Time-slice reconstructions of ocean circulation changes on the continental shelf in the Nordic and Barents Seas during the last 16,000 cal yr B.P.

Abstract

Ocean circulation changes along the continental shelf of the Nordic and Barents Seas have been investigated in order to reconstruct regional changes in the inflow of Atlantic Water (AW) through the last 16,000 calibrated (cal) years (yr) B.P. We have selected five time-slices representing the late glacial (16,000–15,000 cal yr B.P.), the Bølling-Allerød warm interstadials (14,500–13,500 cal yr B.P.), the Younger Dryas cold stadial (12,500–11,500 cal yr B.P.), the early Holocene (9500–7500 cal yr B.P.) and the late Holocene (4000–2000 cal yr B.P.). Twelve previously published records of the distribution of benthic foraminifera faunas and ice-rafted debris have been compiled. The earliest sign of Atlantic Water inflow was recorded at the northern Iceland shelf at 16,000–15,000 cal yr B.P. The inflow of warm AW to the Nordic Seas shelf has been persistent since, but with variable strength and geographic pattern. An apparent zonal seesaw pattern in the strength of the Norwegian Atlantic Current (NwAC) and the Irminger Current (IC) during the late glacial, Bølling-Allerød and Younger Dryas periods was found. During the Holocene, no zonal differences in the inflows of NwAC and IC were found. A strong meridional gradient with warmer conditions at lower latitudes and relatively cold conditions at high northern latitudes existed.