Rainstorms continue to pummel the Pacific Northwest in the U.S. and British Columbia in Canada this fall, causing extensive flooding and damage. A weather pattern known as an atmospheric river carries moisture from the ocean onto land. Studies indicate climate change is making the region's atmospheric rivers warmer, more frequent and more intense. The region is known for rain, but not of such sustained intensity and warmth, says National Center for Atmospheric Research climate scientist Daniel Swain. He said that is why there's been extreme flooding.