Variable intensity of teleconnections during the late Holocene in subtropical North America from an isotopic study of speleothem from Florida



[1] The persistence and influence of both tropical and extra-tropical teleconnections on the hydrology of subtropical North America are little understood. Major atmospheric-oceanic controls on the isotopic composition of the precipitation reconstructed from a 1,000 year old stalagmite are the North Atlantic Oscillation (NAO) and the Pacific Decadal Oscillation (PDO). These teleconnections create decadal- to centennial-scale changes in the seasonal distribution of precipitation. An increase in the winter proportion of annual precipitation coincides with negative phase NAO conditions and a positive phase PDO. However, the PDO's influence appears to be weakened when it is out of phase with the El Niño Southern Oscillation (ENSO). The NAO exerts the greater decadal influence on this regions climate than the El Niño Southern Oscillation (ENSO), suggesting a greater significance of high latitude controls on subtropical North America.