基于Anusplin插值的广东省近50年日照时数时空特征

Spatiotemporal Characteristics of 50-year Sunshine Duration for the Province of Guangdong Based on the Anusplin Interpolation

基于1971—2020年广东省国家气象站点数据,采用Anusplin插值以及Morlet小波来分析广东省日照时数空间栅格数据以及时间序列周期变化规律。结果表明:(1)广东省年均日照时数的变化范围为1052.3~2185.9 h,平均日照时数为1713.8 h,呈现南多北少、东西多中间少的分布规律。四季平均日照时数多寡依次为:夏(564.45 h)>秋(536.12 h)>冬(357.61 h)>春(300.13 h)。(2)Anusplin插值法验证结果在Anusplin、Kriging和IDW 3种插值方法中精度最优,更能准确体现实际日照时数空间分布。(3)在时间变化趋势上全省大都呈现减少趋势,其中中部减少显著,高海拔地区最为明显。变化周期主要有5~15、18~24、28~34、38~44、52~58年,未来几年在20年及以下的中小尺度上年日照时数开始转为偏少时期,而在30年及以上的大尺度上则处于偏多时期。

Based on the data from the national meteorological observation stations in Guangdong from 1971 to 2020 and with the methods of Anusplin interpolation and Morlet wavelet analysis,this work studies the spatial lattices of the provincial sunshine duration and the periodical variation patterns of its temporal series.The result is shown as follows.(1)The annual mean sunshine duration of Guangdong varies within the range from 1052.3 to 2185.9 h with an average of 1713.8 h,distributing more in the southern,eastern and western parts than in the northern and central parts of the province.Seasonal average sunshine duration tops in summer(564.45 h),followed in turn by autumn(536.12 h),winter(357.61 h)and spring(300.13 h).(2)Reflecting actual spatial distribution of the sunshine duration more accurately,the Anusplin interpolation is the method that has better verification result as compared to either the Kriging or the IDW method.(3)With regard to temporal variation,the sunshine duration shows a general decreasing trend across the province,significantly in the central part and most significantly in high-altitude localities.The variation of sunshine duration is periodical mainly at 5 to 15,18 to 24,28 to 34,38 to 44,and 52 to 58 years,with periods on the medium-to-small scales(20 years or less)decreasing,and those on the large scale(30 years or more)increasing,in the few years to come.