7 The question of why, in the annual-mean, the Northern Hemisphere (NH) is warmer than 8 the Southern Hemisphere (SH) is addressed, revisiting an 1870 paper by James Croll. We 9 first show that ocean is warmer than land in general which, acting alone, would make the 10 SH, with greater ocean fraction, warmer. Croll was aware of this and thought it was caused 11 by greater specific humidity and ...
