El Niño/La Niña and Sahel Precipitation During the Middle Holocene
نویسنده
چکیده
Simulations with a synchronously coupled atmosphere-land-ocean-sea ice model indicate El Niño/La Niña-like events in the eastern tropical Pacific Ocean during the middle Holocene (6 ka) with similar intensities and frequencies as at present (0 ka). July-August-September Sahel precipitation shifts northward as expected from proxy data. For presentday, interannual-decadal variability of western Sahel precipitation is correlated with both Pacific El Niño/La Niña sea surface temperature (SST) anomalies and the Atlantic dipole. Teleconnections at 6 ka between Sahel precipitation and El Niño/La Niña SST anomalies are absent with tropical Atlantic SSTs asserting a dominant influence. These results illustrate potential problems with using present-day teleconnection patterns in interpreting past climate variability from proxy data.
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