Abstract
Noble gases in ice cores enable reconstructions of past mean ocean temperature. A recent result from the clathrate‐containing WAIS Divide Ice Core showed tight covariation between ocean and Antarctic temperatures throughout the last deglaciation, except for the Younger Dryas interval. In the beginning of this interval oceans warmed at 2.5°C/kyr ‐ three times greater than estimates of modern warming. If valid, this challenges our understanding of the mechanisms controlling ocean heat uptake. Here we reconstruct mean ocean temperature with clathrate‐free ice samples from Taylor Glacier to test these findings. The two records agree in net temperature change over the Younger Dryas, but the Taylor Glacier record suggests sustained warming at the more modest rate of 1.1±0.2°C/kyr. We explore mechanisms to explain differences between records and suggest that the noble gas content for the Younger Dryas interval of WAIS Divide may have been altered by a decimeter‐scale fractionation during bubble‐clathrate transformation.
Original language | English |
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Pages (from-to) | 5928-5936 |
Journal | Geophysical Research Letters |
Volume | 46 |
Issue number | 11 |
Early online date | 7 Jun 2019 |
DOIs | |
Publication status | Published - 16 Jun 2019 |
Keywords
- ice cores
- ocean heat uptake
- Younger Dryas
- bubble-to-clathrate formation
- paleoclimate