Open AccessValidation of CFC‐12 measurements from the Improved Limb Atmospheric Spectrometer (ILAS) with the version 6.0 retrieval algorithm
Author(s) -
Khosrawi F.,
Müller R.,
Irie H.,
Engel A.,
Toon G. C.,
Sen B.,
Aoki S.,
Nakazawa T.,
Traub W. A.,
Jucks K. W.,
Johnson D. G.,
Oelhaf H.,
Wetzel G.,
Sugita T.,
Kanzawa H.,
Yokota T.,
Nakajima H.,
Sasano Y.
Publication year - 2004
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 - 10.1029/2003jd004325
Subject(s) - altitude (triangle) , spectrometer , remote sensing , environmental science , balloon , satellite , atmospheric sounding , northern hemisphere , southern hemisphere , imaging spectrometer , meteorology , atmospheric sciences , physics , geology , optics , mathematics , climatology , geometry , medicine , astronomy , cardiology
Measurements of CFC‐12 were made by the Improved Limb Atmospheric Spectrometer (ILAS) between 57°N and 72°N in the Northern Hemisphere and between 64°S and 89°S in the Southern Hemisphere. ILAS was launched on 17 August 1996 on board the Advanced Earth Observing Satellite (ADEOS). The ILAS validation balloon campaigns were carried out from Kiruna, Sweden (68°N, 21°E), in February and March 1997 and from Fairbanks, Alaska (65°N, 148°W), in April and May 1997. During these validation balloon campaigns, CFC‐12 was measured with the in situ instruments ASTRID, BONBON, and SAKURA and the remote sensing spectrometers MIPAS‐B, FIRS‐2, and MkIV. ILAS version 6.0 CFC‐12 profiles obtained at the nearest location to the validation balloon measurement are compared with these validation balloon measurements. The quality of ILAS CFC‐12 data processed with the version 6.0 algorithm improved significantly compared to previous versions. Low relative differences between ILAS CFC‐12 and the correlative measurements of about 10% were found between 13 and 20 km. The comparison of vertical profiles shows that ILAS CFC‐12 data are useful below about 20–22 km inside the vortex and below about 25 km outside the vortex. However, at greater altitudes the relative percentage difference increases very strongly with increasing altitude. Further, correlations of CFC‐12 with N 2 O show a good agreement with the correlative measurements for N 2 O values of N 2 O > 150 ppbv. In summary, ILAS CFC‐12 data are now suitable for scientific studies in the lower stratosphere.