Which is, of course, all nonsense. It's the build up of year round ice and snow in the broad reaches of North America (mostly Canada) that really counts and which ultimately controls global climate.
In fact, it's the North American ice sheet that's always the big dog when it comes to a colder climate. Asia ends up with a smaller total glaciated area as well as a smaller total amount of ice as compared to North America.
South Asia (the Himalayas) become more glaciated but never become non-glaciated and may be considered a third permanent ice cap along with Greenland and Antarctica.
This last August an interesting South Pacific/South Atlantic, Mid-Pacific/Mid-Atlantic batch of winds blew toward South America, Middle America and North America and created a Northern Flow from literally Tierra Del Fuego to Baffin island. A tremendous amount of moisture was sucked into the flow ~ and fortunately was blown East across the North Atlantic before it could be turned into snow and ice in the Arctic.
That particular phenomenon doesn't usually happen but it was pretty obvious from satellite shots that if this continued for a month or two we could have a tremendous ice build up in North America ~ IN ONE SEASON. That's not like a thousand years, or a century, or a decade ~ that's like ONE SEASON.
It would change Earth's climate like flicking a switch.
Then again the state of North American ice sheets may depend on whether or not Firestone et al. are right or wrong about their NA boloid theory about 13,000 years ago.