California Drought Linked to Human-Caused Warming: Study

In parched California, rainfall patterns are essentially the same as they were 120 years ago, but humans have made it warmer and that added heat is driving the state’s crippling drought, according to a new study. Warm temperatures dry out soils and cause precipitation to fall as rain rather than snow, thus reducing annual snowpack essential for irrigation, for example. What snow does fall then melts earlier in the spring.