a positive trendP < 0.01
In the subpolar North Atlantic, the averaged OHU increases rapidly before 2050 (0.139 W m −2 year −1 , P < 0.01) and levels off or declines slightly after that, which corresponds to a positive trend of 0.045 W m −2 year −1 ( P < 0.01) during 2006–2100.