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TOMS Trends vs Latitude and Season  

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Observed trends in ozone total column reported from the Total Ozone Mapping Spectrometry (TOMS) using observations obtained over the past 11 years. Recent improvements in the data analysis have led to a technique for determining and removing drift in the calibration such that the data at the end of 11-1/2 years are accurate to ±1.3% (2σ) relative to the data at the beginning of the record.

II. Scientific Questions 

While there are literally dozens of specific questions that must be dealt with quantitatively, for the sake of coherence they can be categorized as follows:
Question 1. How do the meteorological (pressure, temperature, wind) fields, radiation (UV, VIS, IR) fields, vertically stratified tracer (N2O, CH4, CFC-11) fields, and ozone, water vapor, and aerosol fields evolve during setup, maintenance, and breakup of the vortex?

The thrust of this question is to define the structure of the stratosphere poleward of 40° latitude between altitudes of 10 and 30 km.

• When does diabatic cooling begin to distort the “normal“ summertime tracer fields? What is the temporal evolution of potential temperature and potential vorticity fields as the polar jet develops?

• To what degree is there stratospheric — tropospheric exchange along isentropic surfaces?

• To what extent is there exchange between inner and outer vortex air during the lifetime of the vortex?

• What is the origin of air that occupies the core of the vortex?

• Do rates of subsidence reflected in distortions on the tracer fields match subsidence rates inferred for diabatic cooling rates determined from observations of radiance divergence?

• To what extent is the vortex stabilized by ozone loss from the core?

• What is the latitude and altitude dependence of the balance among diabatic heating, heat transport by motion, and local temperature changes?

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