there is nothing mentioning polar shifts? We had glaciers here in the US until not too many hundreds years ago...
Our magnetic poles have constantly moved throughout history and at times even reversed. This could cause massive climate changes. unaccounted for in this article.
What about the phenomena that we are currently experiencing that will cool us down rapidly? The planet earth is in the midst of a 'celestial dust storm' our solar system is currently passing through a dense (in space terms) cloud of dust that is filtering a portion of our sun's heat and light. We can only hope for our internal "global warming CO-2" to help us maintain temperatures.
food for thought///
Any idea what a mechanism linking earth's magnetism and climate might be?