I grew up in Houston. This would require a technology for air conditioning the parks.
To your point though, the big desert cities (whether in Texas or Arizona or elsewhere) would not exist without AC.
I lived in both Arizona and Texas, and the issue is only supersonically the same. But even given that, I must agree with the spirit of the parent comment remark. Though, having spent some time in both Tucson and Phoenix, I'd strongly argue that the heat island affect just makes a bad situation worse. Replacing concrete with parks is a win virtually 100% of the time in that regard. Not to mention quality of life. The out door shopping in AZ and CA is much more pleasant than that of the strip mall experience.