Circulation and overturning in the eastern North Atlantic subpolar gyre

This study describes new transport estimates of the North Atlantic Current in Iceland Basin, and uses these results along with other contemporaneous measurements to determine mass overturning budgets for eastern subpolar gyre. As part Overturning Subpolar Program (OSNAP), are determined using three full-depth dynamic height moorings spanning Basin supplemented by Argo satellite altimetry data. Along historical exchanges over Iceland-Scotland Ridge, additional OSNAP from Rockall Trough Rockall-Hatton Bank regions used calculate different density layers a broad portion Results show that 13–14 Sv (σθ < 27.8 kg m−3) flow northward into middle through primary baroclinic near 23.5°W secondary quasi-barotropic 26°W. Together observed area, we conclude 19–20 upper limb Meridional Circulation 27.56 flows region where nearly 40 % it (7.3 Sv) is converted lower primarily progressive water modification atmospheric cooling. accounts half strength defined full array extending across basin Greenland Scotland.