Abstract
Recurrent phases of increased pine at Lake
Tulane, Florida have previously been related to strong
stadials terminated by so-called Heinrich events. The climatic
significance of these pine phases has been interpreted
in different ways. Using a pollen–climate inference model,
we quantified the climate changes and consistently
found that mean summer precipitation (PJJA) increased
(0.5–0.9 mm/day) and mean November temperature
increased (2.0–3.0 C) during pine phases coeval with
Heinrich events and the Younger Dryas. Marine sea surface
temperature records indicate that potential sources for these
moisture and heat anomalies are in the Gulf of Mexico and
the western tropical Atlantic. We explain this low latitude
warming by an increased Loop Current facilitated by persistence
of the Atlantic Warm Pool during summer. This
hypothesis is supported by a climate model sensitivity
analysis. A positive heat anomaly in the Gulf of Mexico
and equatorial Atlantic best approximates the polleninferred
climate reconstructions from Lake Tulane during
the (stadials around) Heinrich events and the Younger
Dryas.Recurrent phases of increased pine at Lake
Tulane, Florida have previously been related to strong
stadials terminated by so-called Heinrich events. The climatic
significance of these pine phases has been interpreted
in different ways. Using a pollen–climate inference model,
we quantified the climate changes and consistently
found that mean summer precipitation (PJJA) increased
(0.5–0.9 mm/day) and mean November temperature
increased (2.0–3.0 C) during pine phases coeval with
Heinrich events and the Younger Dryas. Marine sea surface
temperature records indicate that potential sources for these
moisture and heat anomalies are in the Gulf of Mexico and
the western tropical Atlantic. We explain this low latitude
warming by an increased Loop Current facilitated by persistence
of the Atlantic Warm Pool during summer. This
hypothesis is supported by a climate model sensitivity
analysis. A positive heat anomaly in the Gulf of Mexico
and equatorial Atlantic best approximates the polleninferred
climate reconstructions from Lake Tulane during
the (stadials around) Heinrich events and the Younger
Dryas.
Original language | English |
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Pages (from-to) | 109-118 |
Number of pages | 10 |
Journal | Climate Dynamics |
Volume | 36 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - Jan 2011 |
Keywords
- Heinrich events
- Abrupt climate change
- Atlantic Warm Pool
- Loop Current
- Low latitudes
- Florida