以中国北方215块表土孢粉样品分析结果中的13种花粉类型与4种气候参数为基础资料建立花粉-气候因子转换函数。同时选取内蒙中部调角海子DJ钻孔岩芯高分辨率孢粉分析结果为材料,定量重建该地区10000～2100 a BP古气候因子数值特征。研究...以中国北方215块表土孢粉样品分析结果中的13种花粉类型与4种气候参数为基础资料建立花粉-气候因子转换函数。同时选取内蒙中部调角海子DJ钻孔岩芯高分辨率孢粉分析结果为材料,定量重建该地区10000～2100 a BP古气候因子数值特征。研究结果表明:内蒙古调角海子地区进入全新世后温湿状况较前全新世有了明显好转,在中全新世形成最为良好的气候要素组合。最高年平均温度比现在高4℃左右,最低年平均温度比现在低2℃左右。7月份和1月份平均温度的分析结果表明,1月份平均温度变化趋势较7月份的更接近年平均温度的变化趋势,说明该地区冬季温度占主导地位。在气候转折时期,气温和降水随时间的变化梯度明显加强,波动幅度为4～5℃。展开更多
The annually cross-dated stable carbon isotope of tree-ring a-cellulose of Abies spectabibis collected from the southeastern Tibetan Plateau is used to examine its rela-tionship with climatic parameters. The residual ...The annually cross-dated stable carbon isotope of tree-ring a-cellulose of Abies spectabibis collected from the southeastern Tibetan Plateau is used to examine its rela-tionship with climatic parameters. The residual D13C series in treerings is constructed after removing the effects of age trend and rising CO2. We found a close relationship between D13C in tree rings and the relative humidity of September—November of the previous year measured at the nearby Ny-ingchi Meteorological Station, albeit a strong 搇agged effect? Thus we developed a transfer function to reconstruct the autumn relative humidity for the Nyingchi region, which explained 37.9% of the total variance (p < 0.001). Our results suggest a high frequency and moderate amplitude variance of the relative humidity before 1800, and the variance re-versed afterwards.展开更多
The El Nino events for 1870—1989 were identified according to the sea surface temperature(SST)over the eastern equatorial Pacific(0—10°S,90—180°W)and Southern Oscillation Index.The chronicle of the El Nin...The El Nino events for 1870—1989 were identified according to the sea surface temperature(SST)over the eastern equatorial Pacific(0—10°S,90—180°W)and Southern Oscillation Index.The chronicle of the El Nino events in histori- cal time(14708—1879)was reconstructed by using of a series of proxy data such as Australian droughts,Nile floods, Peruvian floods,numbers of landing typhoon in China,cool summers in East Asia,SOI calculated from tree ring data, and El Nino events identified mainly from meteorological and oceanographical conditions along the Ecuador and Peru coast. Finally,114 El Nino events were found for the period 1470—1989.The mean return interval was 4.5 years.The fre- quency of the events seems to have a cyclical variation of 70 years.No close relationship was found between the global warming and the frequency of El Nino events.展开更多
文摘以中国北方215块表土孢粉样品分析结果中的13种花粉类型与4种气候参数为基础资料建立花粉-气候因子转换函数。同时选取内蒙中部调角海子DJ钻孔岩芯高分辨率孢粉分析结果为材料,定量重建该地区10000～2100 a BP古气候因子数值特征。研究结果表明:内蒙古调角海子地区进入全新世后温湿状况较前全新世有了明显好转,在中全新世形成最为良好的气候要素组合。最高年平均温度比现在高4℃左右,最低年平均温度比现在低2℃左右。7月份和1月份平均温度的分析结果表明,1月份平均温度变化趋势较7月份的更接近年平均温度的变化趋势,说明该地区冬季温度占主导地位。在气候转折时期,气温和降水随时间的变化梯度明显加强,波动幅度为4～5℃。
文摘The annually cross-dated stable carbon isotope of tree-ring a-cellulose of Abies spectabibis collected from the southeastern Tibetan Plateau is used to examine its rela-tionship with climatic parameters. The residual D13C series in treerings is constructed after removing the effects of age trend and rising CO2. We found a close relationship between D13C in tree rings and the relative humidity of September—November of the previous year measured at the nearby Ny-ingchi Meteorological Station, albeit a strong 搇agged effect? Thus we developed a transfer function to reconstruct the autumn relative humidity for the Nyingchi region, which explained 37.9% of the total variance (p < 0.001). Our results suggest a high frequency and moderate amplitude variance of the relative humidity before 1800, and the variance re-versed afterwards.
文摘The El Nino events for 1870—1989 were identified according to the sea surface temperature(SST)over the eastern equatorial Pacific(0—10°S,90—180°W)and Southern Oscillation Index.The chronicle of the El Nino events in histori- cal time(14708—1879)was reconstructed by using of a series of proxy data such as Australian droughts,Nile floods, Peruvian floods,numbers of landing typhoon in China,cool summers in East Asia,SOI calculated from tree ring data, and El Nino events identified mainly from meteorological and oceanographical conditions along the Ecuador and Peru coast. Finally,114 El Nino events were found for the period 1470—1989.The mean return interval was 4.5 years.The fre- quency of the events seems to have a cyclical variation of 70 years.No close relationship was found between the global warming and the frequency of El Nino events.
