1960-2022年洞庭湖流域气温和降水时空演变特征OA

[Objective]The study aims to reveal the trends,periodicity,and spatiotemporal evolution characteristics of tem-perature and precipitation in the Dongting Lake Basin over the past 63 years,providing a scientific basis for the prevention of flood and drought disasters in the region.[Methods]The Mann-Kendall method and wavelet analysis were used to analyze the trends,periodicity,and spatial characteristics of temperature and precipitation in the Dongting Lake Basin and its four main river sub-basins,Lishui River,Yuanjiang River,Zijiang River,and Xiangjiang River.[Results](1)From 1960 to 2022,the annual average temperature in the four sub-basins showed an extremely significant increasing trend,while the annual average precipitation showed a non-significant variation trend.Both temperature and precipitation were unevenly distributed within the year.(2)The main cycle of temperature in the four sub-basins was about 20 years.The precipitation periodicity in the Lishui sub-basin was significantly different from the other three sub-basins.Its main cycle of precipitation was 3 years,while the other three sub-basins had a main cycle of about 24 years.(3)The spatial distribution and evolution trends of tem-perature and precipitation across the Dongting Lake Basin were distinctly different.Both temperature and precipitation showed a decreasing trend from southeast to northwest.The overall temperature trend showed an increase of 0.07-0.48℃/(10 years).The spatial distribution of precipitation trends in the Dongting Lake Basin featured a greater difference with a range of-24.34-48.54 mm/(10 years).The precipitation in most areas showed an increasing trend,while decreases occurred in the northwestern and central-southern parts.[Conclusion]The climate of the Dongting Lake Basin over the past 63 years has in-dicated a warming trend,but the trend toward increased precipitation is not obvious.