Stable sea surface temperatures in the western Pacific warm pool over the past 1.75?million years.
Saved in:
| Title: | Stable sea surface temperatures in the western Pacific warm pool over the past 1.75?million years. |
|---|---|
| Authors: | de Garidel-Thoron, Thibault, Rosenthal, Yair, Bassinot, Franck, Beaufort, Luc |
| Source: | Nature. 1/20/2005, Vol. 433 Issue 7023, p294-298. 5p. |
| Subjects: | Glacial climates, Climate change, Ocean temperature, Atmospheric carbon dioxide, Dynamic climatology, Upwelling (Oceanography) |
| Geographic Terms: | Pacific Ocean |
| Abstract: | About 850,000 years ago, the period of the glacial cycles changed from 41,000 to 100,000 years. This mid-Pleistocene climate transition has been attributed to global cooling, possibly caused by a decrease in atmospheric carbon dioxide concentrations. However, evidence for such cooling is currently restricted to the cool upwelling regions in the eastern equatorial oceans, although the tropical warm pools on the western side of the ocean basins are particularly sensitive to changes in radiative forcing. Here we present high-resolution records of sea surface temperatures spanning the past 1.75 million years, obtained from oxygen isotopes and Mg/Ca ratios in planktonic foraminifera from the western Pacific warm pool. In contrast with the eastern equatorial regions, sea surface temperatures in the western Pacific warm pool are relatively stable throughout the Pleistocene epoch, implying little long-term change in the tropical net radiation budget. Our results challenge the hypothesis of a gradual decrease in atmospheric carbon dioxide concentrations as a dominant trigger of the longer glacial cycles since 850,000 years ago. Instead, we infer that the temperature contrast across the equatorial Pacific Ocean increased, which might have had a significant influence on the mid-Pleistocene climate transition. [ABSTRACT FROM AUTHOR] |
| Copyright of Nature is the property of Springer Nature and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | Psychology and Behavioral Sciences Collection |
Be the first to leave a comment!
