Classification of Northern Hemisphere stratospheric ozone and water vapor profiles by meteorological regime
- ISSN: 1680-7324
- DOI: 10.5194/acp-9-5989-2009
The subtropical and polar upper troposphere fronts and the polar vortex\nserve as the boundaries to divide the Northern Hemisphere into four\nmeteorological regimes. These regimes are defined as (1) the arctic\nregime - within the polar vortex, (2) the polar regime - between the\npolar front and the polar vortex, or when the latter is not present, the\npole, (3) the midlatitude regime - between the subtropical and polar\nfronts, and (4) the tropical regime - between the equator and the\nsubtropical front.\nData from the Halogen Occultation Experiment (HALOE) and the\nStratospheric Aerosol and Gas Experiment II (SAGE II) were used to show\nthat within each meteorological regime, ozone and water profiles are\ncharacterized by unique ozonepause and hygropause heights. Daily\nmeasurements and seven-year (1997-2003) monthly climatologies showed\nthat, within each meteorological regime, both constituents exhibited\ndistinct profile shapes from the tropopause up to approximately 20 km.\nThis distinction was most pronounced in the winter and spring months,\nand weak in the summer and fall. Despite differences in retrieval\ntechniques and sampling between the SAGE and HALOE instruments, the\nseven-year monthly climatologies calculated for each regime agreed well\nfor both species below similar to 22 km.\nGiven that profiles of ozone and water vapor exhibit unique profiles\nshapes within each regime in the UTLS, trends in this region will\ntherefore be the result of both changes within each meteorological\nregime, and changes in the relative contribution of each regime to a\ngiven zonal band over time.