"We have estimated an increase of 24 x 1022 J representing a volume mean warming of 0.09°C of the 0-2000 m layer of the World Ocean. If this heat were instantly transferred to the lower 10 km of the global atmosphere it would result in a volume mean warming of this atmospheric layer by approximately 36°C (65°F)."(This is because the heat capacity [= mass x specific heat][= dQ/dT, where Q is heat and T is temperature] of the ocean is about 1,000 times that of the atmosphere.) Lest you worry, they add:
"This transfer of course will not happen; earth’s climate system simply does not work like this. But this computation does provide a perspective on the amount of heating that the earth system has undergone since 1955."