UNC-led team to study California's high agricultural productivity despite years of drought
September 20, 2016
Despite years of crippling drought, California continues to set records with farm-grown food production. But with water supply, the agricultural industry and energy production all inextricably linked, is this escalating productivity an outlier or something that can be sustained?
These questions and more are at the root of a new, nearly $3 million National Science Foundation (NSF)-funded study that will be led by the University of North Carolina’s Gregory Characklis, PhD, professor of environmental sciences and engineering at UNC’s Gillings School of Global Public Health. Characklis is also director of the UNC Institute for the Environment’s Center for Watershed Science and Management.
The grant is part of NSF’s “Innovations at the Nexus of Food-Energy-Water” and is the second NSF award to Characklis in the last two years. In 2014, a team led by Characklis received a $2.2 million grant from the joint NSF and U.S. Department of Agriculture (USDA) program, “Water Sustainability and Climate,” designed to develop innovative strategies for sustainably meeting future water demands in North Carolina and across the Southeastern United States.
This most recent grant, however, will use the California drought as the basis for a case study.
“While the focus is on California,” Characklis said, “the data that will be collected and the modeling systems that our team will develop should ultimately bring benefits to many states and regions that suffer from drought in the future.”
The crux of the new study is the interdependency of the systems that supply food, energy and water. For example, in California, food production is centered in the state’s Central Valley region. In normal years, farmers draw rainfall and snow melt from the Sierra Nevada mountains. However, during drought periods, farmers must irrigate their fields using pumped ground water.
The use of these pumps can cause farmers’ electrical demands to increase by as much as 33 percent in the summer when urban electricity demands also rise. This comes at the same time that reduced rainfall and snowpack runoff reduces California’s hydroelectric power generation, which makes up roughly 20 percent of its overall electrical capacity.
This means that electric utilities must increase reliance on more expensive power generating fuels, typically natural gas, leading to higher electricity prices. The result is that farmers use much more electricity when prices are at their highest, leading to potential economic distress for the farms and higher food prices for consumers.
“The human and natural systems that provide society with food, energy and water are tightly linked, so a disruption in one invariably impacts the others,” Characklis said. “This research will provide us an opportunity to develop an improved understanding of these systems and ultimately develop innovative management strategies using tools from science, engineering and economics.”
The study will include work by two UNC faculty members – Jordan Kern, PhD, research assistant professor at the UNC Institute for the Environment and Tamlin Pavelsky, PhD, associate professor of geology. Scientists from the University of California-Davis and Cornell University are also part of Characklis’ research team.
“Solutions to our most pressing environmental challenges are invariably interdisciplinary, and this is particularly true of water,” Characklis said. “NSF continues to encourage large-scale efforts to explore new problem-solving approaches that cross disciplinary boundaries, and UNC should be well positioned to take advantage of these.”
The $2.95 million NSF Innovations at the Nexus of Food-Energy-Water grant will span three years.