Validation of ACE and OSIRIS ozone and NO2 measurements using ground-based instruments at 80 degrees N
Artikel i vetenskaplig tidskrift, 2012

The Optical Spectrograph and Infra-Red Imager System (OSIRIS) and the Atmospheric Chemistry Experiment (ACE) have been taking measurements from space since 2001 and 2003, respectively. This paper presents intercomparisons between ozone and NO2 measured by the ACE and OSIRIS satellite instruments and by ground-based instruments at the Polar Environment Atmospheric Research Laboratory (PEARL), which is located at Eureka, Canada (80A degrees N, 86A degrees W) and is operated by the Canadian Network for the Detection of Atmospheric Change (CANDAC). The ground-based instruments included in this study are four zenith-sky differential optical absorption spectroscopy (DOAS) instruments, one Bruker Fourier transform infrared spectrometer (FTIR) and four Brewer spectrophotometers. Ozone total columns measured by the DOAS instruments were retrieved using new Network for the Detection of Atmospheric Composition Change (NDACC) guidelines and agree to within 3.2%. The DOAS ozone columns agree with the Brewer spectrophotometers with mean relative differences that are smaller than 1.5%. This suggests that for these instruments the new NDACC data guidelines were successful in producing a homogenous and accurate ozone dataset at 80A degrees N. Satellite 14-52 km ozone and 17-40 km NO2 partial columns within 500 km of PEARL were calculated for ACE-FTS Version 2.2 (v2.2) plus updates, ACE-FTS v3.0, ACE-MAESTRO (Measurements of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) v1.2 and OSIRIS SaskMART v5.0x ozone and Optimal Estimation v3.0 NO2 data products. The new ACE-FTS v3.0 and the validated ACE-FTS v2.2 partial columns are nearly identical, with mean relative differences of 0.0 +/- 0.2% and -0.2 +/- 0.1% for v2.2 minus v3.0 ozone and NO2, respectively. Ozone columns were constructed from 14-52 km satellite and 0-14 km ozonesonde partial columns and compared with the ground-based total column measurements. The satellite-plus-sonde measurements agree with the ground-based ozone total columns with mean relative differences of 0.1-7.3%. For NO2, partial columns from 17 km upward were scaled to noon using a photochemical model. Mean relative differences between OSIRIS, ACE-FTS and ground-based NO2 measurements do not exceed 20%. ACE-MAESTRO measures more NO2 than the other instruments, with mean relative differences of 25-52%. Seasonal variation in the differences between NO2 partial columns is observed, suggesting that there are systematic errors in the measurements and/or the photochemical model corrections. For ozone spring-time measurements, additional coincidence criteria based on stratospheric temperature and the location of the polar vortex were found to improve agreement between some of the instruments. For ACE-FTS v2.2 minus Bruker FTIR, the 2007-2009 spring-time mean relative difference improved from -5.0 +/- 0.4% to -3.1 +/- 0.8% with the dynamical selection criteria. This was the largest improvement, likely because both instruments measure direct sunlight and therefore have well-characterized lines-of-sight compared with scattered sunlight measurements. For NO2, the addition of a +/- 1A degrees latitude coincidence criterion improved spring-time intercomparison results, likely due to the sharp latitudinal gradient of NO2 during polar sunrise. The differences between satellite and ground-based measurements do not show any obvious trends over the missions, indicating that both the ACE and OSIRIS instruments continue to perform well.

ugatchev ns


radiative-transfer models



journal of geophysical research-atmospheres

mmereau jp



stratospheric no2






geophysical research letters

chemistry experiment ace

absorption cross-sections





C. Adams

University of Toronto

K. Strong

University of Toronto

R. L. Batchelor

The Earth and Sun Systems Laboratory

University of Toronto

P. F. Bernath

Old Dominion University

University of Waterloo

University of York

Samuel Brohede

Chalmers, Rymd- och geovetenskap, Global miljömätteknik och modellering

C. Boone

University of Waterloo

D. Degenstein

University of Saskatchewan

W.H. Daffer

Jet Propulsion Laboratory, California Institute of Technology

J. R. Drummond

Dalhousie University

University of Toronto

P. F. Fogal

University of Toronto

E. Farahani

University of Toronto

C. Fayt

Belgian Institute for Space Aeronomy

A. Fraser

University of Toronto

University of Edinburgh

F. Goutail

Institut National des Sciences de l'Univers

F. Hendrick

Belgian Institute for Space Aeronomy

F. Kolonjari

University of Toronto

R. Lindenmaier

University of Toronto

G. Manney

Jet Propulsion Laboratory, California Institute of Technology

New Mexico Institute of Mining and Technology

C. T. McElroy

Environment Canada

York University

C. A. McLinden

Environment Canada

J. Mendonca

University of Toronto

J. H. Park

University of Toronto

B. Pavlovic

University of Toronto

A. Pazmino

Institut National des Sciences de l'Univers

C. Roth

University of Saskatchewan

V. Savastiouk

Full Spectrum Science Inc.

K. A. Walker

University of Waterloo

University of Toronto

D. Weaver

University of Toronto

X. Zhao

University of Toronto

Atmospheric Measurement Techniques

1867-1381 (ISSN) 1867-8548 (eISSN)

Vol. 5 927-953


Rymd- och flygteknik

Meteorologi och atmosfärforskning