Variability of the global tropopause derived from radiosondes and GPS satellite observations

Statistics of the global tropopause are examined based on historical radiosonde data, plus high vertical resolution GPS radio occultation temperature measurements. Variability of tropopause height on daily and seasonal time scales is examined in detail, and good agreement is found in comparisons of statistics based on radiosondes and GPS data. Double tropopauses are found to occur frequently over extratropics of both hemispheres, preferentially during winter, and GPS data provide a global climatology of double tropopause occurrences. Radiosonde data are used to study long-term variability of the tropopause, in particular to document decadal-scale changes in tropopause height over the globe.