Local Finite-Amplitude Wave Activity as an Objective Diagnostic of Midlatitude Extreme Weather

TitleLocal Finite-Amplitude Wave Activity as an Objective Diagnostic of Midlatitude Extreme Weather
Publication TypeJournal Article
Year of Publication2015
JournalGeophysical Research Letters
Volume42
Number24
Pages10952-10960
Date Published12/2015
Abstract / Summary

Midlatitude extreme weather events are responsible for a large part of climate-related damage, yet our understanding of these extreme events is limited, partly due to the lack of a theoretical basis for midlatitude extreme weather. In this letter, the local finite-amplitude wave activity (LWA) of Huang and Nakamura (2015) is introduced as a diagnostic of the 500 hPa geopotential height for characterizing midlatitude weather events. It is found that the LWA climatology and its variability associated with the Arctic Oscillation agree broadly with the previously reported blocking frequency in the literature. There is a strong seasonal and spatial dependence in the trends of LWA in recent decades. While there is no observational evidence for a hemispheric-scale increase in wave amplitude, robust trends in wave activity can be identified at the regional scales, with important implications for regional climate change.

URLhttp://onlinelibrary.wiley.com/wol1/doi/10.1002/2015GL066959/full
DOI10.1002/2015GL066959
Journal: Geophysical Research Letters
Year of Publication: 2015
Volume: 42
Number: 24
Pages: 10952-10960
Date Published: 12/2015

Midlatitude extreme weather events are responsible for a large part of climate-related damage, yet our understanding of these extreme events is limited, partly due to the lack of a theoretical basis for midlatitude extreme weather. In this letter, the local finite-amplitude wave activity (LWA) of Huang and Nakamura (2015) is introduced as a diagnostic of the 500 hPa geopotential height for characterizing midlatitude weather events. It is found that the LWA climatology and its variability associated with the Arctic Oscillation agree broadly with the previously reported blocking frequency in the literature. There is a strong seasonal and spatial dependence in the trends of LWA in recent decades. While there is no observational evidence for a hemispheric-scale increase in wave amplitude, robust trends in wave activity can be identified at the regional scales, with important implications for regional climate change.

DOI: 10.1002/2015GL066959
Citation:
Chen, G, J Lu, DA Burrows, and LR Leung.  2015.  "Local Finite-Amplitude Wave Activity as an Objective Diagnostic of Midlatitude Extreme Weather."  Geophysical Research Letters 42(24): 10952-10960.  https://doi.org/10.1002/2015GL066959.