Much of the epic rainfall that flooded California in early 2017 flowed into the region via a stream of water vapor in the sky. These atmospheric rivers—sometimes known as the Pineapple Express—transport large quantities of water poleward from the tropics. Now, new UGA research shows that these phenomena can wreak havoc in the Southeast as well.
Geography and atmospheric sciences researchers provide the first detailed climatological analysis of southeastern atmospheric rivers in a new study published in the International Journal of Climatology. “Our study shows that they are more common than we thought in the Southeast,” said J. Marshall Shepherd, Georgia Athletic Association Distinguished Professor and director of UGA’s atmospheric sciences program.
The research emerged from a graduate seminar on atmospheric rivers developed by UGA Distinguished Research Professor of Geography Thomas Mote.
“We found that atmospheric rivers in the Southeast were fairly common and most prevalent during the winter,” said Neil Debbage, doctoral candidate in the UGA department of geography and first author on the study. “However, the specific number and nature of atmospheric rivers differed between various sub-regions of the Southeast.”
Major flooding in Nashville in 2010, for example, was associated with atmospheric river activity.
But not all atmospheric rivers cause damage, as many are weak and can provide much-needed precipitation.
As Debbage said, “A better understanding of when atmospheric river events occur in the Southeast, their basic characteristics, and the weather patterns conducive for their development will lead to improved forecasting and community awareness.”
