Preface to special section on ILAS‐II: The Improved Limb Atmospheric Spectrometer–II

Abstract

The Improved Limb Atmospheric Spectrometer–II (ILAS‐II) was a solar‐occultation satellite sensor designed to measure minor constituents associated with polar ozone depletion. ILAS‐II was placed on board the Advanced Earth Observing Satellite–II (ADEOS‐II, “Midori‐II”), which was successfully launched on 14 December 2002 from the Tanegashima Space Center of the Japan Aerospace Exploration Agency (JAXA). After an initial check of the instruments, ILAS‐II made routine measurements for about 7 months, from 2 April 2003 to 24 October 2003, a period that included the formation and collapse of an Antarctic ozone hole in 2003, one of the largest in history. This paper introduces a special section containing papers on ILAS‐II instrumental and on‐orbit characteristics, several validation results of ILAS‐II data processed with the version 1.4 data processing algorithm, and scientific analyses of polar stratospheric chemistry and dynamics using ILAS‐II data.