Now desert, then lakes. The climate has been changing ever since there was an Earth.
Bush’s fault...
It would also would be interesting as compared and contrasted to modern theories of global warming (which I think are nonsense). For example what would happen if the desolation of the Gobi could be linked to a decrease in atmospheric CO2? We might discover that a CO2 concentration of 1,000 ppb is much more conducive to life on Earth and in that case, burn away!