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Title: Evolution of microwave limb sounder ozone and the polar vortex during winter

Journal Article · · Journal of Geophysical Research
DOI:https://doi.org/10.1029/94JD02823· OSTI ID:57391
; ; ;  [1]
  1. Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA (United States)

The evolution of polar ozone observed by the Upper Atmosphere Research Satellite (UARS) Microwave Limb Sounder (MLS) is described for the northern hemisphere (NH) winters of 1991/1992, 1992/1993, and 1993/1994 and the southern hemisphere (SH) winters of 1992 and 1993. Imterannual and interhemispheric variability in polar ozone evolution are closely related to differences in the polar vortex and to the frequency, duration and strength of stratospheric sudden warmings. Ozone in the midstratospheric vortices increases during the winter, with largest increases associated with stratospheric warmings and a much larger increase in the NH than in the SH. A smaller NH increase was observed in 1993/1994, when the middle stratospheric vortex was stronger. During strong stratospheric warmings in the NH, the upper stratospheric vortex may be so much eroded that it presents little barrier to poleward transport; in contrast, the SH vortex remains strong throughout the stratosphere during wintertime warmings, and ozone increases only below the mixing ratio peak, due to enhanced diabatic descent. Ozone mixing ratios decrease rapidly in the lower stratosphere in both SH late winters, as expected from chemical destruction due to enhanced reactive chlorine. The interplay between dynamics and chemistry is more complex in the NH lower stratosphere and interannual variability is greater. Evidence has previously been shown for chemical ozone destruction in the 1991/1992 and 1992/1993 winters.

Research Organization:
California Institute of Technology (CalTech), Pasadena, CA (United States). Jet Propulsion Lab. (JPL)
OSTI ID:
57391
Journal Information:
Journal of Geophysical Research, Vol. 100, Issue D2; Other Information: PBD: Feb 1995
Country of Publication:
United States
Language:
English