Abstract
The Medieval Climate Anomaly (MCA) was the most recent pre-industrial era warm interval of European climate, yet its driving mechanisms remain uncertain. We present here a 947-year-long multidecadal North Atlantic Oscillation (NAO) reconstruction and find a persistent positive NAO during the MCA. Supplementary reconstructions based on climate model results and proxy data indicate a clear shift to weaker NAO conditions into the Little Ice Age (LIA). Globally distributed proxy data suggest that this NAO shift is one aspect of a global MCA-LIA climate transition that probably was coupled to prevailing La Nina-like conditions amplified by an intensified Atlantic meridional overturning circulation during the MCA.
Original language | English |
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Pages (from-to) | 78-80 |
Number of pages | 3 |
Journal | Science |
Volume | 324 |
Issue number | 5923 |
DOIs | |
Publication status | Published - 1 Apr 2009 |