CO measurements from the ACE-FTS satellite instrument: data analysis and validation using ground-based, airborne and spaceborne observations

Abstract

Published by Copernicus Publications on behalf of the European Geosciences Union. constructed from averaged ACE-FTS data over China and completed with TES data over the 5 same area below 6 km. The vertical sensitivity of each CO sounding type of instrument is also 6 reported on the right-hand side of this plot. MW and TIR refer to millimeter-wave and 7 thermal infrared spectral regions, respectively. 8 Fig. 1. Schematic plot of a standard atmospheric CO profile, with the different sources of production (blue) and destruction/sinks (red) as a function of altitude. The CO profile was constructed from averaged ACE-FTS data over China and completed with TES data over the same area below 6 km. The vertical sensitivity of each CO sounding type of instrument is also reported on the right-hand side of this plot. MW and TIR refer to millimeter-wave and thermal infrared spectral regions, respectively.Abstract. The Atmospheric Chemistry Experiment (ACE) mission was launched in August 2003 to sound the atmosphere by solar occultation. Carbon monoxide (CO), a good tracer of pollution plumes and atmospheric dynamics, is one of the key species provided by the primary instrument, the ACE-Fourier Transform Spectrometer (ACE-FTS). This instrument performs measurements in both the CO 1-0 and 2-0 ro-vibrational bands, from which vertically resolved CO concentration profiles are retrieved, from the mid-troposphere to the thermosphere. This paper presents an updated description of the ACE-FTS version 2.2 CO data product, along with a comprehensive validation of these profiles using available observations (February 2004 to December 2006. We have compared the CO partial columns with ground-based measurements using Fourier transform infrared spectroscopy and millimeter wave radiometry, and the volume mixing ratio profiles with airborne (both high-altitude balloon flight and airplane) observations. CO satellite observations provided by nadir-looking instruments (MOPITT and TES) as well as limb-viewing remote sensors (MIPAS, SMR and MLS) were also compared with the ACE-FTS CO products. We show that the ACE-FTS measurements provide CO profiles with small retrieval errors (better than 5% from the upper troposphere to 40 km, and better than 10% above). These observations agree well with the correlative measurements, considering the rather loose coincidence criteria in some cases. Based on the validation exercise we assess the following uncertainties to the ACE-FTS measurement data: better than 15% in the upper troposphere (8-12 km), than 30% in the lower stratosphere (12-30 km), and than 25% from 30 to 100 km.

Comparison of XCO abundances from the Total Carbon Column Observing Network and the Network for the Detection of Atmospheric Composition Change measured in Karlsruhe

“…In recent years, several satellite missions were launched and provided long-term observations of atmospheric CO (e.g. Buchwitz et al, 2007;Deeter et al, 2003;Clerbaux et al, 2008). These measurements are confirmed and validated by ground-based data records which provide similar quantities as measured by satelliteborne instruments (de Laat et al, 2010).…”

Five years of CO, HCN, C<sub>2</sub>H<sub>6</sub>, C<sub>2</sub>H<sub>2</sub>, CH<sub>3</sub>OH, HCOOH and H<sub>2</sub>CO total columns measured in the Canadian high Arctic

“…The black and red error bars correspond to the standard deviation of the a priori covariance matrix used in the retrievals and the standard deviations around the mean retrieved profiles, respectively, at each layer. All the a priori VMR profiles exhibit large contributions in the boundary layer and the troposphere, and decrease to almost zero at 50 km, except for CO, for which the sources are dominated by CH 4 oxidation at this altitude (Clerbaux et al, 2008).…”

“…As shown previously, the ACE-FTS measures VMR profiles of CO (Clerbaux et al, 2008), hydrocarbons, such as HCN, C 2 H 6 , C 2 H 2 (Park et al, 2013) and HCOOH (González Abad et al, 2009) in the upper troposphere and lower stratosphere. In addition to these species, CH 3 OH and H 2 CO have been measured by the ACE-FTS globally (Dufour et al, , 2009) and in biomass burning plumes over northern high latitudes Tereszchuk et al, 2011Tereszchuk et al, , 2013 and in the Southern Hemisphere .…”

1997–2007 CO trend at the high Alpine site Jungfraujoch: a comparison between NDIR surface in situ and FTIR remote sensing observations

“…The spectroscopic parameters of the absorption lines have been taken from the HI-TRAN2004 database (Rothman et al, 2003) Clerbaux et al, 2008), in the 15.4-100 km and 6.5-15.4 km altitude ranges, respectively. This profile was extrapolated further down and set to 137 ppb for the first layer, considering the slope shown by the ACE-FTS averaged profile in the mid troposphere.…”