New Scientist: IT CONTAINS most of the world's land and 90 per cent of its people, but that is not why the northern hemisphere is consistently hotter than its southern counterpart. It turns out that ocean circulation is to blame.
The temperature disparity was first recorded by early 16th century explorers, who noticed icebergs floating in the southern hemisphere at latitudes where they wouldn't have been in the north. The northern hemisphere is currently 1.5 °C warmer on average than the southern hemisphere....