Has this person ever been to Texas? Texas is not a monoclimate, but if he's proposing that all the land is parched then he's thinking west Texas. Where is all his fireplace wood coming from - there are very few trees there. How does he expect people to live there without A/C? How will these rooftop gardens survive the near constant and drying winds? As someone who has been to Amarillo more times than I wanted to, I don't think this is in any way realistic. If instead we assume this town is say within an hour of Houston - there are different concerns, but being perpetually parched is not on of them.