From 2008 to 2011, Cal Water, a 3-year program, mostly land-based but using Dewey G1 aircraft for one winter, was instigated by the Californian Energy Commission, and supported by NOAA and Scripps in response to the decreasing precipitation and snow pack. It looked at the role of atmospheric rivers penetrating inland and the role of aerosols in modulating clouds and precipitation over the Sierra.
Climate scientists claim that global warming amplifies the risk factors for extreme weather events such as floods and droughts. Rising temperatures increase evaporation and evapotranspiration which adds moisture to the atmosphere whilst taking it from soil, plants and water bodies, increasing the frequency and intensity of droughts. As the atmosphere holds more water, the risk of extreme rainfall events increases. Under our hypothesis positing the introduction of an over-seeding regime of aerosols into the upper atmosphere, this retention of water followed by eventual deluges would be greatly exacerbated.