How a map at +4 or +6 degrees may or may not look is pretty far from "grade school", and definitely requires sources. I agree that the map in the parent comment doesn't meet my standards for scientific accuracy, due to lack of sources, but that doesn't mean I'd discount it. It's not exactly implausible, extrapolating from current desertification. Seems like the map is from a book (https://www.paragkhanna.com/home/2016/3/9/the-world-4-degree...), so presumably that book would contain explanations. Your Smithsonian map is quite bad, too: It contains no legend, an no explanations at all, although based on the coloring it would seem that there's less desertification than in the parent comment map. But then, it also looks like due to continental drift, the majority of landmass was on the Southern hemisphere. I think it's pretty silly to draw too many conclusions about desertification in the next century from a picture of the earth 170 million years ago, with a completely different distribution of land mass and weather patterns.