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Title: Implications of Detection Methods on Characterizing Atmospheric River Contribution to Seasonal Snowfall Across Sierra Nevada, USA: Atmospheric River Detection and Snowfall
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Publication Date:
Journal Name:
Geophysical Research Letters
Page Range or eLocation-ID:
10,445 to 10,453
DOI PREFIX: 10.1029
Sponsoring Org:
National Science Foundation
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  1. Abstract

    We characterize the sensitivity of atmospheric river (AR)‐derived seasonal snowfall estimates to their atmospheric reanalysis‐based detection over Sierra Nevada, USA. We use an independent snow data set and the ARs identified with a single detection method applied to multiple atmospheric reanalyses of varying horizontal resolutions, to evaluate orographic relationships and contributions of individual ARs to the seasonal cumulative snowfall (CS). Spatial resolution differences have relatively minor effects on the number of ARs diagnosed, with higher‐resolution data sets identifying four more AR days per year, on average, during the 1985–2015 winters. However, this can lead to ~10% difference in AR attribution to the mean domain‐wide seasonal CS and differences up to 47% snowfall attribution at the seasonal scale. We show that identifying snow‐bearing ARs provides more information about the seasonal CS than simply knowing how many ARs occurred. Overall, we find that higher‐resolution atmospheric reanalyses imply greater attribution of seasonal CS to ARs.

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