Houses in a small beach resort in southeast St. Johns County, Florida.Aerial_Views/ Getty ImagesThe climate crisis is an often-hidden financial risk when buying a house.A few online tools can help you assess that risk and possible costs by address.Here's how to check extreme-weather threats to a house and identify upgrades that can help.If you're shopping for a house, you're probably thinking ahead and planning for your future.Here's the thing, though: By the end of a 30-year mortgage, you'll be living on a pretty different planet.Even if companies and governments across the world make some drastic changes — and that's a big "if" — humanity's carbon emissions have already locked in some additional warming for decades to come.