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Contact: Michelle Santee

Basic Information

Chlorine monoxide (ClO) is the dominant form of reactive chlorine in the stratosphere and is thus the principal agent for chlorine-catalyzed destruction of stratospheric ozone. The primary source of stratospheric chlorine is chlorofluorocarbons, or CFCs, chemical compounds composed of chlorine, fluorine, and carbon that are emitted by human activities at the surface. After they reach the upper stratosphere (primarily by upwelling in the tropics), the CFCs are broken down by high-energy UV radiation, liberating chlorine. Away from the polar regions, most of the chlorine released from CFCs resides in relatively benign reservoir species such as ClONO2 and HCl that do not directly destroy ozone. In the winter polar regions, however, heterogeneous chemical reactions on the surfaces of polar stratospheric clouds convert chlorine to highly reactive forms. Enhanced levels of ClO are a signal that ozone destruction is taking place.
The ClO Molecule
ClO molecule visualization

How it is part of MLS Science Objectives

One of the main objectives of the Aura mission in general and MLS in particular is to track the stability of the stratospheric ozone layer. Simultaneous measurements of HCl and ClO from MLS provide information on reservoir and reactive chlorine and the partitioning between them that is crucial for understanding (and thus predicting) stratospheric ozone depletion.

How EOS MLS measures ClO

The standard product for ClO is taken from the 640 GHz retrieval. ClO is strongly diurnal in the lower stratosphere.

ClO Information from the Spectroscopy Database

Quick Product Information for data version v4.2

  • Swath Name: ClO
  • Status Flag: Only use profiles for which the Status field is zero.
  • Useful Range: 147 - 1.0 hPa
  • DAAC Short Name: ML2CLO
  • Precision: Only use values for which the estimated precision is a positive number.
  • Quality Threshold: >1.3
  • Convergence Threshold: <1.05
Download EOS Aura MLS ClO 4.2 data

Publications related to the MLS ClO data product


  1. Khosrawi, F., O. Kirner, B. Sinnhuber, S. Johansson, M. Höpfner, M. Santee, L. Froidevaux, J. Ungermann, R. Ruhnke, W. Woiwode, H. Oelhaf, P. Braesicke, "Denitrification, dehydration and ozone loss during the 2015/2016 Arctic winter", Atmospheric Chemistry and Physics 17, 21, 12893-12910, doi:10.5194/acp-17-12893-2017, 2017. reprint
  2. Wohltmann, I., R. Lehmann, M. Rex, "A quantitative analysis of the reactions involved in stratospheric ozone depletion in the polar vortex core", Atmospheric Chemistry and Physics 17, 17, 10535-10563, doi:10.5194/acp-17-10535-2017, 2017. reprint


  1. Akiyoshi, H., T. Nakamura, T. Miyasaka, M. Shiotani, M. Suzuki, "A nudged chemistry-climate model simulation of chemical constituent distribution at northern high-latitude stratosphere observed by SMILES and MLS during the 2009/2010 stratospheric sudden warming", Journal of Geophysical Research: Atmospheres 121, 3, 1361-1380, doi:10.1002/2015jd023334, 2016. reprint
  2. Andersson, M.E., P.T. Verronen, D.R. Marsh, S.M. Paivarinta, J.M.C. Plane, "WACCM-D-Improved modeling of nitric acid and active chlorine during energetic particle precipitation", Journal of Geophysical Research: Atmospheres 121, 17, 10,328-10,341, doi:10.1002/2015jd024173, 2016. reprint
  3. Huang, L., J.H. Jiang, L. Murry, M. Damon, H. Su, N. Livesey, "Evaluation of UTLS carbon monoxide simulations in GMI and GEOS-Chem chemical transport models using Aura MLS observations", Atmospheric Chemistry and Physics 16, 5641-5663, doi:10.5194/acp-16-5641-2016, 2016. reprint
  4. Huijnen, V., J. Flemming, S. Chabrillat, Q. Errera, Y. Christophe, A. Blechschmidt, A. Richter, H. Eskes, "C-IFS-CB05-BASCOE: stratospheric chemistry in the Integrated Forecasting System of ECMWF", Geosci. Model Dev. 9, 9, 3071-3091, doi:10.5194/gmd-9-3071-2016, 2016. reprint
  5. Manney, G.L., Z.D. Lawrence, "The major stratospheric final warming in 2016: Dispersal of vortex air and termination of Arctic chemical ozone loss", Atmospheric Chemistry and Physics 16, 15371-15396, doi:10.5194/acp-2016-633, 2016.
  6. Millan, L., N. Livesey, M. Santee, J. Neu, G. Manney, R. Fuller, "Case studies of the impact of orbital sampling on stratospheric trend detection and derivation of tropical vertical velocities: solar occultation vs. limb emission sounding", Atmospheric Chemistry and Physics 16, 18, 11521-11534, doi:10.5194/acp-16-11521-2016, 2016. reprint
  7. Nakajima, H., I. Wohltmann, T. Wegner, M. Takeda, M.C. Pitts, L.R. Poole, R. Lehmann, M.L. Santee, M. Rex, "Polar Stratospheric Cloud evolution and chlorine activation measured by CALIPSO and MLS, and modelled by ATLAS", Atmospheric Chemistry and Physics 16, 16, 3311–3325, doi:10.5194/acp-16-3311-2016, 2016. reprint
  8. Nedoluha, G., B. Connor, T. Mooney, J. Barrett, A. Parrish, R.M. Gomez, I. Boyd, D. Allen, M. Kotkamp, S. Kremser, T. Deshler, P. Newman, M. Santee, "20 years of ClO measurements in the Antarctic lower stratosphere", Atmospheric Chemistry and Physics 16, 16, 10725-10734, doi:10.5194/acp-16-10725-2016, 2016. reprint
  9. Siskind, D., G. Nedoluha, F. Sassi, P. Rong, S. Bailey, M. Hervig, C. Randall, "Persistence of upper stratospheric wintertime tracer variability into the Arctic spring and summer", Atmospheric Chemistry and Physics 16, 12, 7957-7967, doi:10.5194/acp-16-7957-2016, 2016. reprint
  10. Stone, K., O. Morgenstern, D. Karoly, A. Klekociuk, W.J. French, N.L. Abraham, R. Schofield, "Evaluation of the ACCESS – chemistry–climate model for the Southern Hemisphere", Atmospheric Chemistry and Physics 16, 4, 2401-2415, doi:10.5194/acp-16-2401-2016, 2016. reprint


  1. Guo, D., Y. Su, C. Shi, J. Xu, A. Powell, "Double core of ozone valley over the Tibetan Plateau and its possible mechanisms", Journal of Atmospheric and Solar-Terrestrial Physics 130-131, 127-131, doi:10.1016/j.jastp.2015.05.018, 2015. reprint
  2. Kirner, O., R. Muller, R. Ruhnke, H. Fischer, "Contribution of liquid, NAT and ice particles to chlorine activation and ozone depletion in Antarctic winter and spring", Atmospheric Chemistry and Physics 15, 2019--2030, doi:10.5194/acp-15-2019-2015, 2015. reprint
  3. Kuttippurath, J., S. Godin-Beekmann, F. Lefevre, M.L. Santee, L. Froidevaux, A. Hauchecorne, "Variability in Antarctic ozone loss in the last decade 2004-2013: high-resolution simulations compared to Aura MLS observations", Atmospheric Chemistry and Physics 15, 10385-10397, doi:10.5194/acp-15-10385-2015, 2015. reprint
  4. Liberto, L.D., R. Lehmann, I. Tritscher, F. Fierli, J.L. Mercer, M. Snels, G.D. Donfrancesco, T. Deshler, B.P. Luo, J. Grooß, E. Arnone, B.M. Dinelli, F. Cairo, "Lagrangian analysis of microphysical and chemical processes in the Antarctic stratosphere: a case study", Atmospheric Chemistry and Physics 15, 12, 6651-6665, doi:10.5194/acp-15-6651-2015, 2015. reprint
  5. Manney, G., Z. Lawrence, M. Santee, W. Read, N. Livesey, A. Lambert, L. Froidevaux, H. Pumphrey, M. Schwartz, "A minor sudden stratospheric warming with a major impact: Transport and polar processing in the 2014/2015 Arctic winter", Geophysical Research Letters 42, 18, 7808-7816, doi:10.1002/2015gl065864, 2015. reprint
  6. Manney, G.L., Z.D. Lawrence, M.L. Santee, N.J. Livesey, A. Lambert, M.C. Pitts, "Polar processing in a split vortex: Arctic ozone loss in early winter 2012/2013", Atmospheric Chemistry and Physics 15, 5381– 5403, doi:10.5194/acp-15-5381-2015, 2015. reprint
  7. Pendlebury, D., D. Plummer, J. Scinocca, P. Sheese, K. Strong, K. Walker, D. Degenstein, "Comparison of the CMAM30 data set with ACE-FTS and OSIRIS: polar regions", Atmospheric Chemistry and Physics 15, 21, 12465-12485, doi:10.5194/acp-15-12465-2015, 2015. reprint
  8. Tang, X., Y. Liu, W. Wang, L. Song, W. Li, "Changes in stratospheric ClO and HCl concentrations under different greenhouse gas emission scenarios", J Meteorol Res 29, 4, 639-653, doi:10.1007/s13351-015-4065-3, 2015. reprint


  1. Blunden, J., D.S. Arndt, "State of the Climate in 2013", Bulletin of the American Meteorological Society 95, S1-S257, 2014.
  2. Damiani, A., B. Funke, M.L. Puertas, A. Gardini, T. von Clarmann, M.L. Santee, L. Froidevaux, R.R. Cordero, "Changes in the composition of the northern polar upper stratosphere in February 2009 after a sudden stratospheric warming", Journal of Geophysical Research: Atmospheres 119, 19, 11429-11444, doi:10.1002/2014JD021698, 2014. reprint


  1. Blunden, J., D.S. Arndt, "State of the Climate in 2012", Bulletin of the American Meteorological Society 94, S1-S238, 2013.
  2. Brakebusch, M., C.E. Randall, D.E. Kinnison, S. Tilmes, M.L. Santee, G.L. Manney, "Evaluation of Whole Atmosphere Community Climate Model simulations of ozone during Arctic winter 2004–2005", Journal of Geophysical Research 118, 6, 2673-2688, doi:10.1002/jgrd.50226, 2013. reprint
  3. Connor, B.J., T. Mooney, G.E. Nedoluha, J.W. Barrett, A. Parrish, J. Koda, M.L. Santee, R.M. Gomez, "Re-analysis of ground-based microwave ClO measurements from Mauna Kea, 1992 to early 2012", Atmospheric Chemistry and Physics 13, 8643-8650, doi:10.5194/acpd-12-30571-2012, 2013. reprint
  4. Khosravi, M., P. Baron, J. Urban, L. Froidevaux, A.I. Jonsson, Y. Kasai, K. Kuribayashi, C. Mitsuda, D.P. Murtagh, H. Sagawa, M.L. Santee, T.O. Sato, M. Shiotani, M. Suzuki, T. von Clarmann, K.A. Walker, S. Wang, "Diurnal variation of stratospheric and lower mesospheric HOCl, ClO and HO2 at the equator: comparison of 1-D model calculations with measurements by satellite instruments", Atmospheric Chemistry and Physics 13, 7587-7606, doi:10.5194/acp-13-7587-2013, 2013. reprint
  5. Schwartz, M.J., W.J. Read, M.L. Santee, N.J. Livesey, L. Froidevaux, A. Lambert, G.L. Manney, "Convectively Injected Water Vapor in the North American Summer Lowermost Stratosphere", Geophysical Research Letters 40, 10, 2316–2321, doi:10.1002/grl.50421, 2013. reprint
  6. Sugita, T., Y. Kasai, Y. Terao, S. Hayashida, G.L. Manney, W.H. Daffer, H. Sagawa, M. Suzuki, M. Shiotani, K.A. Walker, C.D. Boone, P.F. Bernath, "HCl and ClO profiles inside the Antarctic vortex as observed by SMILES in November 2009: comparisons HCl and ClO profiles inside the Antarctic vortex as observed by SMILES in November 2009: comparisons with MLS and ACE-FTS instruments", Atmospheric Measurement Techniques 6, 3099-3113, doi:10.5194/amt-6-3099-2013, 2013. reprint
  7. von Clarmann, T., "Chlorine in the stratosphere", Atmosfera 26, 415-458, doi:10.1016/S0187-6236(13)71086-5, 2013. reprint
  8. Wohltmann, I., T. Wegner, R. Mueller, R. Lehmann, M. Rex, G.L. Manney, M.L. Santee, P. Bernath, O. Suminska-Ebersoldt, F. Strohl, M. von Hobe, C.M. Volk, E. Hoesen, F. Ravegnani, A. Ulanovsky, V. Yushkov, "Uncertainties in modelling heterogeneous chemistry and Arctic ozone depletion in the winter 2009/2010", Atmospheric Chemistry and Physics 13, 3909-3929, doi:10.5194/acp-13-3909-2013, 2013. reprint


  1. Blunden, J., D.S. Arndt, "State of the Climate in 2011", Bulletin of the American Meteorological Society 93, S1--S264, doi:10.1175/2012BAMSStateoftheClimate.1, 2012. reprint
  2. Damiani, A., B. Funke, D.R. Marsh, M. Lopez-Puertas, M.L. Santee, L. Froidevaux, S. Wang, C.H. Jackman, T. von Clarmann, A. Gardini, R.R. Cordero, M. Storini, "Impact of January 2005 solar proton events on chlorine species", Atmospheric Chemistry and Physics 12, 4159–4179, doi:10.5194/acp-12-4159-2012, 2012. reprint
  3. Kuttippurath, J., S. Godin-Beekmann, F. Lefevre, G. Nikulin, M.L. Santee, L. Froidevaux, "Record-breaking ozone loss in the Arctic winter 2010/2011: comparison with 1996/1997", Atmospheric Chemistry and Physics 12, 7073-7085, doi:10.5194/acp-12-7073-2012, 2012. reprint
  4. Lange, A.D., M. Birk, G.D. Lange, F. Friedl-Vallon, O. Kiselev, V. Koshelets, G. Maucher, H. Oelhaf, A. Selig, P. Vogt, G. Wagner, J. Landgraf, "HCl and ClO in activated Arctic air first retrieved vertical profiles from TELIS submillimetre limb spectra", Atmospheric Measurement Techniques 5, 487-500, doi:10.5194/amtd-4-6497-2011, 2012. reprint
  5. Sato, T.O., H. Sagawa, D. Kreyling, T. Manabe, S. Ochiai, K. Kikuchi, P. Baron, J. Mendrok, J. Urban, D. Murtagh, M. Yasui, Y. Kasai, "Strato-mesospheric ClO observations by SMILES: error analysis and diurnal variation", Atmospheric Measurement Techniques 5, 2809-2825, doi:10.5194/amt-5-2809-2012, 2012. reprint


  1. Blunden, J., D.S. Arndt, M.O. Baringer, "State of the Climate in 2010", Bulletin of the American Meteorological Society 92, S1-S266, doi:10.1175/1520-0477-92.6.S1, 2011. reprint
  2. Feng, W., M.P. Chipperfield, S. Davies, G.W. Mann, K.S. Carslaw, S. Dhomse, L. Harvey, C. Randall, M.L. Santee, "Modelling the effect of denitrification on polar ozone depletion for Arctic winter 2004/2005", Atmospheric Chemistry and Physics 11, 6559-6573, doi:10.5194/acp-11-6559-2011, 2011. reprint
  3. Laat, A.T.J.d., M. van Weele, "The 2010 Antarctic ozone hole: Observed reduction in ozone destruction by minor sudden stratospheric warmings", Scientific Reports 1, 38, 1-8, doi:10.1038/srep00038, 2011. reprint
  4. Manney, G.L., M.L. Santee, M. Rex, N.J. Livesey, M.C. Pitts, P. Veefkind, E.R. Nash, I. Wohltmann, R. Lehmann, L. Froidevaux, L.R. Poole, M.R. Schoeberl, D.P. Haffner, J. Davies, V. Dorokhov, H. Gernandt, B. Johnson, R. Kivi, E. Kyro, N. Larsen, P.F. Levelt, A. Makshtas, C.T. McElroy, H. Nakajima, M.C. Parrondo, D.W. Tarasick, P.D. von Gathen, K.A. Walker, N.S. Zinoviev, "Unprecedented Arctic ozone loss in 2011", Nature 478, 469–475, doi:10.1038/nature10556, 2011. reprint
  5. Nedoluha, G.E., B.J. Connor, J. Barrett, T. Mooney, A. Parrish, I. Boyd, J.E. Wrotny, R.M. Gomez, J. Koda, M.L. Santee, L. Froidevaux, "Ground-based measurements of ClO from Mauna Kea and intercomparisons with Aura and UARS MLS", Journal of Geophysical Research 116, D02307, doi:10.1029/2010JD014732, 2011. reprint
  6. Pumphrey, H.C., M.L. Santee, N.J. Livesey, M.J. Schwartz, W.G. Read, "Microwave Limb Sounder observations of biomass-burning products from the Australian bush fires of February 2009", Atmospheric Chemistry and Physics 11, 2, 6285-6296, doi:10.5194/acp-11-6285-2011, 2011. reprint
  7. Santee, M.L., G.L. Manney, N.J. Livesey, L. Froidevaux, M.J. Schwartz, W.G. Read, "Trace gas evolution in the lowermost stratosphere from Aura Microwave Limb Sounder measurements", Journal of Geophysical Research 116, D18306, doi:10.1029/2011JD015590, 2011. reprint


  1. Arndt, D.S., M.O. Baringer, M.R. Johnson, "State of the Climate in 2009", Bulletin of the American Meteorological Society 90, S1-S196, doi:10.1175/BAMS-91-7-StateoftheClimate, 2010. reprint
  2. Kuttippurath, J., S. Godin-Beekmann, F. Lefevre, F. Goutail, "Spatial, temporal, and vertical variability of polar stratospheric ozone loss in the Arctic winters 2004/2005-2009/2010", Atmospheric Chemistry and Physics 10, 9915-9930, doi:10.5194/acp-10-9915-2010, 2010. reprint
  3. Santee, M.L., S.P. Sander, N.J. Livesey, L. Froidevaux, "Constraining the chlorine monoxide (ClO) / chlorine peroxide (ClOOCl) equilibrium constant from Aura Microwave Limb Sounder measurements of nighttime ClO", Proceedings of the National Academy of Sciences 107, 15, 6588-6593, doi:10.1073/pnas.0912659107, 2010. reprint


  1. Kuttippurath, J., S. Godin-Beekman, F. Lefevre, A. Pazmino, "Ozone depletion in the Arctic winter 2007-2008", International Journal of Remote Sensing 30, 15-16, 4071-4082, doi:10.1080/01431160902821965, 2009. reprint


  1. Manson, A.H., C.E. Meek, T. Chshyolkova, "Regional stratospheric warmings in the Pacific-Western Canada (PWC) sector during winter 2004/2005: implications for temperatures, winds, chemical constituents and the characterization of the Polar vortex", Annales Geophysicae 26, 3597-3622, doi:10.5194/angeo-26-3597-2008, 2008. reprint
  2. McConnell, J.C., J.J. Jin, "Stratospheric Ozone Chemistry", Atmosphere-Ocean 46, No. 1, 69-92, doi:10.3137/ao.460104, 2008. reprint
  3. Santee, M.L., I.A. MacKenzie, G.L. Manney, M.P. Chipperfield, P.F. Bernath, K.A. Walker, C.D. Boone, L. Froidevaux, N.J. Livesey, J.W. Waters, "A study of stratospheric chlorine partitioning based on new", Journal of Geophysical Research 113, D12307, doi:10.1029/2007JD009057, 2008. reprint
  4. Santee, M.L., A. Lambert, W.G. Read, N.J. Livesey, G.L. Manney, R.E. Cofield, D.T. Cuddy, W.H. Daffer, B.J. Drouin, L. Froidevaux, R.A. Fuller, R.F. Jarnot, B.W. Knosp, V.S. Perun, W.V. Snyder, P.C. Stek, R.P. Thurstans, P.A. Wagner, J.W. Waters, B. Connor, J. Urban, D. Murtagh, P. Ricaud, B. Barrett, A. Kleinboehl, J. Kuttippurath, H. Kullmann, M. von Hobe, G.C. Toon, R.A. Stachnik, "Validation of the Aura Microwave Limb Sounder ClO Measurements", Journal of Geophysical Research 113, D15S22, doi:10.1029/2007JD008762, 2008. reprint


  1. Connor, B.J., T. Mooney, J. Barrett, P. Solomon, A. Parrish, M. Santee, "Comparison of ClO measurements from the Aura Microwave Limb Sounder to ground-based microwave measurements at Scott Base, Antarctica, in spring 2005", Journal of Geophysical Research 112, D24S42, doi:10.1029/2007JD008792, 2007. reprint
  2. Kovalenko, L.J., K.W. Jucks, R.J. Salawitch, G.C. Toon, J-F. Blavier, D.G. Johnson, A. Kleinbohl, N.J. Livesey, J.J. Margitan, H.M. Pickett, M.L. Santee, B. Sen, R.A. Stachnik, J.W. Waters, "Observed and Modeled HOCl Profiles in the Midlatitude Stratosphere: Implication for Ozone Loss", Geophysical Research Letters 34, L19801, doi:10.1029/2007GL031100, 2007. reprint


  1. Barret, B., P. Ricaud, M.L. Santee, J-L. Attie, J. Urban, E. Le Flochmoen, G. Berthet, D. Murtagh, P. Eriksson, A. Jones, J. de La Noe, E. Dupuy, L. Froidevaux, N.J. Livesey, J.W. Waters, M.J. Filipiak, "Intercomparisons of Trace Gas Profiles from the Odin/SMR and Aura/MLS Limb Sounders", Journal of Geophysical Research 111, D21302, doi:10.1029/2006JD007305, 2006. reprint
  2. Cofield, R.E., P.C. Stek, "Design and field-of-view calibration of 114-660 GHz optics of the Earth Observing System Microwave Limb Sounder", IEEE Transactions on Geoscience and Remote Sensing 44, no. 5, 1166-1181, doi:10.1109/TGRS.2006.873234, 2006. reprint
  3. Schoeberl, M.R., S.R. Kawa, A.R. Douglass, T.J. McGee, E.V. Browell, J.W. Waters, N.J. Livesey, W.G. Read, L. Froidevaux, M.L. Santee, H.C. Pumphrey, L.R. Lait, L. Twigg, "Chemical Observations of a Polar Vortex Intrusion", Journal of Geophysical Research 111, D20306, doi:10.1029/2006JD007134, 2006. reprint


  1. Santee, M.L., G.L. Manney, N.J. Livesey, L. Froidevaux, H.C. Pumphrey, W.G. Read, M.J. Schwartz, J.W. Waters, "Polar processing and development of the 2004 Antarctic ozone hole: First results from Aura MLS", Geophysical Research Letters 32, L12817, doi:10.1029/2005GL022582, 2005. reprint


  1. Rex, M., R.J. Salawitch, M.L. Santee, J.W. Waters, K. Hoppel, R. Bevilacqua, "On the unexplained stratospheric ozone losses during cold Arctic Januaries", Geophysical Research Letters 30, 1008, doi:10.1029/2002GL016008, 2003. reprint
  2. Santee, M.L., G.L. Manney, J.W. Waters, N.J. Livesey, "Variations and climatology of ClO in the polar lower stratosphere from UARS MLS measurements", Journal of Geophysical Research 108, D15, 4454, doi:10.1029/2002JD003335, 2003. reprint


  1. Danilin, M.Y., M K.W. Ko, R.M. Bevilacqua, L.V. Lyjak, L. Froidevaux, M.L. Santee, J.M. Zawodny, K.W. Hoppel, E.C. Richard, J.R. Spackman, E.M. Weinstock, R.L. Herman, K.A. McKinney, P.O. Wennberg, F.L. Eisele, R.M. Stimpfle, C.J. Scott, J.W. Elkins, T.V. Bui, "Comparison of ER-2 aircraft and POAM-III, MLS, and SAGE II satellite measurements during SOLVE using traditional correlative analysis and trajectory hunting techniques", Journal of Geophysical Research 107, D5, 8315, doi:10.1029/2001JD000781, 2002. reprint


  1. Drouin, B.J., C.E. Miller, E.A. Cohen, G. Wagner, M. Birk, "Further investigations of the ClO rotational spectrum", Journal of Molecular Spectroscopy 207, 4-9, doi:10.1006/jmsp.2001.8332, 2001. reprint
  2. Huang, F.T., C.A. Reber, "Synoptic estimates of chemically active species and other diurnally varying parameters in the stratosphere, derived from measurements from the Upper Atmosphere Research Satellite (UARS)", Journal of Geophysical Research 106, D2, 1655-1667, doi:10.1029/2000JD900515, 2001. reprint
  3. Wu, J., A.E. Dessler, "Comparisons between measurements and models of Antarctic ozone loss", Journal of Geophysical Research 106, D3, 3195-3201, doi:10.1029/2000JD900606, 2001. reprint


  1. Danilin, M.Y., M.L. Santee, J.M. Rodriguez, M K.W. Ko, J.M. Mergenthaler, J.B. Kumer, A. Tabazadeh, N.J. Livesey, "Trajectory hunting: A case study of rapid chlorine activation in December 1992 as seen by UARS", Journal of Geophysical Research 105, D3, 4003-4018, doi:10.1029/1999JD901054, 2000. reprint
  2. Feist, D.G., C.P. Aellig, N. Kampfer, P.M. Solomon, J.W. Barrett, S. Zoonematkermani, P. Hartogh, C. Jarchow, J.W. Waters, "Validation of stratospheric ClO from the Millimeter-wave Atmospheric Sounder (MAS)", Journal of Geophysical Research 105, D7, 9053-9062, doi:10.1029/1999JD901175, 2000. reprint
  3. Froidevaux, L., J.W. Waters, W.G. Read, P.S. Connell, D.E. Kinnison, J.M. Russell, "Variations in the free chlorine content of the stratosphere (1991-1997): Anthropogenic, volcanic, and methane influences", Journal of Geophysical Research 105, D4, 4471-4481, doi:10.1029/1999JD901039, 2000. reprint
  4. Massie, S.T., X.X. Tie, G.P. Brasseur, R.M. Bevilacqua, M.D. Fromm, M.L. Santee, "Chlorine activation during the 1995-1996 Arctic winter", Journal of Geophysical Research 105, D6, 7111-7131, doi:10.1029/1999JD901035, 2000. reprint
  5. Ricaud, P., M.P. Chipperfield, J.W. Waters, J.M. Russell, A.E. Roche, "Temporal evolution of chlorine monoxide in the middle stratosphere", Journal of Geophysical Research 105, D4, 4459-4469, doi:10.1029/1999JD900995, 2000. reprint
  6. Santee, M.L., G.L. Manney, N.J. Livesey, J.W. Waters, "UARS Microwave Limb Sounder Observations of Denitrification and Ozone Loss in the 2000 Arctic Late Winter", Geophysical Research Letters 27, 3213-3216, doi:10.1029/2000GL011738, 2000. reprint
  7. van den Broek, M W.P., A. Bregman, J. Lelieveld, "Model study of stratospheric chlorine activation and ozone loss during 1996/1997 winter", Journal of Geophysical Research 105, D23, 28,961-29,977, doi:10.1029/2000JD900294, 2000. reprint


  1. Khattatov, B.V., J.C. Gille, L.V. Lyjak, G.P. Brasseur, V.L. Dvortsov, A.E. Roche, J.W. Waters, "Assimilation of photochemically active species and a case analysis of UARS data", Journal of Geophysical Research 104, D15, 18,715-18,737, doi:10.1029/1999JD900225, 1999. reprint
  2. Randel, W.J., F. Wu, J.M. Russell, J. Waters, "Space-time patterns of trends in stratospheric constituents derived from UARS measurements", Journal of Geophysical Research 104, D3, 3711-3727, doi:10.1029/1998JD100044, 1999. reprint
  3. Solomon, S., "Stratospheric ozone depletion: A review of concepts and history", Reviews of Geophysics 37, 275-316, doi:10.1029/1999RG900008, 1999. reprint
  4. Stachnik, R.A., R.J. Salawitch, A. Engel, U. Schmidt, "Measurements of chlorine partitioning in the winter Arctic stratosphere", Geophysical Research Letters 26, 3093-3096, doi:10.1029/1999GL010817, 1999. reprint


  1. Dessler, A.E., M.D. Burrage, J-U. Grooss, J.R. Holton, J.L. Lean, S.T. Massie, M.R. Schoeberl, A.R. Douglass, C.H. Jackman, "Selected science highlights from the first 5 years of the Upper Atmosphere Research Satellite (UARS) program", Reviews of Geophysics 36, 183-210, doi:10.1029/97RG03549, 1998. reprint
  2. Khosravi, R., G.P. Brasseur, A. Smith, D.W. Rusch, J.W. Waters, J.M. Russell, "Significant Reduction in Stratospheric Ozone Deficit using a 3-D Model Constrained with UARS Data", Journal of Geophysical Research 103, D13, 16,203-16,219, doi:10.1029/98JD01084, 1998. reprint
  3. Ricaud, P., E. Monnier, F. Goutail, J.P. Pommereau, C. David, S. Godin, L. Froidevaux, J.W. Waters, J. Mergenthaler, A.E. Roche, H. Pumphrey, M.P. Chipperfield, "Stratosphere over Dumont d", Journal of Geophysical Research 103, D11, 13267-13284, doi:10.1029/98JD00689, 1998. reprint
  4. Searle, K.R., M.P. Chipperfield, S. Bekki, J.A. Pyle, "The impact of spatial averaging on calculated polar ozone loss: 1. Model experiments", Journal of Geophysical Research 103, D19, 25,397-25,408, doi:10.1029/98JD02090, 1998. reprint
  5. Siskind, D.E., L. Froidevaux, J.M. Russell, J. Lean, "Implications of upper stratospheric trace constituent changes observed by HALOE for O3 and ClO from 1992 to 1995", Geophysical Research Letters 25, 3513-3516, doi:10.1029/98GL02664, 1998. reprint


  1. Engel, A., U. Schmidt, R.A. Stachnik, "Partitioning Between Chlorine Reservoir Species Deduced from Observations in the Arctic Winter Stratosphere", Journal of Atmospheric Chemistry 27, 107-126, doi:10.1023/A:1005781919448, 1997. reprint
  2. Lutman, E.R., J.A. Pyle, M.P. Chipperfield, D.J. Lary, I. Kilbane-Dawe, J.W. Waters, N. Larsen, "Three dimensional studies of the 1991/92 Northern Hemisphere winter using domain-filling trajectories with chemistry", Journal of Geophysical Research 102, D1, 1479-1488, doi:10.1029/96JD00698, 1997. reprint
  3. Osterman, G.B., R.J. Salawitch, B. Sen, G.C. Toon, R.A. Stachnik, H.M. Pickett, J.J. Margitan, J-F. Blavier, D.B. Peterson, "Balloon-borne measurements of stratospheric radicals and their precursors: Implications for the production and loss of ozone", Geophysical Research Letters 24, 1107-1110, doi:10.1029/97GL00921, 1997. reprint
  4. Santee, M.L., G.L. Manney, L. Froidevaux, R.W. Zurek, J.W. Waters, "MLS observations of ClO and HNO3 in the 1996-97 Arctic polar vortex", Geophysical Research Letters 24, 2713-2716, doi:10.1029/97GL52830, 1997. reprint


  1. Aellig, C.P., N. Kampfer, C. Rudin, R.M. Bevilacqua, W. Degenhardt, P. Hartogh, C. Jarchow, K. Kunzi, J.J. Olivero, C. Croskey, J.W. Waters, H.A. Michelsen, "Latitudinal distribution of upper stratospheric ClO as derived from space borne microwave spectroscopy", Geophysical Research Letters 23, 2321-2324, doi:10.1029/96GL01215, 1996. reprint
  2. Chance, K., W.A. Traub, D.G. Johnson, K.W. Jucks, P. Ciarpallini, R.A. Stachnik, R.J. Salawitch, H.A. Michelsen, "Simultaneous measurements of stratospheric HOx, NOx and Clx: Comparsion with a photochemical model", Journal of Geophysical Research 101, D4, 9031-9043, doi:10.1029/96JD00064, 1996. reprint
  3. Chipperfield, M.P., M.L. Santee, L. Froidevaux, G.L. Manney, W.G. Read, J.W. Waters, A.E. Roche, J.M. Russell, "Analyses of UARS data in the southern polar vortex in September 1992 using a chemical transport model", Journal of Geophysical Research 101, D13, 18861-18881, doi:10.1029/96JD00936, 1996. reprint
  4. Dessler, A.E., S.R. Kawa, A. Douglass, D.B. Considine, J.B. Kumer, A.E. Roche, J.W. Waters, J.M. Russell, J.C. Gille, "A test of the partitioning between ClO and ClONO2 using simultaneous UARS measurements of ClO, NO2 and ClONO2", Journal of Geophysical Research 101, D7, 12515-12521, doi:10.1029/96JD00695, 1996. reprint
  5. Dessler, A.E., S.R. Kawa, D.B. Considine, J.W. Waters, L. Froidevaux, J.B. Kumer, "UARS measurements of ClO and NO2 at 40 and 46 km and implications for the 'ozone deficit'", Geophysical Research Letters 23, 339-342, doi:10.1029/96GL00154, 1996. reprint
  6. Jucks, K.W., D.G. Johnson, K.V. Chance, W.A. Traub, R.J. Salawitch, R.A. Stachnik, "Ozone Production and loss rate measurements in the middle stratosphere", Journal of Geophysical Research 101, D22, 28785-28792, doi:10.1029/96JD02739, 1996. reprint
  7. Santee, M.L., L. Froidevaux, G.L. Manney, W.G. Read, J.W. Waters, M.P. Chipperfield, A.E. Roche, J.B. Kumer, J.L. Mergenthaler, J.M. Russell, "Chlorine deactivation in the lower stratospheric polar regions during late winter: Results from UARS", Journal of Geophysical Research 101, D13, 18835-18859, doi:10.1029/96JD00580, 1996. reprint
  8. Schoeberl, M.R., A.R. Douglass, S.R. Kawa, A.E. Dessler, P.A. Newman, R.S. Stolarski, A.E. Roche, J.W. Waters, J.M. Russell, "The development of the Antarctic ozone hole", Journal of Geophysical Research 101, D15, 20,909-20,924, doi:10.1029/96JD01707, 1996. reprint
  9. Waters, J.W., W.G. Read, L. Froidevaux, T.A. Lungu, V.S. Perun, R.A. Stachnik, R.F. Jarnot, R.E. Cofield, E.F. Fishbein, D.A. Flower, J.R. Burke, J.C. Hardy, L.L. Nakamura, B.P. Ridenoure, Z. Shippony, R.P. Thurstans, L.M. Avallone, D.W. Toohey, R.L. de Zafra, D.T. Shindell, "Validation of UARS Microwave Limb Sounder ClO measurements", Journal of Geophysical Research 101, D6, 10,091-10,127, doi:10.1029/95JD03351, 1996. reprint


  1. Crewell, S., R. Fabian, K. Kunzi, H. Nett, T. Wehr, W. Read, J. Waters, "Comparison of ClO measurements made by airborne and spaceborne microwave radiometers in the Arctic winter stratosphere 1993", Geophysical Research Letters 22, 1489-1492, doi:10.1029/95GL01390, 1995. reprint
  2. Dessler, A.E., D.B. Considine, G.A. Morris, M.R. Schoeberl, A.E. Roche, J. Mergenthaler, J.M. Russell, J.W. Waters, J. Gille, G.K. Yue, "Correlated observations of HCl and ClONO2 from UARS and implications for stratospheric chlorine partitioning", Geophysical Research Letters 22, 1721-1724, doi:10.1029/95GL01593, 1995. reprint
  3. Douglass, A.R., M.R. Schoeberl, R.S. Stolarski, J.W. Waters, J.M. Russell, A.E. Roche, "Interhemispheric differences in springtime production of HCl and ClONO2 in the polar vortices", Journal of Geophysical Research 100, D7, 13967-13978, doi:10.1029/95JD00698, 1995. reprint
  4. Eckman, R.S., W.L. Grose, R.E. Turner, W.T. Blackshear, J.M. Russell, L. Froidevaux, J.W. Waters, J.B. Kumer, A.E. Roche, "Stratospheric trace constituents simulated by a three-dimensional general circulation model: Comparison with UARS data", Journal of Geophysical Research 100, D7, 13951-13966, doi:10.1029/95JD01278, 1995. reprint
  5. Fahey, D.W., G. Braathen, D. Cariolle, Y. Kondo, W.A. Matthews, M.J. Molina, J.A. Pyle, R.B. Rood, J.M. Russell, U. Schmidt, D.W. Toohey, J.W. Waters, C.R. Webster, S.C. Wofsy, "Polar Ozone", Scientific Assessment of Stratospheric Ozone 1994, ch.4, 1995.
  6. Geller, M.A., V. Yudin, A.R. Douglass, J.W. Waters, L.S. Elson, A.E. Roche, J.M. Russell, "UARS PSC, ClONO2, HCl, and ClO measurements in early winter: Additional verification of the paradigm for chlorine activation", Geophysical Research Letters 22, 2937-2940, doi:10.1029/95GL01661, 1995. reprint
  7. Johnson, D.G., W. Traub, K. Chance, K. Jucks, R.A. Stachnik, "Estimating the abundance of ClO from simultaneous remote sensing measurements of stratospheric HOx, NOx and Clx", Geophysical Research Letters 22, 1869-1871, doi:10.1029/95GL01249, 1995. reprint
  8. Manney, G.L., R.W. Zurek, L. Froidevaux, J.W. Waters, "Evidence for arctic ozone depletion in late February and early March 1994", Geophysical Research Letters 22, 2941-2944, doi:10.1029/95GL02229, 1995. reprint
  9. Pyle, J.A., M.P. Chipperfield, I. Kilbane-Dawe, A.M. Lee, R.M. Stimpfle, D. Kohn, W. Renger, J.W. Waters, "Early modelling results from the SESAME and ASHOE campaigns", Faraday Discussion Articles 100, 371-387, 1995.
  10. Ricaud, P.D., E.S. Carr, R.S. Harwood, W.A. Lahoz, L. Froidevaux, W.G. Read, J.W. Waters, J.L. Mergenthaler, J.B. Kumer, A.E. Roche, G.E. Peckham, "Polar stratospheric clouds as deduced from MLS and CLAES measurements", Geophysical Research Letters 22, 2033-2036, doi:10.1029/95GL00479, 1995. reprint
  11. Santee, M.L., W.G. Read, J.W. Waters, L. Froidevaux, G.L. Manney, D.A. Flower, R.F. Jarnot, R.S. Harwood, G.E. Peckham, "Interhemispheric differences in polar stratospheric HNO3, H2O, ClO and O3", Science 267, 849-852, doi:10.1126/science.267.5199.849, 1995. reprint
  12. Waters, J.W., G.L. Manney, W.G. Read, L. Froidevaux, D.A. Flower, R.F. Jarnot, "UARS MLS observations of lower stratospheric ClO in the 1992-93 and 1993-94 arctic winter vortices", Geophysical Research Letters 22, 823-826, doi:10.1029/95GL00083, 1995. reprint


  1. Bell, W., N.A. Martin, T.D. Gardiner, N.R. Swann, P.T. Woods, P.F. Fogal, J.W. Waters, "Column measurements of stratospheric trace species over Are, Sweden in the winter of 1991-1992", Geophysical Research Letters 21, 1347-1350, doi:10.1029/93GL01206, 1994. reprint
  2. Lefevre, F., G.P. Brasseur, I. Folkins, A.K. Smith, P. Simon, "Chemistry of the 1991-1992 stratospheric winter: Three-dimensional model simulations", Journal of Geophysical Research 99, D4, 8183-8195, doi:10.1029/93JD03476, 1994. reprint
  3. Manney, G.L., L. Froidevaux, J.W. Waters, R.W. Zurek, W.G. Read, L.S. Elson, J.B. Kumer, J.L. Mergenthaler, A.E. Roche, A. O'Neill, R.S. Harwood, I. MacKenzie, R. Swinbank, "Chemical depletion of ozone in the Arctic lower stratosphere during winter 1992-93", Nature 370, 429-434, doi:10.1038/370429a0, 1994. reprint
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  1. Chipperfield, M., "Satellite maps ozone destroyer", Nature 362, 592-593, doi:10.1038/362592a0, 1993. reprint
  2. Douglass, A., R. Rood, J. Waters, L. Froidevaux, W. Read, L. Elson, M. Geller, Y. Chi, M. Cerniglia, S. Steenrod, "A 3D simulation of the early winter distribution of reactive chlorine in the north polar vortex", Geophysical Research Letters 20, 1271-1274, doi:10.1029/93GL01586, 1993. reprint
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  1. Stachnik, R.A., J.C. Hardy, J.A. Tarsala, J.W. Waters, N.R. Erickson, "Submillimeterwave heterodyne measurements of stratospheric ClO, HCl, O3, and HO2: First results", Geophysical Research Letters 19, 1931-1934, doi:10.1029/92GL01884, 1992. reprint


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  1. Waters, J.W., J.J. Gustincic, R.K. Kakar, H.K. Roscoe, P.N. Swanson, T.G. Phillips, T. DeGraauw, A.R. Kerr, R.J. Mattauch, "Aircraft search for millimeter wavelength emission by stratospheric ClO", Journal of Geophysical Research 84, 7034-7040, doi:10.1029/JC084iC11p07034, 1979. reprint

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