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Originally Posted by ratbastid
Now, I've always understood that the water cycle is Earthbound--that no water ever LEAVES our planet.
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Technically, this isn't true. A tiny amount leaves when water vapor near the top of the atmosphere is exposed to UV radiation and dissociates. However, I think the rate at this is happening is dwarfed by the amount of water vapor that is put in to the atmosphere by volcanic eruptions.
Eventually, in billions of years, as the Sun gets brighter and heats up the Earth, more water vapor evaporates, which further heats up the Earth (water vapor is a greenhouse gas), and so on, and so on. This is a runaway greenhouse effect and would lead to the evaporation of the oceans.
For now, though, whereever you have severe droughts somewhere, that would be balanced by severe precipitation elsewhere. Keep in mind that 70% of the Earth is ocean, there could be record rains somewhere that we just can't directly measure/observe.