Rapid 20th-century increase in coastal upwelling off northwest Africa.
نویسندگان
چکیده
Near-shore waters along the northwest African margin are characterized by coastal upwelling and represent one of the world's major upwelling regions. Sea surface temperature (SST) records from Moroccan sediment cores, extending back 2500 years, reveal anomalous and unprecedented cooling during the 20th century, which is consistent with increased upwelling. Upwelling-driven SSTs also vary out of phase with millennial-scale changes in Northern Hemisphere temperature anomalies (NHTAs) and show relatively warm conditions during the Little Ice Age and relatively cool conditions during the Medieval Warm Period. Together, these results suggest that coastal upwelling varies with NHTAs and that upwelling off northwest Africa may continue to intensify as global warming and atmospheric CO2 levels increase.
منابع مشابه
Rapid 20th-century increase in coastal upwelling off northwest Africa revealed by high-resolution marine sediment cores
PAGES News, Vol.15 • No 2 • September 2007 Rapid 20th-century increase in coastal upwelling off northwest Africa revealed by high-resolution marine sediment cores helen v. mCGreGor1,2 and stefan mulitza3,4 Institute for Environmental Research, ANSTO, Lucas Heights, Australia; [email protected]; School of Earth and Environmental Sciences, University of Wollongong, Australia; DFG Research Ce...
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ورودعنوان ژورنال:
- Science
دوره 315 5812 شماره
صفحات -
تاریخ انتشار 2007