Why are annual temperature ranges in the Southern Hemisphere generally smaller than those in the Northern Hemisphere?
Climates in the southern hemisphere overall tend to be slightly milder than those in the northern hemisphere. This is because the southern hemisphere has significantly more ocean and less land. Water heats up and cools down more slowly than land. The southern hemisphere is also significantly less polluted than the northern hemisphere because of lower overall population densities (a total of 10 to 12% of the human population), lower levels of industrialisation, and smaller land masses (air currents run mostly west-east so pollution does not easily spread north or south).
