Well Depth in California, 1980-2018

Source: Amid Climate-Linked Drought, Farmers Turn to New Water Sources. Those Are Drying Up Too, Forbes, July 2019

July 2019 was the hottest recorded month in human history. August was the second hottest.  As climate change further raises the temperature on already-warm summers, the effect on crop production could be significant. In the United States, farmers are already beginning to adapt to this new reality by ramping up irrigation. This could become a problem as their adaptation to heat only exacerbates another major consequence of climate change—water scarcity.

Fiona Burlig, an assistant professor at Harris Public Policy, is analyzing this challenge using California as a case study.  California is an ideal setting for studying agriculture, as it generates more than 13 percent of the country’s total crop value. It has also recently experienced a series of droughts.

What are California farmers doing to cope during periods of drought? While surface water use is restricted during droughts, groundwater use is not. As a result, during these drought periods, farmers are increasing their reliance on groundwater, and digging deeper wells. As wells become deeper, the price of a gallon of groundwater rises. Because water is an essential input into California crops, these price increases have the potential to raise food prices across the country. In the nearer term, these results highlight the need to consider unintended consequences of water regulation, and address both surface and groundwater use.

Short: As climate change makes already-warm summers even hotter, farmers are grappling with how to keep their crops healthy. Increasingly, they are turning to irrigation, which could become a problem as their adaptation to heat exacerbates another major consequence of climate change—water scarcity. Using California as a case study, Fiona Burlig, an assistant professor at Harris Public Policy, found that when farmers’ surface water runs out, they are turning to groundwater—digging deeper and deeper wells to get the water they need. As wells become deeper, the price of a gallon of groundwater rises. Because water is an essential input into California crops, these price increases have the potential to raise food prices across the country.