Northern Hemisphere Controls on Tropical Southeast African Climate During the Past 60,000 Years
Northern Hemisphere Controls on Tropical Southeast African Climate During the Past 60,000 Years
复制标题
DOI：
10.1126/science.1160485
复制
发表时间：
2008-10
期刊：
影响因子：
56.9
通讯作者：
J. Tierney;J. Russell;Y. Huang;J. Damsté;E. Hopmans;A. Cohen
中科院分区：
文献类型：
--
作者：
J. Tierney;J. Russell;Y. Huang;J. Damsté;E. Hopmans;A. Cohen
人们对控制热带气候的过程知之甚少。我们应用化合物特定的氢同位素（δD）和TEX 86（86个碳原子的四醚指数）温度代用品从坦噶尼喀湖沉积物岩心独立重建降水和温度变化在过去的60,000年。坦噶尼喀温度遵循北方半球的日照，表明在最后一次冰川终止期间，非洲东南部热带地区的变暖比大气中二氧化碳浓度早3000年开始增加。δD资料显示，该地区水文突变与北方半球季风气候记录中的轨道和千年尺度事件同期发生。这意味着，在热带东南非洲的降水更强烈地控制印度洋海面温度和冬季印度季风的变化，而不是热带辐合带的迁移。
The processes that control climate in the tropics are poorly understood. We applied compound-specific hydrogen isotopes (δD) and the TEX86 (tetraether index of 86 carbon atoms) temperature proxy to sediment cores from Lake Tanganyika to independently reconstruct precipitation and temperature variations during the past 60,000 years. Tanganyika temperatures follow Northern Hemisphere insolation and indicate that warming in tropical southeast Africa during the last glacial termination began to increase ∼3000 years before atmospheric carbon dioxide concentrations. δD data show that this region experienced abrupt changes in hydrology coeval with orbital and millennial-scale events recorded in Northern Hemisphere monsoonal climate records. This implies that precipitation in tropical southeast Africa is more strongly controlled by changes in Indian Ocean sea surface temperatures and the winter Indian monsoon than by migration of the Intertropical Convergence Zone.