摘要
利用黔东南地区16个地面气象观测站1961-2010年逐月地面0-20cm浅层地温和气温实测资料,分别统计四季浅层地气温差的时间序列,采用正交函数分解(EOF)、经验模态分解(EMD)、Mann-Kendall突变检验等方法,分析各季浅层地气温差的空间分布结构和时间演变特征。结果表明,黔东南各季浅层地气温差均为正值,说明浅层地温高于气温,但各季节的时空分布存在较大差异,其中秋季最大,春季最小;受大尺度气候异常影响,各季变化大值中心分布不同,在一定程度上地形和海拔对浅层地气温差有较大影响,次区域特征存在明显差异;各季浅层地气温差的振荡模态中,重要分量均是第一分量(IMF1),即55%由2～4a的年际变化造成,IMF1和IMF2决定着浅层地气温差的变化,IMF4以后的分量表征浅层地气温差的年代际变化。在全球气候变暖的背景下,黔东南地区春、秋季的地气温差表现为显著的增加趋势(P<0.05),夏、冬季总体变化趋势不明显,90年代以后夏季为增加趋势(P<0.05)。近50a黔东南各季浅层地气温差的突变点不一致,春季和秋季在20世纪70年代发生了突变(P<0.05),夏季和冬季的突变出现在90年代,说明各季浅层地气温差的变化存在明显的阶段性和地域性差异。
Based on the monthly temperature of 0 -20cm soil and air temperature of 16 stations in southeast Guizhou province from 1961 to 2010, the series of temperature difference from soil to air （ referred to as Ts-Ta） in four seasons were calculated respectively. The spatial distribution and changing tendency was analyzed by using of orthogonal func- tion decomposition （EOF） , empirical mode decomposition （EMD） and Mann- Kendall methods. The results showed that the value of Ts-Ta was positive in every season, but there was big difference in spatial and temporal distributions among seasons, in which highest value occurred in winter and lowest value in spring. The distribution of the highest value center was different each quarter as affected by large-scale climate anomalies. The first component （IMF1） was important component in oscillation mode of Ts-Ta in each season. Ts-Ta in spring and autumn showed obvious increase （ P 〈 0. 05 ） in last 50 years in southeast Guizhou, but not obviously in winter and summer. The mutation point of Ts- Ta in spring and autumn occurred in 1970s, and that in winter and summer occurred in 1990s, which indicated that the change of Ts-Ta had obvious stage and regional differences in every season.
出处
《中国农业气象》
CSCD
北大核心
2012年第1期71-77,85,共8页
Chinese Journal of Agrometeorology
基金
贵州省科学技术基金项目[2009]2043
关键词
黔东南地区
浅层地气温差
EOF分析
EMD分析
Southeast Guizhou
Soil-air temperature difference （Ts-Ta）
EOF analysis
EMD analysis
