Northeast China decreased from south to north and fluctuated less from east to west. Moreover, stations with extreme climate trends (trend of climatic anomaly with confidence level > 90%) followed the same spatial pattern as those with a high frequency of extreme climate disasters (more than 17.87 times/decade). The severity and frequency of extreme climate have increasingly threatened Northeast China in the past decade. In particular, the Northeast Plain experienced the most severe and extreme climate events that seriously threatened the study area in 2007, 2009, 2010, and 2019. Our results highlight the urgent need for the development of monitoring and early warning of droughts and flood disasters to reduce economic losses.

Automated summary

In recent years, frequent extreme climate disasters in Northeast China have seriously impacted agriculture. Based on precipitation data from 83 geographical stations over a 60-year period, this study identified the temporal and spatial variation characteristics of precipitation and extreme climate events. The results showed an increasing trend of disasters, with abrupt climate changes starting in 2006. The severity and frequency of extreme climate have posed a growing threat to Northeast China, particularly in the past decade.