CRISTA-NF measurements with unprecedented vertical resolution during the RECONCILE aircraft campaign

Abstract

Abstract. The Cryogenic Infrared Spectrometers and Telescope for the Atmosphere -New Frontiers (CRISTA-NF), an airborne infrared limb-sounder, was operated aboard the high-flying Russian research aircraft M55-Geophysica during the Arctic RECONCILE campaign from January to March 2010. This paper describes the calibration process of the instrument and the retrieval algorithm employed and then proceeds to present retrieved trace gas volume mixing ratio cross-sections for one specific flight in this campaign. We are able to resolve the uppermost troposphere/lower stratosphere for several trace gas species for several kilometres below the flight altitude (16 to 19 km) with an unprecedented vertical resolution of 400 to 500 m for the limb-sounding technique. The instrument points sideways with respect to the flight direction. Therefore, the observations are also characterised by a rather high horizontal sampling along the flight track, which provides a full vertical profile every ≈15 km. Assembling the vertical trace gas profiles derived from CRISTA-NF measurements to cross-sections shows filaments of vortex and extra-vortex air masses in the vicinity of the polar vortex.During this campaign, the M55-Geophysica carried further instruments enabling trace gas volume mixing ratios derived from CRISTA-NF to be validated by comparing them with measurements by the in situ instruments HAGAR and FOZAN and observations by MIPAS-STR. This validation suggests that the retrieved trace gas volume mixing ratios are both qualitatively and quantitatively reliable.

Filamentary structure in chemical tracer distributions near the subtropical jet following a wave breaking event

“…Linearly derived precision and accuracy figures for the discussed species are given in Table 1; comparisons with measurements by other in situ and remote sensing instruments has ascertained the validity of these figures for a different research flight (see Ungermann et al, 2012). The vertical resolution is shown for an exemplary profile in Fig.…”

“…A detailed description of the first retrieval of this set of measurements is given by Weigel et al (2012). Ungermann et al (2012) improved this setup by employing a more accurate line-of-sight determination and a finer retrieval grid. In addition, horizontal regularisation was added to lower the impact of stochastic error sources on the results (see Ungermann, 2013).…”

Airborne limb-imaging measurements of temperature, HNO<sub>3</sub>, O<sub>3</sub>, ClONO<sub>2</sub>, H<sub>2</sub>O and CFC-12 during the Arctic winter 2015/2016: characterization, in situ validation and comparison to Aura/MLS

“…The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) instrument continues the heritage of the series of MIPAS (Michelson Interferometer for Passive Atmospheric Sounding; Fischer and Oelhaf, 1996;Piesch et al, 1996;Friedl-Vallon et al, 2004) and CRISTA (CRyogenic Infrared Spectrometers and Telescopes for the Atmosphere; Offermann et al, 1999;Ungermann et al, 2012) instruments. One major improvement of GLORIA compared to its limb-scanning precursors is the usage of an imaging array detector for significantly higher spatial sampling and precise relative pointing.…”

Synergy between middle infrared and millimeter-wave limb sounding of atmospheric temperature and minor constituents

“…Observations of MIPAS aboard Envisat (Fischer et al, 2008, and references therein) were utilized to study the chemical composition from tropospheric to mesospheric altitudes. Airborne observations by MIPAS-STR (e.g., Piesch et al, 1996;Woiwode et al, 2012, and references therein) and CRISTA-NF (e.g., Ungermann et al, 2012) showed that middle infrared observations allow the resolution of narrow vertical structures in trace gas distributions along flight track with high accuracy under cloud-free conditions. The next generation of infrared limb sounders involves imaging detectors, and the airborne prototype instrument GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) successfully demonstrated the capabilities of this new detection technique (Friedl-Vallon et al, 2014;Riese et al, 2014).…”