why would it cause drought?....I mean global warming caused drought, right?
Ice ages caused drought in equatorial regions because so much water was frozen in glaciers.
Locks up a lot of water in the ice caps. That water can't fall as rain.
Warming OTOH, frees up water, and increases evaporation from the oceans. It's got rain out somewhere. But changed circulation patterns could mean that it gets drier some places, and a lot wetter in others, but overall it should be wetter, like the old 30s and 40s Science Fiction versions of the Venusian swamps.