There are no two ways about it: Humankind is, for the first time in our recorded history, living through a massive global climate shift of our own making. Science paints today's crisis as unprecedented in scope and consequence. But that doesn't mean there aren't historical cases of societies that have enjoyed the highs and endured the lows of natural climatic changes -- from civilization-busting droughts to empire-building stretches of gorgeous sunshine.
Whether they're commanding marauding armies or struggling with dramatic temperature shifts, today's leaders have a variety of historical role models they can learn from:
Should Gov. Jerry Brown -- confronted by California's 500-year drought -- be mindful of the policy mistakes made by the last Ming emperor?
Will President Obama learn lessons from Ponhea Yat, the last king of the sacred city of Angkor Wat, when planning how to safeguard America's critical infrastructure against extreme weather?
Here are four historical figures whose triumphs and defeats were related, at least in part, to major changes in their climates.