Open AccessThe budget and partitioning of stratospheric chlorine during the 1997 Arctic summer
Author(s) -
Sen B.,
Osterman G. B.,
Salawitch R. J.,
Toon G. C.,
Margitan J. J.,
Blavier J.F.,
Chang A. Y.,
May R. D.,
Webster C. R.,
Stimpfle R. M.,
Bonne G. P.,
Voss P. B.,
Perkins K. K.,
Anderson J. G.,
Cohen R. C.,
Elkins J. W.,
Dutton G. S.,
Hurst D. F.,
Romashkin P. A.,
Atlas E. L.,
Schauffler S. M.,
Loewenstein M.
Publication year - 1999
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999jd900245
Subject(s) - chlorine , mixing ratio , chemistry , jet propulsion , stratosphere , ozone , atmospheric chemistry , decomposition , arctic , atmospheric sciences , analytical chemistry (journal) , environmental chemistry , geology , organic chemistry , thermodynamics , physics , oceanography
Volume mixing ratio profiles of HCl, HOCl, ClNO 3 , CH 3 Cl, CFC‐12, CFC‐11, CCl 4 , HCFC‐22, and CFC‐113 were measured simultaneously from 9 to 38 km by the Jet Propulsion Laboratory MkIV Fourier Transform Infrared solar absorption spectrometer during two balloon flights from Fairbanks, Alaska (64.8°N), on May 8 and July 8, 1997. The altitude variation of total organic chlorine (CCl y ), total inorganic chlorine (Cl y ), and the nearly constant value (3.7±0.2 ppbv) of their sum (Cl TOT ) demonstrates that the stratospheric chlorine species available to react with O 3 are supplied by the decomposition of organic chlorinated compounds whose abundances are well quantified. Measured profiles of HCl and ClNO 3 agree well with profiles found by photochemical model (differences <10% for altitudes below 35 km) constrained by various other constituents measured by MkIV. The production of HCl by ClO + OH plays a relatively small role in the partitioning of HCl and ClNO 3 for the sampled air masses. However, better agreement with the measured profiles of HCl and ClNO 3 is obtained when this source of HCl is included in the model. Both the measured and calculated [ClNO 3 ]/[HCl] ratios exhibit the expected near linear variation with [O 3 ] 2 /[CH 4 ] over a broad range of altitudes. MkIV measurements of HCl, ClNO 3 , and CCl y agree well with ER‐2 in situ observations of these quantities for directly comparable air masses. These results demonstrate good understanding of the budget of stratospheric chlorine and that the partitioning of inorganic chlorine is accurately described by photochemical models that employ JPL97 reaction rates and production of HCl from ClO + OH for the environmental conditions encountered: relatively warm temperatures, long periods of solar illumination, and relatively low aerosol surface areas.