Two new methods for deriving tropospheric column ozone from TOMS measurements: Assimilated UARS MLS/HALOE and convective‐cloud differential techniques

摘要: This study introduces two new approaches for determining tropospheric column ozone from satellite data. In the first method, stratospheric is derived by combining Upper Atmosphere Research Satellite (UARS) halogen occultation experiment (HALOE) and microwave limb sounder (MLS) measurements. Tropospheric then obtained subtracting these amounts total column. Total in this include retrievals Nimbus 7 (November 1978 to May 1993) Earth probe (July 1996 present) mapping spectrometer (TOMS). Data HALOE are used method extend vertical span of MLS (highest pressure level 46 hPa) using simple regression. assimilation enables high-resolution daily maps which not possible solar measurements alone, such as or Stratospheric Aerosols Gas Experiment (SAGE). We also examine another promising technique that yields directly TOMS high-density footprint regions high convective clouds. define cloud differential (CCD) technique. The CCD shown provide long time series (essentially late dominated persistent tropopause-level clouds, maritime tropical Pacific within near midlatitude continental landmasses. our MLS/HALOE methods we limit analyses latitudes. Separation eastern tropics January 1979 December 1997 shows dominant interannual variability quasi-biennial oscillation (QBO), whereas it driven El Nino events. For validation purposes, both assimilated UARS results compared with ozonesonde data several southern stations. Despite all three being distinctly different sampling technique, show good qualitative agreement.