Drought impacts to water footprints and virtual water transfers of the Central Valley of California

Abstract

The Central Valley of California is one of the most productive agricultural locations in the world, which is made possible by a complex and vast irrigation system. Beginning in 2012, California endured one of the worst droughts in its history. Local impacts of the drought have been evaluated, but it is not yet well understood how the drought reverberated through the global food system. Here we quantify drought impacts to the water footprint (WF) of agricultural production and virtual water transfers (VWT) from the Central Valley of California. To do this, we utilize high‐resolution spatial and temporal data sets and a crop model from predrought conditions (2011) through 3 years of exceptional drought (2012–2014). Despite a 12% reduction in harvested area, the WF of agricultural production in the Central Valley increased by 3%. This was due to greater crop water requirements from higher temperatures and a shift to more water‐intensive orchard and vine crops. The groundwater WF increased from 7.00 km3 in 2011 to 13.63 km3 in 2014, predominantly in the Tulare Basin. Transfers of food commodities declined by 1% during the drought, yet total VWT increased by 3% (0.51 km3). From 2011 to 2014, groundwater VWT increased by 3.42 km3, offsetting the 0.94 km3 reduction in green VWT and the 1.96 km3 decrease in surface VWT. During the drought, local and global consumers nearly doubled their reliance on the Central Valley Aquifer. These results indicate that drought may strengthen the telecoupling between groundwater withdrawals and distant consumers of agricultural commodities.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 01, 2017
Source ID
10.1002/2016wr020251

Entities

People

  • Landon Marston
  • Megan Konar

Organizations

  • Kansas State University
  • National Science Foundation
  • United States Department of Defense
  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Environmental science

Readers

  • Astronomy and Astrophysics.
  • Environmental Engineering
  • Forest Ecology