Drier, warmer springs in US Southwest stem from human-caused changes in winds

The late-winter/early-spring storm activity in the western US has shifted north since the late 1970s. This graphic shows how the peak winter storm tracks have shifted poleward since 1978. The blue line shows the storm track for February, March and April of 1978. The red line shows the track for the same months during the year 1997. Credit: Stephanie McAfee, the University of Arizona, 2008.