You can't make it up LI - sometimes climate change is good, and sometimes it isn't (11 mar 14)
According to the authoritative New Zealand website, "horsetalk.co.nz", 800 years ago, a warming climate helped Mongolia. Fortunately (for the Mongols), it was accompanied by increased rainfall. Today, however, it is accompanied by drought. No danger of Mongol invasions now. http://horsetalk.co.nz/2014/03/11/climate-fueled-rise-horse-numbers-crucial-great-empire-study
Talking of Mongolia, one thing has always puzzled me. When a Mongolian baby is born with Down's syndrome, how can they tell?