MISSION: WATER 28 HEADLINE SURFACE WATER Understanding Atmospheric Rivers The U.S. National Oceanic & Atmospheric Administration (NOAA) defines atmospheric rivers as narrow regions in the atmosphere that are responsible for most of the horizontal transport of water vapor outside of the tropics. These events are responsible for 30-50% of annual precipitation in the west coast of the United States and can transport up to 15 times the average flow of the Mississippi river to a region. It’s all about the data. When licensed professional surveyors and engineers from eTrac, SurvTech Solutions, and Brunswick Engineering needed a LiDAR enabled UAV, they leveraged the NEXUS 800. The acquired data were expeditiously processed and disseminated to the mitigation teams for action within a span of 36 hours—an incredible feat. More importantly, the data set acquired by the NEXUS 800 agreed to within 5.5 centimeters of LiDAR data that overlapped in other areas where traditional survey crews had previously collected data. An aerial view of Lake Oroville at 83 percent of capacity or 104 percent of historical average, while the California Department of Water Resources released water at 35,000 cubic feet per second (cfs) from the flood control spillway. Photo taken on April 21, 2017. Kelly M. Grow, California Department of Water Learn more about atmospheric rivers at: esrl.noaa.gov/psd/atmrivers