Enhanced hydrological extremes in the western United States under global warming through the lens of water vapor wave activity

Journal Article · Mon Apr 23 04:00:00 EDT 2018 · npj Climate and Atmospheric Science

DOI:https://doi.org/10.1038/s41612-018-0017-9· OSTI ID:1437541

Lu, Jian; Xue, Daokai; Gao, Yang; Chen, Gang; Leung, L. R.; Staten, P.

Understanding how regional hydrological extremes would respond to warming is a grand challenge to the community of climate change research. To address this challenge, we construct an analysis framework based on column integrated water vapor (CWV) wave activity to diagnose the wave component of the hydrological cycle that contributes to hydrological extremes. By applying the analysis to the historical and future climate projections from the CMIP5 models, we found that the wet-versus-dry disparity of daily net precipitation along a zonal band can increase at a super Clausius-Clapeyron rate due to the enhanced stirring length of wave activity at the poleward flank of the mean storm track. The local variant of CWV wave activity reveals the unique characteristics of atmospheric rivers (ARs) in terms of their transport function, enhanced mixing and hydrological cycling rate (HC). Under RCP8.5, the local moist wave activity increases by ~40% over the northeastern Pacific by the end of the 21st century, indicating more ARs hitting the west coast, giving rise to a ~20% increase in the related hydrological extremes - $ despite a weakening of the local HC.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1437541
• Report Number(s): PNNL-SA-126188; KP1703010
• Journal Information: npj Climate and Atmospheric Science, Journal Name: npj Climate and Atmospheric Science Journal Issue: 1 Vol. 1; ISSN 2397-3722
• Country of Publication: United States
• Language: English