California Getting Wetter to the North, Drier to the South: Natural Variability or Climate Change?

States that current climate change projections anticipate that global warming trends will lead to changes in the distribution and intensity of precipitation at a global level
States that few studies have corroborated these model-based results using historical precipitation records at a regional level, especially in California
Analyzes 14 long-term precipitation records representing multiple climates throughout the state
Finds northern and central regions increasing in precipitation while southern regions are drying
Finds that winter precipitation is increasing in all regions, while other seasons show mixed results
Finds that rain intensity has not changed since the 1920s
Finds that while Sacramento shows over 3 more days of rain per year, Los Angeles has almost 4 less days per year in the last century
Finds that both the El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) greatly influence the California precipitation record
Concludes that the climate change signal in the precipitation records remains unclear as annual variability overwhelms the precipitation trends