A continuous record of surface temperature for the past 2650 years was obtained in an earlier study from a Beijing stalagmite based on sedimentary layer counting and thickness measurements.Singular spectrum analysis,m...A continuous record of surface temperature for the past 2650 years was obtained in an earlier study from a Beijing stalagmite based on sedimentary layer counting and thickness measurements.Singular spectrum analysis,multi-taper and wavelet spectral analyses are used in this study to identify decadal-scale signals and their origins in this record.Besides long-term cycles of solar origin identified in earlier studies,this record contains cycles that dominate temperature with periods of 102-70,66-50,31,25-22,19,15,12 and 9 years.The 102-70,25-22,12 and 9 year cycles are attributable to solar variation,while the others are likely to be related to low-latitude ocean forcing.These results suggest that century-scale changes in the Beijing summer temperature over the past 2650 years are primarily controlled by solar variation,while ocean-atmospheric interactions play a prominent role in modu-lating decadal-scale variability.展开更多
利用1980~2014年CRU TS3.24月平均气温数据和NCEP/NCAR再分析资料,分析了中国东北暖季(5~9月)气温的时空变化特征及其相应的大气环流状况。结果表明:中国东北暖季气温主要表现为全区一致型和南北反位相型两个模态,二者总解释方差高达86...利用1980~2014年CRU TS3.24月平均气温数据和NCEP/NCAR再分析资料,分析了中国东北暖季(5~9月)气温的时空变化特征及其相应的大气环流状况。结果表明:中国东北暖季气温主要表现为全区一致型和南北反位相型两个模态,二者总解释方差高达86%。全区一致型具有明显的年代际变化特征,并在1990年代中期发生了显著的年代际突变,而南北反位相型具有明显的年际和年代际变化特征。全区一致型增暖对应着中国东北地区上空500 h Pa位势高度的正异常和850 h Pa的反气旋环流异常。当500 h Pa位势高度南北反相时,对应于中国东北暖季气温的南北反位相型。进一步分析表明中国东北暖季气温的全区一致型及其1990年代中期的年代际突变与日本海及黑潮延伸区的海温异常及太平洋年代际振荡和大西洋多年代际振荡指数紧密相关。菲律宾以东的西太平洋、北太平洋中部、我国东南沿海、靠近北美东北部的北大西洋等海域的海温异常对中国东北暖季气温全区一致型的出现具有一定的预测作用。而南北反位相变化型与黑潮延伸区的海温异常关系显著,与大尺度指数的相关普遍不明显。在1990年代中期突变前,南北反位相型受到ENSO事件的影响,之后影响不显著。展开更多
基金supported by the National Basic Research Program of China(2010CB950200)
文摘A continuous record of surface temperature for the past 2650 years was obtained in an earlier study from a Beijing stalagmite based on sedimentary layer counting and thickness measurements.Singular spectrum analysis,multi-taper and wavelet spectral analyses are used in this study to identify decadal-scale signals and their origins in this record.Besides long-term cycles of solar origin identified in earlier studies,this record contains cycles that dominate temperature with periods of 102-70,66-50,31,25-22,19,15,12 and 9 years.The 102-70,25-22,12 and 9 year cycles are attributable to solar variation,while the others are likely to be related to low-latitude ocean forcing.These results suggest that century-scale changes in the Beijing summer temperature over the past 2650 years are primarily controlled by solar variation,while ocean-atmospheric interactions play a prominent role in modu-lating decadal-scale variability.
文摘利用1980~2014年CRU TS3.24月平均气温数据和NCEP/NCAR再分析资料,分析了中国东北暖季(5~9月)气温的时空变化特征及其相应的大气环流状况。结果表明:中国东北暖季气温主要表现为全区一致型和南北反位相型两个模态,二者总解释方差高达86%。全区一致型具有明显的年代际变化特征,并在1990年代中期发生了显著的年代际突变,而南北反位相型具有明显的年际和年代际变化特征。全区一致型增暖对应着中国东北地区上空500 h Pa位势高度的正异常和850 h Pa的反气旋环流异常。当500 h Pa位势高度南北反相时,对应于中国东北暖季气温的南北反位相型。进一步分析表明中国东北暖季气温的全区一致型及其1990年代中期的年代际突变与日本海及黑潮延伸区的海温异常及太平洋年代际振荡和大西洋多年代际振荡指数紧密相关。菲律宾以东的西太平洋、北太平洋中部、我国东南沿海、靠近北美东北部的北大西洋等海域的海温异常对中国东北暖季气温全区一致型的出现具有一定的预测作用。而南北反位相变化型与黑潮延伸区的海温异常关系显著,与大尺度指数的相关普遍不明显。在1990年代中期突变前,南北反位相型受到ENSO事件的影响,之后影响不显著。
