Jim Angells contributions to understanding the QBO Jim

Jim Angell’s contributions to understanding the QBO

Jim Angell’s contributions to understanding the QBO

Jim Angell’s contributions to understanding the QBO !

discovery of QBO

discovery of QBO Angell and Korshover 1962, 1963

Meridional structure of QBO from Angell and Korshover, 1963

Equatorial QBO derived from radiosondes and rockets Baldwin et al. , 2001

Schematic of global QBO Baldwin et al. , 2001

Angell and Korshover (1964) coin the term ‘Quasi-Biennial Oscillation’

Naming the QBO was not easy. . . kind-of biennial oscillation almost biennial oscillation not quite biennial oscillation somewhat biennial oscillation quasi-biennial oscillation

50 h. Pa temps note out-of-phase between tropics and midlats

QBO temperature signal in lower stratosphere derived from regression with MSU 4

Snapshot of temperatures and meridional circulation associated with the QBO February 1994 out-of-phase vertical structure note extension into winter midlats

Equatorial waves and the QBO

midlats power spectra subtropics strong peak at 10 -15 days

Idealized wave-mean flow interaction in QBO Kelvin waves only propagate in background easterly winds

Kelvin waves observed during easterly QBO winds zonal wind eddy power spectra

QBO effects on ‘centers of action’

Surface signal of QBO Baldwin et al. , 2001

Holton-Tan effect

Holton-Tan effect (composited QBO E-W) observations 1964 -1996 SKYHI simulation (48 years)

Meridional structure of QBO from Angell and Korshover, 1963 evidence of Holton-Tan effect

Ozone QBO

out of phase between tropics and midlats

Column ozone from TOMS total interannual variability QBO component

Vertical structure of ozone QBO at equator 2 -cell structure

QBO signal in nitrogen dioxide (NO 2)

QBO and stratospheric water vapor

stratospheric water vapor tropical tropopause temperature

QBO from variations in stratospheric water vapor HALOE satellite data, 1991 -2003 Deseasonalized anomalies

Vertical propagation of QBO anomalies (interannual ‘tape recorder’)

Stratospheric H 2 O anomalies are consistent with tropical tropopause temperature changes HALOE H 2 O anomalies tropical tropopause temperature anomalies

Jim Angell’s contributions span all aspects of the QBO. * global structure and propagation * ozone * equatorial waves * coupling with troposphere * tropopause and stratospheric H 2 O Much of this original research is still relevant today!

QBO Happy Birthday Jim!