Abstract
The abrupt Northern Hemispheric warming at the end of the twentieth century has been attributed to an enhanced greenhouse effect. Yet Greenland and surrounding subpolar North Atlantic remained anomalously cold in 1970s to early 1990s. Here we reconstructed robust Greenland temperature records (North Greenland Ice Core Project and Greenland Ice Sheet Project 2) over the past 2100years using argon and nitrogen isotopes in air trapped within ice cores and show that this cold anomaly was part of a recursive pattern of antiphase Greenland temperature responses to solar variability with a possible multidecadal lag. We hypothesize that high solar activity during the modern solar maximum (approximately 1950s-1980s) resulted in a cooling over Greenland and surrounding subpolar North Atlantic through the slowdown of Atlantic Meridional Overturning Circulation with atmospheric feedback processes.
Original language | English |
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Pages (from-to) | 5992-5999 |
Number of pages | 8 |
Journal | Geophysical Research Letters |
Volume | 42 |
Issue number | 14 |
DOIs | |
Publication status | Published - 28 Jul 2015 |
Keywords
- Atlantic meridional overturning circulation
- Greenland
- ice core
- paleoclimate
- subpolar North Atlantic
- temperature
Programme Area
- Programme Area 5: Nature and Climate