排序方式: 共有3条查询结果,搜索用时 0 毫秒
1
1.
2.
High-resolution record of Northern Hemisphere climate extending into the last interglacial period 总被引:4,自引:0,他引:4
Andersen KK Azuma N Barnola JM Bigler M Biscaye P Caillon N Chappellaz J Clausen HB Dahl-Jensen D Fischer H Flückiger J Fritzsche D Fujii Y Goto-Azuma K Grønvold K Gundestrup NS Hansson M Huber C Hvidberg CS Johnsen SJ Jonsell U Jouzel J Kipfstuhl S Landais A Leuenberger M Lorrain R Masson-Delmotte V Miller H Motoyama H Narita H Popp T Rasmussen SO Raynaud D Rothlisberger R Ruth U Samyn D Schwander J Shoji H Siggard-Andersen ML Steffensen JP Stocker T Sveinbjörnsdóttir AE Svensson A Takata M 《Nature》2004,431(7005):147-151
Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time. 相似文献
3.
1