Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 2 2007 10.5194/acpd-7-3333-2007 http://www.atmos-chem-phys-discuss.net/7/3333/2007/ http://www.atmos-chem-phys-discuss.net/7/3333/2007/acpd-7-3333-2007.html http://www.atmos-chem-phys-discuss.net/7/3333/2007/acpd-7-3333-2007.pdf 3333 3395 2007-03-02 Validation of MIPAS-ENVISAT NO₂ operational data G. Wetzel gerald.wetzel@imk.fzk.de A. Bracher B. Funke F. Goutail F. Hendrick J.-C. Lambert S. Mikuteit C. Piccolo M. Pirre A. Bazureau C. Belotti T. Blumenstock M. De Mazière H. Fischer N. Huret D. Ionov M. López-Puertas G. Maucher H. Oelhaf J.-P. Pommereau R. Ruhnke M. Sinnhuber G. Stiller M. Van Roozendael G. Zhang Institut für Meteorologie und Klimaforschung (IMK), Forschungszentrum Karlsruhe, Karlsruhe, Germany Institute of Environmental Physics and Remote Sensing (IUP/IFE), University of Bremen, Bremen, Germany Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Cientificas, Granada, Spain Service d'Aéronomie, CNRS, Verrières-le-Buisson, France Belgian Institute for Space Aeronomy (IASB-BIRA), Brussels, Belgium Oxford University, Oxford, UK Laboratoire de Physique et Chimie de l'Environnement (LPCE), CNRS, Orléans, France IFAC-CNR, Firenze, Italy now at: Yantai University, Yantai, China The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument was launched aboard the environmental satellite ENVISAT into its sun-synchronous orbit on 1 March 2002. The short-lived species NO₂ is one of the key target products of MIPAS that are operationally retrieved from limb emission spectra measured in the stratosphere and mesosphere. Within the MIPAS validation activities, a large number of independent observations from balloons, satellites and ground-based stations have been compared to European Space Agency (ESA) version 4.61 operational NO₂ data comprising the time period from July 2002 until March 2004 where MIPAS measured with full spectral resolution. Comparisons between MIPAS and balloon-borne observations carried out in 2002 and 2003 in the Arctic, at mid-latitudes, and in the tropics show a very good agreement below 40 km altitude with a mean deviation of roughly 3%, virtually without any significant bias. The comparison to ACE satellite observations exhibits only a small negative bias of MIPAS which appears not to be significant. The independent satellite instruments HALOE, SAGE II, and POAM III confirm in common for the spring-summer time period a negative bias of MIPAS in the Arctic and a positive bias in the Antarctic middle and upper stratosphere exceeding frequently the combined systematic error limits. In contrast to the ESA operational processor, the IMK/IAA retrieval code allows accurate inference of NO₂ volume mixing ratios under consideration of all important non-LTE processes. Large differences between both retrieval results appear especially at higher altitudes, above about 50 to 55 km. These differences might be explained at least partly by non-LTE under polar winter conditions but not at mid-latitudes. Below this altitude region mean differences between both processors remain within 5% (during night) and up to 10% (during day) under undisturbed (September 2002) conditions and up to 40% under perturbed polar night conditions (February and March 2004). The intercomparison of ground-based NDACC observations shows no significant bias between the FTIR measurements in Kiruna (68° N) and MIPAS in summer 2003 but larger deviations in autumn and winter. The mean deviation over the whole comparison period remains within 10%. A mean negative bias of 15% for MIPAS daytime and 8% for nighttime observations has been determined for UV-vis comparisons over Harestua (60° N). Results of a pole-to-pole comparison of ground-based DOAS/UV-visible sunrise and MIPAS mid-morning column data has shown that the mean agreement in 2003 falls within the accuracy limit of the comparison method. Altogether, it can be indicated that MIPAS NO₂ profiles yield valuable information on the vertical distribution of NO₂ in the lower and middle stratosphere (below about 45 km) during day and night with an overall accuracy of about 10–20% and a precision of typically 5–15% such that the data are useful for scientific studies. In cases where extremely high NO₂ occurs in the mesosphere (polar winter) retrieval results in the lower and middle stratosphere are less accurate than under undisturbed atmospheric conditions. Abrams, M. C., Chang, A. Y., Gunson, M. R., Abbas, M. M., Goldman, A., Irion, F. W., Michelsen, H. A., Newchurch, M. J., Rinsland, C. P., Stiller, G. P., and Zander, R.: On the assessment and uncertainty of atmospheric trace gas burden measurements with high resolution infrared solar occultation spectra from space by the ATMOS experiment, Geophys. Res. Lett., 23(17), 2337–2340, doi:10.1029/96GL01794, 1996. Amekudzi, L. K., Bracher, A., Meyer, J., Rozanov, A., Bovensmann, H., and Burrows J. P.: Lunar occultation with SCIAMACHY: First retrieval results, Adv. Space Res., 36, 906–914, 2005. Bernath, P. F., McElroy, C. T., Abrams, M. C., et al.: Atmospheric Chemistry Experiment (ACE): Mission Overview, Geophys. Res. Lett., 32, L15S01, doi:10.1029/2005GL022386, 2005. Bertaux, J. L., Mégie, G., Widemann, T., Chassefière, E., Pellinen, R., Korylla, E., Korpela, S., and Simon, P.: Monitoring of ozone trend by stellar occultations: The GOMOS Instrument, Adv. Space Res., 11, 237–242, 1991. Blumenstock, T., Fischer, H., Friedle, A., Hase, F., and Thomas, P.: Column amounts of ClONO₂, HCl, HNO₃, and HF from ground-based FTIR measurements made near Kiruna, Sweden in late winter 1994, J. Atmos. Chem., 26(3), 311–321, 1997. Bovensmann, H., Burrows, J. P., Buchwitz, M., Frerick, J., No\"el, S., Rozanov, V. V., Chance, K. V., and Goede, A. H. P.: SCIAMACHY - Mission objectives and measurement modes, J. Atmos. Sci., 56, 125–150, 1999. Bracher, A., Sinnhuber, M., Rozanov, A., and Burrows, J. P.: Using a photochemical model for the validation of NO₂ satellite measurements at different solar zenith angles, Atmos. Chem. Phys., 5, 393–408, 2005. Brasseur, G. and Solomon, S.: Aeronomy of the middle atmosphere (third edition), Atmos. Oceanograph. Sci. Lib., p. 336 ff, Springer, Dordrecht, The Netherlands, 2005. Carlotti, M.: Global-fit approach to the analysis of limb-scanning atmospheric measurements, Appl. Opt., 27, 3250–3254, 1988. Chance, K., Traub, W. A., Johnson, D. G., Jucks, K. W., Ciarpallini, P., Stachnik, R. A., Salawitch, R. J., and Michelsen, H. A.: Simultaneous measurements of stratospheric HO_x, NO_x, and Cl_x: Comparison with a photochemical model, J. Geophys. Res., 101, 9031–9043, 1996. Chu, W. P. and McCormick, M. P.: SAGE observations of stratospheric nitrogen dioxide, J. Geophys. Res., 91, 5465–5476, 1986. Coffey, M., Mankin, W., and Goldman, A.: Simultaneous spectroscopic determination of the latitudinal, seasonal, and diurnal variability of stratospheric N₂O, NO, NO₂, and HNO₃, J. Geophys. Res., 86, 7331–7341, 1981. Cunnold, D. M., Zawodny, J. M., Chu, W. P., Pommereau, J. P., Goutail, F., Lenoble, J., McCormick, M. P., Veiga, R. E., Murcray, D., Iwagami, N., Shibasaki, K., Simon, P. C., and Peetermans, W.: Validation of SAGE II NO₂ measurements, J. Geophys. Res., 96, 12 913–12 925, 1991. De Mazière, M., Van Roozendael, M., Hermans, C., Simon, P. C., Demoulin, P., Roland, G., and Zander, R.: Quantitative evaluation of the post - Mount Pinatubo NO₂ reduction and recovery, based on 10 years of Fourier transform infrared and UV-visible spectroscopic measurements at Jungfraujoch, J. Geophys. Res., 103(D9), 10 849–10 858, doi:10.1029/97JD03362, 1998. Denis, L., Roscoe, H. K., Chipperfield, M. P., Van Roozendael, M., and Goutail, F.: A new software suite for NO₂ vertical profile retrieval from ground-based zenith-sky spectrometers, J. Quant. Spectrosc. Radiat. Transfer, 92, 321–333, 2005. Dessler, A. E., Kawa, S. R., Considine, D. B., Waters, J. W., Froidevaux, L., and Kumer, J. B.: UARS measurements of ClO and NO₂ at 40 and 46 km and implications for the model "ozone deficit", Geophys. Res. Lett., 23, 339–342, 1996. Errera, Q. and Fonteyn, D.: Four-dimensional variational chemical assimilation of CRISTA stratospheric measurements, J. Geophys. Res., 106, 12 253–12 265, 2001. Fischer, H. and Oelhaf, H.: Remote sensing of vertical profiles of atmospheric trace constituents with MIPAS limb-emission spectrometers, Appl. Opt., 35, 2787–2796, 1996. % %Fischer, H., Carli, B., Oelhaf, H., et al.: MIPAS: An instrument for %atmospheric and climate research, Atmos. Chem. Phys. Discuss., in %preparation, 2007. Flaud, J.-M., Piccolo, C., Carli, B., Perrin, A., Coudert, L. H., Teffo, J.-L., and Brown, L. R.: Molecular line parameters for the MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) experiment, J. Atmos. Ocean. Opt., 16, 172–182, 2003. Friedl-Vallon, F., Maucher, G., Seefeldner, M., Trieschmann, O., Kleinert, A., Lengel, A., Keim, C., Oelhaf, H., and Fischer, H.: Design and characterization of the balloon-borne Michelson Interferometer for Passive Atmospheric Sounding (MIPAS-B2), Appl. Opt., 43, 3335–3355, 2004. Funke, B., López-Puertas, M., Stiller, G. P., von Clarmann, T., and Höpfner, M.: A new non-LTE retrieval method for atmospheric parameters from MIPAS-Envisat emission spectra, Adv. Space Res., 27(6–7), 1099–1104, 2001. Funke, B., López-Puertas, M., von Clarmann, T., Stiller, G. P., Fischer, H., Glatthor, N., Grabowski, U., Höpfner, M, Kellmann, S., Kiefer, M., Linden, A., Mengistu Tsidu, G., Milz, M., Steck, T., and Wang, D. Y.: Retrieval of stratospheric NO_x from 5.3 and 6.2 $\mu $m nonlocal thermodynamic equilibrium emissions measured by Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat, J. Geophys. Res., 110, D09302, doi:10.1029/2004JD005225, 2005a. Funke, B., López-Puertas, M., Gil-López, S., von Clarmann, T., Stiller, G. P., Fischer, H., and Kellmann, S.: Downward transport of upper atmospheric NOx into the polar stratosphere and lower mesosphere during the Antarctic 2003 and Arctic 2002/2003 winters, J. Geophys. Res., 110, D24308, doi:10.1029/2005JD006463, 2005b. Gille, J. C. and Russell III, J. M.: The Limb Infrared Monitor of the Stratosphere: Experiment description, performance, and results, J. Geophys. Res., 89, 5125–5140, 1984. Gordley, L. L., Russell, J. M. I., Mickley, L. J., Frederick, J. E., Park, J. H., Stone, K. A., Beaver, G. M., McInerney, J. M., Deaver, L. E., Toon, G. C., Murcray, F. J., Blatherwick, R. D., Gunson, M. R., Abbatt, J. P. D., Mauldin, R. L. I., Mount, G. H., Sen, B., and Blavier, J.-F.: Validation of nitric oxide and nitrogen dioxide measurements made by the Halogen Occultation Experiment for UARS platform, J. Geophys. Res., 101(D6), 10 241–10 266, doi:10.1029/95JD02143, 1996. Hase, F., Hannigan, J. W., Coffey, M. T., Goldman, A., Höpfner, M., Jones, N. B., Rinsland, C. P., and Wood, S. W.: Intercomparison of retrieval codes used for the analysis of high-resolution, ground-based FTIR measurements, J. Quant. Spectrosc. Radiat. Transfer, 87(1), 25–52, 2004. Hendrick, F., Barret, B., Van Roozendael, M., Boesch, H., Butz, A., De Mazière, M., Goutail, F., Hermans, C., Lambert, J.-C., Pfeilsticker, K., and Pommereau, J.-P.: Retrieval of nitrogen dioxide stratospheric profiles from ground-based zenith-sky UV-visible observations: validation of the technique through correlative comparisons, Atmos. Chem. Phys., 4, 2091–2106, 2004. Höpfner, M., Oelhaf, H., Wetzel, G., Friedl-Vallon, F., Kleinert, A., Lengel, A., Maucher, G., Nordmeyer, H., Glatthor, N., Stiller, G., von Clarmann, T., Fischer, H., Kröger, C., and Deshler, T.: Evidence of scattering of tropospheric radiation by PSCs in mid-IR limb emission spectra: MIPAS-B observations and KOPRA simulations, Geophys. Res. Lett., 29(8), 1278, doi:10.1029/2001GL014443, 2002. Koike, M., Kondo, Y., Matthews, W. A., Johnston, P. V., Nakajima, H., Kawaguchi, A., Nakane, H., Murata, I., Budiyono, A., Kanada, M., and Toriyama, N.: Assessment of the uncertainties in the NO₂ and O₃ measurements by visible spectrometers, J. Atmos. Chem., 32, 121–145, 1999. Kondo, Y., Matthews, W. A., Iwata, A., and Takagi, M.: Measurements of nitric oxide from 7–32 km and its diurnal variation in the stratosphere, J. Geophys. Res., 90, 3813–3819, 1985. Kouker, W., Langbein, I., Reddmann, T., and Ruhnke, R.: The Karlsruhe simulation model of the middle atmosphere (KASIMA), version 2, Rep. FZKA 6278, Forschungszentrum Karlsruhe GmbH, Karlsruhe, Germany, 1999. Lambert, J.-C., Van Roozendael, M., De Mazière, M., Simon, P. C., Pommereau, J.-P., Goutail, F., Sarkissian, A., and Gleason, J. F.: Investigation of pole-to-pole performances of spaceborne atmospheric chemistry sensors with the NDSC, J. Atmos. Sci., 56, 176–193, 10.1175/1520-0469, 1999. Lambert, J.-C., Hansen, G., Soebijanta, V., Thomas, W., Van Roozendael, M., Balis, D. S., Fayt, C., Gerard, P., Gleason, J. F., Granville, J., Labow, G., Loyola, D., Van Geffen, J. H. G., Van Oss, R. F., Zehner, C., and Zerefos, C. S.: ERS-2 GOME GDP3.0 Implementation and validation, ESA Technical Note ERSE-DTEX-EOAD-TN-02-0006, 138 pp., edited by: Lambert, J.-C. (IASB), November 2002. Langematz, U., Labitzke, K., and Reimer, E.: Synoptic analysis and trajectories during the MAP/GLOBUS campaign 1983. Planet. Space Sci., 35, 525–538, doi:10.1016/0032-0633(87)90120-6, 1987. López-Puertas, M., and Taylor, F. W.: Non-LTE radiative transfer in the atmosphere, World Sci. Pub., River Edge, N. J., 2001. Lumpe, J. D., Bevilacqua, R. M., Hoppel, K. W., Randall, C. E.: POAM III retrieval algorithm and error analysis, J. Geophys. Res.107(D21), 4575, doi:10.1029/2002JD002137, 2002. Marchand, M., Bekki, S., Hauchecorne, A., and Bertaux, J.-L.: Validation of the self-consistency of GOMOS NO₃, NO₂ and O₃ data using chemical data assimilation, Geophys. Res. Lett., 31, L10107, doi:10.1029/2004GL019631, 2004. McHugh, M., Magill, B., Walker, K. A., Boone, C. D., Bernath, P. F., and Russell III, J. M.: Comparison of atmospheric retrievals from ACE and HALOE, Geophys. Res. Lett., 32, L15S10, doi:10.1029/2005GL022403, 2005. McKenzie, R. L., Johnston, P. V., McElroy, C. T., Kerr, J. B., and Solomon, S.: Altitude distributions of stratospheric constituents from ground-based measurements at twilight, J. Geophys. Res., 96(D8), 15 499–15 511, doi:10.1029/91JD01361, 1991. Meyer, J., Bracher, A., Rozanov, A., Schlesier, A. C., Bovensmann, H., and Burrows, J. P.: Solar occultation with SCIAMACHY: algorithm description and first validation, Atm. Chem. Phys., 5, 1589–1604, 2005. Moreau, G., Robert, C., Catoire, V., Chartier, M., Camy-Peyret, C., Huret, N., Pirre, M., and Pomathiod, L.: SPIRALE: A multispecies in situ balloon-borne instrument with six tunable diode laser spectrometers, Appl. Opt., 44, 5972–5989, 2005. Nakajima, H., Sugita, T., Yokota, T., Ishigaki, T., Mogi, Y., Araki, N., Waragai, K., Kimura, N., Iwazawa, T., Kuze, A., Tanii, J., Kawasaki, H., Horikawa, M., Togami, T., Uemura, N., Kobayashi, H., and Sasano, Y.: Characteristics and performance of the Improved Limb Atmospheric Spectrometer-II (ILAS-II) on board the ADEOS-II satellite, J. Geophys. Res., 111, D11S01, doi:10.1029/2005JD006334, 2006. Nasa Langley Research Center: SAGE III – The Stratospheric Aerosol and Gas Experiment III, SAGE III instrument, http://www-sage3.larc.nasa.gov/, 2006. Newchurch, M. J., Allen, M., Gunson, M. R., Salawitch, R. J., Collins, G. B., Huston, K. H., Abbas, M. M., Abrams, M. C., Chang, A. Y., Fahey, D. W., Gao, R. S., Irion, F. W., Loewenstein, M., Manney, G. L., Michelsen, H. A., Podolske, J. R., Rinsland, C. P., and Zander, R.: Stratospheric NO and NO₂ abundances from ATMOS solar-occultation measurements, Geophys. Res. Lett., 23, 2373–2376, 1996. Notholt, J. and Schrems, O.: Ground-based FTIR measurements of vertical column densities of several trace gases above Spitsbergen, Geophys. Res. Lett., 21(13), 1355–1358, doi:10.1029/93GL01786, 1994. Noxon, J. F., Whipple, Jr., E. C., and Hyde, R. S.: Stratospheric NO₂. 1. Observational method and behavior at mid-latitude, J. Geophys. Res., 84, 5047–5065, 1979. Payan, S., Camy-Peyret, C., Jeseck, P. Hawat, T., Pirre, M., Renard, J.-B., Robert, C., Lefèvre, F., Kanzawa, H., and Sasano, Y.: Diurnal and nocturnal distribution of stratospheric NO₂ from solar and stellar occultation measurements in the Arctic vortex: Comparison with models and ILAS satellite measurements, J. Geophys. Res., 104, 21 585–21 593, 1999. Pfeilsticker, K. and Platt, U.: Airborne Measurements during the Arctic Stratospheric Experiment: Observation of O₃ and NO₂, Geophys. Res. Lett. 21, 1375–1378, 1994. Piters, A. J. M., Bramstedt, K., Lambert, J.-C., and Kirchhoff, B.: Overview of SCIAMACHY validation: 2002-2004, Atmos. Chem. Phys., 6, 127-148, 2006. Pommereau, J.-P. and Goutail, F.: O₃ and NO₂ groundbased measurements by visible spectroscopy during Arctic winter and spring, 1988, Geophys. Res. Lett., 15, 891–894, 1988. Pommereau, J.-P. and Piquard, J.: Ozone and nitrogen dioxide vertical distributions by uv-visible solar occultation from balloons, Geophys. Res. Lett., 21, 1227–1230, 1994. Randall C. E., Rusch, D. W., Bevilacqua, R. M., Hoppel, K. W., and Lumpe, J. D.: Polar ozone and aerosol measurement (POAM) II stratospheric NO₂, 1993–1996, J. Geophys. Res., 103, 28 361–28 371, 1998. Randall, C. E., Lumpe, J. D., Bevilacqua, R. M., Hoppel, K. W., Shettle, E. P., Rusch, D. W., Gordley, L. L., Kreher, K., Pfeilsticker, K., Boesch, H., Toon, G., Goutail, F., and Pommereau, J.-P.: Validation of POAM III NO₂ measurements, J. Geophys. Res., 107(D20), 4432, doi:10.1029/2001JD001520, 2002. Raspollini, P., Belotti, C., Burgess, A., Carli, B., Carlotti, M., Ceccherini, S., Dinelli, B. M., Dudhia, A., Flaud, J.-M., Funke, B., Höpfner, M., López-Puertas, M., Payne, V., Piccolo, C., Remedios, J. J., Ridolfi, M., and Spang, R.: MIPAS level 2 operational analysis, Atmos. Chem. Phys., 6, 5605–5630, 2006. Reburn, W. J., Remedios, J. J., Morris, P. E., Rodgers, C. D., Taylor, F. W., Kerridge, B. J., Knight, R. J., Ballard, J., Kumer, J. B., and Massie, S. T.: Validation of nitrogen dioxide measurements from the Improved Stratospheric and Mesospheric Sounder, J. Geophys. Res., 101, 9873–9895, 1996. Reimer, E. and Kaupp, H.: Source identification of odour compounds using trajectories, Proc. ECO-INFORMA 97, Eco-Informa Press, Bayreuth, 572–577, 1997. Renard, J.-B., Pirre, M., Robert, C., Moreau, G., Huguenin, D., and Russell III, J. M.: Nocturnal vertical distribution of stratospheric O₃, NO₂ and NO₃ from balloon measurements, J. Geophys. Res., 101, 28 793–28 804, 1996. Rodgers, C.: Inverse methods for atmospheric sounding: Theory and practice, World Sci. Pub., River Edge, N. J., 2000. Roscoe, H., Kerridge, B., Gray, L., Wells, R., and Pyle, J.: Simultaneous measurements of stratospheric NO and NO₂ and their comparison with model predictions, J. Geophys. Res., 91, 5405–5419, 1986. Roscoe, H. K., Johnston, P. V., Van Roozendael, M., et al.: Slant column measurements of O₃ and NO₂ during the NDSC intercomparison of zenith-sky UV-visible spectrometers in June 1996, J. Atmos. Chem., 32, 281–314, 1999. Rothman, L. S., Jacquemart, D., Barbe, A., et al.: The HITRAN 2004 molecular spectroscopic database, J. Quant. Spectrosc. Radiat. Transfer, 96, 139–204, 2005. Rozanov A., Bovensmann, H., Bracher, A., Hrechanyy, S., Rozanov, V., Sinnhuber, M., Stroh, F., and Burrows, J. P.: NO₂ and BrO vertical profile retrieval from SCIAMACHY limb measurements: Sensitivity studies, Adv. Space Res., 36, 846–854, 2005. Russell III, J. M., Farmer, C., Rinsland, C., Zander, R., Froidevaux, L., Toon, G., Gao, B., Shaw, J., and Gunson, M.: Measurements of odd nitrogen compounds in the stratosphere by the ATMOS experiment on Spacelab 3, J. Geophys. Res., 93, 1718–1736, 1988. Russell III, J. M., Gordley, L. L., Gordley, J. H., Park, J. H., Drayson, S. R., Hesketh, W. D., Cicerone, R. J., Tuck, A. F., Frederick, J. E., Harries, J. E., and Crutzen, P. J.: The Halogen Occultation Experiment, J. Geophys. Res., 98, 10 777–10 797, 1993. Sasano, Y., Suzuki, M., Yokota, T., and Kanzawa, H.: Improved Limb Atmospheric Spectrometer (ILAS) for stratospheric ozone layer measurements by solar occultation technique, Geophys. Res. Lett., 26, 197–200, 1999. Sen, B., Toon, G. C., Osterman, G. B., Blavier, J.-F., Margitan, J. J., Salawitch, R. J., and Yue, G. K.: Measurements of reactive nitrogen in the stratosphere, J. Geophys. Res., 103, 3571–3585, 1998. Stiller, G. P., von Clarmann, T., Funke, B., Glatthor, N., Hase, F., Höpfner, M., and Linden, A.: Sensitivity of trace gas abundances retrievals from infrared limb emission spectra to simplifying approximations in radiative transfer modeling, J. Quant. Spectrosc. Radiat. Transfer, 72(3), 249–280, 2002. Vandaele, A. C., Hermans, C., Simon, P. C., Carleer, M., Colin, R., Fally, S., Merienne, M.-F., Jenouvrier, A., and Coquart, B.: Measurements of NO₂ absorption cross-section from 42 000 cm^−1 to 10 000 cm^−1 (238–1000 nm) at 220 K and 294 K, J. Quant. Spectrosc. Radiat. Transfer, 59, 171–184, 1998. Vandaele, A. C., Fayt, C., Hendrick, F., et al.: An intercomparison campaign of ground-based UV-visible measurements of NO₂, BrO, and OClO slant columns: Methods of analysis and results for NO₂, J. Geophys. Res., 110, D08305, doi:10.1029/2004JD005423, 2005. von Clarmann, T., Chidiezie Chineke, T., Fischer, H., Funke, B., García-Comas, M., Gil-López, S., Glatthor, N., Grabowski, U., Höpfner, M., Kellmann, S., Kiefer, M., Linden, A., López-Puertas, M., López-Valverde, M. A., Mengistu Tsidu, G., Milz, M., Steck, T., and Stiller, G. P.: Remote sensing of the middle atmosphere with MIPAS, in: Remote sensing of clouds and the atmosphere VII, edited by: Schäfer, K., Lado-Bordowsky, O., Comerón, A., and Picard, R. H., SPIE Proc., 4882, 172–183, 2003. von Clarmann, T.: Validation of remotely sensed profiles of atmospheric state variables: strategies and terminology, Atmos. Chem. Phys., 6, 4311–4320, (Addendum, Atmos. Chem. Phys., 6, 5547, 2006.) 2006. Webster, C., May, R., Toumi, R., and Pyle, J.: Active nitrogen partitioning and the nighttime formation of N₂O$_5$ in the stratosphere: Simultaneous in situ measurements of NO, NO₂, HNO₃, O₃, and N₂O using the BLISS diode laser spectrometer, J. Geophys. Res., 95, 13 851–13 866, 1990. Wetzel, G., Oelhaf, H., von Clarmann, T., Fischer, H., Friedl-Vallon, F., Maucher, G., Seefeldner, M., Trieschmann, O., and Lefèvre, F.: Vertical profiles of N₂O$_5$, HO₂NO₂, and NO₂ inside the Arctic vortex, retrieved from nocturnal MIPAS-B2 infrared limb emission measurements in February 1995, J. Geophys. Res., 102, 19 177–19 186, 1997. Wetzel, G., Oelhaf, H., Friedl-Vallon, F., Kleinert, A., Lengel, A., Maucher, G., Nordmeyer, H., Ruhnke, R., Nakajima, H., Sasano, Y., Sugita, T., and Yokota, T.: Intercomparison and validation of ILAS-II version 1.4 target parameters with MIPAS-B measurements, J. Geophys. Res., 111, D11S06, doi:10.1029/2005JD006287, 2006. Zander, R., Demoulin, P., Mahieu, E., Adrian, G. P., Rinsland, C. P., and Goldman, A.: ESMOS II/NDSC IR spectral fitting algorithms. Intercomparison exercise, in Proceedings of the Atmospheric Spectroscopy Applications Workshop, Reims, France, 8–10 September 1993, 7–12, 1994.