Thompson A.M.,Pennsylvania State University |
Miller S.K.,Pennsylvania State University |
Tilmes S.,U.S. National Center for Atmospheric Research |
Kollonige D.W.,Pennsylvania State University |
And 29 more authors.
Journal of Geophysical Research: Atmospheres | Year: 2012
We present a regional and seasonal climatology of SHADOZ ozone profiles in the troposphere and tropical tropopause layer (TTL) based on measurements taken during the first five years of Aura, 2005-2009, when new stations joined the network at Hanoi, Vietnam; Hilo, Hawaii; Alajuela/Heredia, Costa Rica; Cotonou, Benin. In all, 15 stations operated during that period. A west-to-east progression of decreasing convective influence and increasing pollution leads to distinct tropospheric ozone profiles in three regions: (1) western Pacific/eastern Indian Ocean; (2) equatorial Americas (San Cristóbal, Alajuela, Paramaribo); (3) Atlantic and Africa. Comparisons in total ozone column from soundings, the Ozone Monitoring Instrument (OMI, on Aura, 2004-) satellite and ground-based instrumentation are presented. Most stations show better agreement with OMI than they did for EP/TOMS comparisons (1998-2004; Earth-Probe/Total Ozone Mapping Spectrometer), partly due to a revised above-burst ozone climatology. Possible station biases in the stratospheric segment of the ozone measurement noted in the first 7 years of SHADOZ ozone profiles are re-examined. High stratospheric bias observed during the TOMS period appears to persist at one station. Comparisons of SHADOZ tropospheric ozone and the daily Trajectory-enhanced Tropospheric Ozone Residual (TTOR) product (based on OMI/MLS) show that the satellite-derived column amount averages 25% low. Correlations between TTOR and the SHADOZ sondes are quite good (typical r2 = 0.5-0.8), however, which may account for why some published residual-based OMI products capture tropospheric interannual variability fairly realistically. On the other hand, no clear explanations emerge for why TTOR-sonde discrepancies vary over a wide range at most SHADOZ sites. © 2012. American Geophysical Union. All Rights Reserved.
Stickler A.,ETH Zurich |
Grant A.N.,ETH Zurich |
Ewen T.,ETH Zurich |
Ross T.F.,National Oceanic and Atmospheric Administration |
And 12 more authors.
Bulletin of the American Meteorological Society | Year: 2010
A new dataset, Comprehensive Historical Upper-Air Network (CHUAN), has been developed as a systematic compilation of the different sources in only three standard formats. The first includes the data that come on pressure levels from all platforms except radiosondes, second for the data on geometrical altitude levels, and third with four additional pressure levels for the radiosonde data. The pilot balloon data are given predominantly on geometrical altitude levels above mean sea level, but some observations are given on levels above ground level or on pressure levels. The radiosonde data are given solely on pressure (p) levels whereas the kite, aircraft, and registering balloon data are either on pressure or geometrical altitude levels. CHUAN data have been reformatted into three simple ASCII formats, one each for pressure level and geometrical altitude level data, and one with four additional pressure levels for the radiosonde data.