The annual temperature range at most latitudes in the Southern Hemisphere is much smaller than that in the Northern Hemisphere. The reason for this is that .

Water must gain or lose large amounts of energy when its temperature changes.

Explanation:

Due to the presence of the more water bodies in the southern hemisphere and less of them in the northern hemisphere the annual range of the temperatures in the southern ocean is much smaller.  As compared to that of the north and water needs more energy to lose temperature hence the northern hemisphere has more of the landmass thus more temperature.

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