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Title: On the role of Rossby wave breaking in the quasi‐biennial modulation of the stratospheric polar vortex during boreal winter
Abstract Key Findings

• Rossby wave breaking (RWB) is enhanced in the height regions where the zero‐wind line is shifted into the winter hemisphere and where the QBO‐induced meridional circulation is directed toward the winter pole

• Polar vortex responses differ in terms of the height location of RWB, zonal wave‐number‐dependent disturbances and seasonal development

• Significant increase in wave‐1 occurs when the QBO is in its easterly phase

• A cumulative effect of RWB results in enhanced wave forcing of zonal wave‐numbers 2 and 3 during westerly QBO, which manifests in a sign reversal of the Holton–Tan effect in late winter.

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Award ID(s):
Publication Date:
Journal Name:
Quarterly Journal of the Royal Meteorological Society
Page Range or eLocation-ID:
p. 1939-1959
Wiley Blackwell (John Wiley & Sons)
Sponsoring Org:
National Science Foundation
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