Droughts May Behave Like Dominos: Stanford Study

PALO ALTO, CA — As the United States moves into the summer months, a recent study examines whether a drought in California can be linked to one in the Midwest. The Stanford-led study published in Geophysical Research Letters finds that regions may fall victim to water scarcity like dominos across the nation, the university news service reported.

“We know droughts can travel thousands of miles across continents, but it has not been clear exactly how,” said lead author Julio E. Herrera Estrada, a postdoctoral scholar with the Stanford Water in the West program and the Stanford Department of Earth System Science.

Droughts occur when a lack of precipitation causes a water shortage. Continents receive most of their precipitation from water vapor transported by wind from other land masses and oceans. Moisture also evaporates from a region and falls in the same area – a process known as recycling, the news service added.

In this study, researchers looked at how decreased moisture from this process amplified the 2012 drought in the Midwest, which resulted in losses of over $33 billion.

Like most of the nation, the Midwest relies on moisture imported from other regions. When a drought occurred in the western United States that same year, it resulted in less evaporation and drier air.

The study found that the Midwest eventually recovered from drought when more moisture was imported directly from the ocean. The cycle restarts the process in the region.

“We show that multiple droughts over a continent may not necessarily be a coincidence,” Herrera Estrada said.

As the country faces more intense climactic events, understanding how droughts form and move may prove to be increasingly important.

“It will also be crucial to take a regional approach to drought risk management and facilitate coordination between upwind and downwind communities to reduce the severity and impacts of future droughts,” Herrera Estrada concluded. “In many instances, this will require international cooperation.”

Read the full Stanford article here.