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International audience; Numerous vertical ozone profile data records collected over the past decades from space-based platforms have the potential to allow the ozone and climate communities to tackle a variety of research questions. A prime topic is the study and documentation of long-term changes in the vertical distribution of atmospheric ozone, as targeted by the recent SPARC/IO3C/IGACO-O3/NDACC Initiative (SI2N) and WMO’s ozone assessment. Such studies typically require data records with documented mutual consistency in terms of bias and long-term stability. Ground-based networks play a pivotal role in evaluating which satellite records comply with end-user requirements and are fit for their purpose. They provide high-quality, independent measurements on a pseudo- global scale from the ground up to the stratosphere.Here, we present an assessment of the long-term stability and mutual consistency of fourteen limb/occultation ozone profile data records, using NDACC/GAW/SHADOZ ozonesonde and NDACC lidar network data as reference standards. We show how a harmonized analysis framework and robust statistical methods allow us to derive reliable estimates of the drift, bias, and short-term variability of each satellite data record. We examine the dependence of these parameters on altitude and, whenever feasible, on latitude and season. The analysis is furthermore performed in four different ozone profile representations, as it turns out that auxiliary data used for unit and representation conversions can impact data quality. We discuss the mutual consistency and compliance of satellite data sets with respect to specific user requirements from GCOS and from climate research groups. We conclude by reflecting on the implication of our results for trend assessments on recently merged ozone profile records (Ozone_CCI, GOZCARDS, SWOOSH, ...)

Daily total ozone measurements are carried out in Tomsk, Central Siberia using Brewer Mark-IV spectrophotometer 049 since 2003. This instrument was used at Heiss Island, Franz Josef Land, Russia in 1988-1994. The accuracy of routine total ozone observations at direct sun measurements is 2-3%. Under cloudless conditions at air mass factor less than 4, the accuracy of total ozone direct sun measurements approaches 1%, while the accuracy of direct moon observations is 2-3%. SAOZ (Systeme d'Analyse par Observation Zenitale) is UV-visible (300-650 nm) diode array spectrometer developed at the Service d'Aeronomie, CNRS, France for monitoring stratospheric ozone and NO2. Zenith sky measurements of atmospheric gases at twilight (86°< solar zenith angle < 91°) are used. There are 17 SAOZ instruments in SAOZ network around the world. Ttree instruments are located at the Arctic Circle in Russia at Zhigansk since 1992, Salekhard since 1998 and Anadyr station in Far East, Russia since January 2011. Accuracy of total ozone measurements is 6% and 10% for nitrogen dioxide observations. The results of ozone monitoring are compared with data of ozone measurements in polar vortex conditions at these stations are in SAOZ database. Currently, we use 2Z-ECC ozonesondes for ozone profile observations in winter/spring periods at Salekhard aerological station. The results of ozonesounding at Salekhard station are in NDACC database. The recent results of Brewer, SAOZ total ozone observations in Siberia and Far East, Russia, data of ozone profile observations in western Siberia at Salekhard aerological station in winter/spring sesons of 2011 and 2012 will be presented and discussed.

The PCW (Polar Communications and Weather) mission is a dual satellite mission with each satellite in a highly eccentric orbit with apogee ~ 42,000 km and a period (to be decided) in the 12-24 hour range to deliver continuous communications and meteorological data over the Arctic and environs. At and near apogee the viewing is quasi-geostationary due to the slow satellite motion. The operational meteorological instrument is a 21-channel spectral imager with UV, visible, NIR and MIR channels similar to MODIS and ABI. The PHEMOS WCA (Weather, Climate and Air quality) mission is an atmospheric science complement to the operational PCW mission. The PHEMOS WCA instrument package consists of FTS and UVS imaging sounders with viewing range of ~4.5 degrees or a Field of Regard (FoR) ~ 3400x3400 km2 from near apogee. The spatial resolution at apogee of each imaging sounder is targeted to be 10Ã--10 km2 or better and the image repeat time is targeted at ~ 2 hours or better. The FTS has 4 bands that span the MIR and NIR. The MIR bands cover 700-1500 cm-1 and 1800-2700 cm-1 with a spectral resolution of 0.25 cm-1 i,e, a similar spectral resolution to IASI. They should provide vertical tropospheric profiles of temperature and water vapour in addition to partial columns of other gases of interest for air quality such as O3, CO, HCN, CH3OH, etc and also CO2 and CH4. The two NIR bands cover 5990-6010 cm-1 (0.25 cm-1) and 13060-13168 cm-1 (0.5 cm-1) and target columns of CO2 and CH4 and the O2-A band for surface pressure, aerosol OD and albedo. The UVS is an imaging spectrometer that covers the spectral range of 280 â€" 650 nm with 0.9 nm resolution and targets the tropospheric column densities of O3 and NO2. It is also planned to obtain the tropospheric columns of BrO, SO2, HCHO and (HCO)2 and the aerosol index (AI) as well as stratospheric columns of O3, NO2 and BrO. The quasi-stationary viewing will provide the ability to measure the diurnal behavior of atmospheric properties under the satellites and the ability to provide data for weather forecasting and also chemical data assimilation. Important goals for PHEMOS-WCA include measurement of meteorological and air quality data and the measurement of changes in CO2 and CH4 throughout the day-lit hours in the NIR near apogee (see FTS poster). In addition, the imaging design is to be sufficiently flexible so that it can be directed at special events possibly with the FoR reduced to have more rapid spatial coverage. In this paper we will outline the scientific objectives, status of retrieval algorithms and also the viewing geometry necessary with 2 satellites. PHEMOS WCA Phase A study was completed in March 2012. It was funded by the Canadian Space Agency (CSA).