Student Posters Repository

Atmospheric river (AR) impacts on hydrologic extremes are greater when an AR event follows closely on the heels of another or several occur in sequence. This study uses coastal Atmospheric River Observatory measurements and Modern-Era Retrospective analysis for Research and Applications, Version 2 reanalysis from water years (WY) 2005 - 2017 to examine 228 landfalling atmospheric river events (ARs) at Bodega Bay (BBY) in Northern California. During the winter of 2016-2017, 34 ARs hit California’s Russian River basin, many in quick succession. (An “AR event” is a period of continuous AR conditions observed at BBY by the ARO.) This provided motivation to develop a definition of “atmospheric river families,” to describe their characteristics and to assess their predictability. An AR family is identified when two AR events are separated by < 120 hours, yet often include more than two AR events in long duration AR families. Using this definition, a catalog of AR families was created for BBY. Out of the 228 AR events observed, 109 (i.e., almost 50%) initiated an AR family. Composites of AR families show general characteristics of these successive storms, which differ significantly from individual events.