Southern Hemisphere and Deep-Sea Warming Led Deglacial Atmospheric CO 2 Rise and Tropical Warming
Establishing what caused Earth's largest climatic changes in the past requires a precise knowledge of both the forcing and the regional responses. We determined the chronology of high- and low-latitude climate change at the last glacial termination by radiocarbon dating benthic and planktonic f...
| Published in: | Science |
|---|---|
| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
American Association for the Advancement of Science (AAAS)
2007
|
| Subjects: | |
| Online Access: | http://dx.doi.org/10.1126/science.1143791 https://www.science.org/doi/pdf/10.1126/science.1143791 |
| Summary: | Establishing what caused Earth's largest climatic changes in the past requires a precise knowledge of both the forcing and the regional responses. We determined the chronology of high- and low-latitude climate change at the last glacial termination by radiocarbon dating benthic and planktonic foraminiferal stable isotope and magnesium/calcium records from a marine core collected in the western tropical Pacific. Deep-sea temperatures warmed by ∼2°C between 19 and 17 thousand years before the present (ky B.P.), leading the rise in atmospheric CO 2 and tropical–surface-ocean warming by ∼1000 years. The cause of this deglacial deep-water warming does not lie within the tropics, nor can its early onset between 19 and 17 ky B.P. be attributed to CO 2 forcing. Increasing austral-spring insolation combined with sea-ice albedo feedbacks appear to be the key factors responsible for this warming. |
|---|