1961-2021年贵州省日平均气温<10℃气候特征分析

Climate Characteristics of Daily Mean Temperature Below 10℃in Guizhou Province from 1961 to 2021

贵州省冬季供暖需求呈上升趋势,而气温<10℃成为冬季能源保供气象服务中的重要指标。利用1961-2021年贵州省82个国家级地面气象观测站逐日平均气温资料,对日平均气温<10℃日数时空分布特征进行分析。结果表明:贵州省日平均气温<10℃日期主要集中在11月下旬—次年3月上旬,呈西北多、南部少的空间分布特征;秋、冬、春季日平均气温<10℃日数呈减少趋势,其中春季减少最快;日平均气温<10℃平均开始(结束)日期由西北向南逐渐推迟(提前),20世纪90年代末以来开始/结束时间呈现明显偏晚/偏早特征;各地年日平均气温<10℃日数突变时间集中在20世纪90年代至21世纪初,南部早于北部,突变后年日平均气温<10℃日数减少特征明显,其中自东向西中部一线减少显著;年日平均气温<10℃日数存在10~12 a、4~6 a和3 a左右的显著振荡周期,其中3 a左右的振荡周期最为显著;日平均气温<10℃日数多少除了受海拔影响外,还受地理位置和天气系统等因素的影响。

Using daily mean temperature data from 82 national meteorological observation stations in Guizhou Province from 1961 to 2021,the spatiotemporal distribution characteristics of days with daily mean temperature below 10℃are analyzed.The results show that the time period with daily mean temperature below 10℃in Guizhou Province ranges mainly from late November to early March,showing a spatial distribution feature of more in the northwest and less in the south.The number of days with daily mean temperature below 10℃in autumn,winter,and spring tends to decrease,with the fastest decrease occurring in spring.The average start(end)date with daily mean temperature below 10℃is gradually delayed(advanced)from northwest to south.Since the late 1990s,the start(end)date have shown a significant tendency to be later(earlier).The mutation of annual days with daily mean temperature below 10℃concentrated in the 1990s–2000s,showing a distribution pattern where the southern regions experienced mutations earlier than the northern regions.After the mutation,the number of days with daily mean temperature below 10℃decreased significantly,with a significant decrease in the central region from east to west.There are significant oscillation periods of 10-12 years,4-6 years,and 3 years for annual days with daily mean temperature below 10℃in Guizhou Province,with the oscillation period of 3 years being the most significant.The distribution of the number of days with daily mean temperature below 10℃is not only influenced by altitude,but also by factors such as geographical location and weather system.