Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling

Contributions of Extreme and Non‐Extreme Precipitation to California Precipitation Seasonality Changes Under Warming

TitleContributions of Extreme and Non‐Extreme Precipitation to California Precipitation Seasonality Changes Under Warming
Publication TypeJournal Article
Year of Publication2019
AuthorsDong, Lu, L. Leung Ruby, Lu Jian, and Gao Yang
JournalGeophysical Research Letters
Volume46
Number22
Pages13470-13478
Abstract / Summary

Changes in seasonality of extreme precipitation have important implications for flood and fire hazards and water resources. Here we explore the contributions of extreme and non‐extreme precipitation in the sharpened wet season in California under warming and the underlying mechanisms. Modeling evidence shows that increased extreme precipitation due to enhanced extreme intensity and more extreme days dominates the wetter winter, while decreased non‐extreme precipitation due to fewer wet days induces the dryer spring and fall. Moisture budget analysis indicates that increased moisture dominates the extreme precipitation increase in winter, while weakened circulation offsets the moisture increase, resulting in no changes in spring and fall. The sharpened seasonal cycle of extreme precipitation via both dynamic and thermodynamic effects is consistent with the seasonality changes in atmospheric river days and is mainly attributed to the seasonality changes in the number of extreme days rather than the intensity during extreme days.

URLhttp://dx.doi.org/10.1029/2019gl084225
DOI10.1029/2019gl084225
Journal: Geophysical Research Letters
Year of Publication: 2019
Volume: 46
Number: 22
Pages: 13470-13478
Publication Date: 11/2019

Changes in seasonality of extreme precipitation have important implications for flood and fire hazards and water resources. Here we explore the contributions of extreme and non‐extreme precipitation in the sharpened wet season in California under warming and the underlying mechanisms. Modeling evidence shows that increased extreme precipitation due to enhanced extreme intensity and more extreme days dominates the wetter winter, while decreased non‐extreme precipitation due to fewer wet days induces the dryer spring and fall. Moisture budget analysis indicates that increased moisture dominates the extreme precipitation increase in winter, while weakened circulation offsets the moisture increase, resulting in no changes in spring and fall. The sharpened seasonal cycle of extreme precipitation via both dynamic and thermodynamic effects is consistent with the seasonality changes in atmospheric river days and is mainly attributed to the seasonality changes in the number of extreme days rather than the intensity during extreme days.

DOI: 10.1029/2019gl084225
Citation:
Dong, L, L Leung, J Lu, and Y Gao.  2019.  "Contributions of Extreme and Non‐Extreme Precipitation to California Precipitation Seasonality Changes Under Warming."  Geophysical Research Letters 46(22): 13470-13478.  https://doi.org/10.1029/2019gl084225.