There is no observational evidence of changes during the past two decades in the flow across the Greenland–Scotland Ridge, which connects the North Atlantic with the Norwegian and Greenland Seas. Direct current measurements since the mid-1990s have not shown any significant trends in volume transport for any of the three inflow branches (Østerhus et al., 2005; Hansen et al., 2010; Mauritzen et al., 2011; Jónsson and Valdimarsson, 2012).
The two primary pathways for the deep southward overflows across the Greenland–Scotland Ridge are the Denmark Strait and Faroe Bank Channel. Moored measurements of the Denmark Strait overflow demonstrate significant interannual transport variations (Macrander et al., 2005; Jochumsen et al., 2012), but the time series is not long enough to detect a multi-decadal trend. Similarly, a 10-year time series of moored measurements in the Faroe Bank channel (Olsen et al., 2008) does not show a trend in transport.