Yale Environment 360: Over the past three years of severe drought, California has accumulated a rain "debt" equal to a year's worth of precipitation, NASA researchers report in the Journal of Geophysical Research Atmospheres. The state is roughly 20 inches behind in total precipitation, the scientists calculate, which is the average amount expected to fall in the state in a single year. The deficit has been driven primarily by a lack of extreme precipitation events known as atmospheric rivers water vapor-rich air...