Authors: Erica Bigio*, University of Arizona, Connie Woodhouse, University of Arizona, Dave Meko, University of Arizona, Dan Griffin, University of Minnesota
Topics: Climatology and Meteorology, Environmental Science, Global Change
Keywords: drought, California, dendrochronology, paleoclimate
Session Type: Paper
Start / End Time: 3:20 PM / 5:00 PM
Room: Grand Ballroom C, Astor, 2nd Floor
Presentation File: No File Uploaded
The recent drought in California (2012 – 2016) caused severe water shortages in both rural and urban communities, and drought impacts included crop loss, extensive wildfires, and economic losses. Drought over the years 2012-2015 was record-breaking statewide, and drought impacts were intensified by warming temperatures in the recent decades. To provide a long-term context for this extreme drought, we developed seven streamflow or precipitation reconstructions for southern California, including the Kern River in the southern Sierras. We updated or generated a total of 20 tree-ring chronologies from bigcone Douglas-fir, blue oak, and foxtail pine. We developed two reconstruction models for each gage: a ‘most skillful’ model from 1426 to 2016, and a longer model that extends to the early 1100s. Significant dry and wet periods were identified using runs analysis and moving averages of varying window lengths. The longer reconstructions reveal that the mid-1100s was a period of persistent drought, while both reconstruction models highlight droughts in the mid-1400s late 1500s and mid-1600s. The recent drought (2012 – 2016) ranks as the driest consecutive 5-year period among the most skillful reconstructions, while 2012 – 2015 is the driest 4-year period in many of the longest reconstructions. Our reconstructions identify shifts between wet and dry conditions in the mid 1500s and mid 1700s, and increasing frequency of wet years in the instrumental period. A subset of past droughts in southern California coincided with drought in northern California and the Colorado River.