No, we can’t say exactly how much responsibility man-made global warming bears for the massive storm that slammed into the Northeast at the end of the October, killing over 100, flooding chunks of New York City and leaving more than 8 million people without power. But we do know that climate change—especially because of rising sea levels—is likely to make the Sandys of the future that much more dangerous. One thing should be clear: with nearly 4 million Americans living within a few feet of high tide, we need to better prepare our coastal cities for the storms to come.