News release: “The weather patterns that typically bring moisture to the southwestern United States are becoming more rare, an indication that the region is sliding into the drier climate state predicted by global models, according to a new study. “A normal year in the Southwest is now drier than it once was,” said Andreas Prein, a postdoctoral researcher at the National Center for Atmospheric Research (NCAR) who led the study. “If you have a drought nowadays, it will be more severe because our base state is drier. Climate models generally agree that human-caused climate change will push the southwestern United States to become drier. And in recent years, the region has been stricken by drought. But linking model predictions to changes on the ground is challenging. In the new study–published online today in the journal Geophysical Research Letters, a publication of the American Geophysical Union–NCAR researchers grapple with the root cause of current drying in the Southwest to better understand how it might be connected to a warming climate.”