Characterizing the influence of atmospheric river orientation and intensity on precipitation distributions over North Coastal California

Abstract

Atmospheric rivers (ARs) are long (>2000 km) and narrow (500–1000 km) corridors of enhanced vertically integrated water vapor and enhanced integrated water vapor transport (IVT) that are responsible for a majority of global poleward moisture transport and can result in extreme orographic precipitation. Observational evidence suggests that ARs within different synoptic‐scale flow regimes may contain different water vapor source regions, orientations, and intensities and may result in different precipitation distributions. This study uses k‐means clustering to objectively identify different orientations and intensities of ARs that make landfall over the California Russian River watershed. The ARs with different orientations and intensities occur within different synoptic‐scale flow patterns in association with variability in IVT direction and quasi‐geostrophic forcing for ascent and lead to different precipitation distributions over the Russian River watershed. These differences suggest that both mesoscale upslope moisture flux and synoptic‐scale forcing for ascent are important factors in modulating precipitation distributions during landfalling ARs.

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 09, 2017
Source ID
10.1002/2017gl074179

Entities

People

  • Chad W. Hecht
  • Jason M. Cordeira

Organizations

  • Plymouth State University
  • Scripps Institution of Oceanography
  • United States Army Corps of Engineers

Tags

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology
  • Coastal and Marine Engineering/Sediment Transport/Hydraulic Engineering
  • Molecular Photonics/Laser Physics