Premium
Characterizing the influence of atmospheric river orientation and intensity on precipitation distributions over North Coastal California
Author(s) -
Hecht Chad W.,
Cordeira Jason M.
Publication year - 2017
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2017gl074179
Subject(s) - precipitation , mesoscale meteorology , environmental science , orography , forcing (mathematics) , water vapor , watershed , climatology , orographic lift , atmospheric sciences , meteorology , geology , geography , machine learning , computer science
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.