Global Climate
What's the climate like now in the world?

It's probably easy to assume that everything is pretty much warmer, with places being sunk by global warming, yadda yadda. Do you think that anywhere still has regular snow? Like places that'd normally be cold. Greenland, Russia, Sweden, etc. Antarctica probably gets that too regardless, right?

And would already hot places even be livable without bio-domes or whatever anymore? The American Southwest, Africa, so on? Or would they just be heated up to the point of being sun cracked wastelands with zero life.

Yes it still snows in some places. Climate change is not a unilateral shift toward a hotter and dryer world. In some places it gets colder and wetter. The general idea is that it's enormously disruptive to civilization (see: Southeast Asia, The East Coast of the US) and makes farming incredibly difficult, necessitating a shift to vat food and weather-controlled agri-domes.

Sindome's world is bad and all fucked up, but it is not a giant desert.