Something I can’t get my head around is why they think the climate on the edge of the ice sheet - - especially when they talk about Eurasia - - was so dry. What the heck happened in the summer? The ice sheet would have melted some at the edges and refroze in the winter. And to get a layer of ice two miles thick, it would have had to snow....
A LOT.
The are lots of cold climates in the world today that are very dry.
Rain comes from clouds. Clouds form over bodies of water and swamp land. When there is no water (only snow and ice)upwind from you, there are no clouds.
In the case of deserts moist air rising over mountain ranges cools causing rain and snow to fall and dries the air. There is no moisture left to fall on the downwind side.