Dynamic Synoptic Eddy Feedbacks Contributing to Maintenance and Propagation of Intraseasonal NAO
نویسندگان
چکیده
This study examines the dynamic feedbacks generated from synoptic eddies that contribute to maintenance and propagation of intraseasonal North Atlantic Oscillation (ISNAO) which has significant 20?60-day variability features clearly westward slightly northward propagations. The ISNAO-related eddy-vorticity fluxes induced forcing positive in-phase feedback upstream ISNAO. Due accumulated shearing effect ISNAO zonal wind anomalies, eddy structures can be statistically changed in a zonally titling way, forms quadrupole patterns anomalous structure further generates meridional by multiplying basic velocity vorticity. These diverge pattern area its west mainly induce phase with ISNAO, where maintains shift contributes propagations
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ژورنال
عنوان ژورنال: Geophysical Research Letters
سال: 2022
ISSN: ['1944-8007', '0094-8276']
DOI: https://doi.org/10.1029/2021gl096508