The Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) version 4.1 retrievals: Trends and seasonal distributions

The Atmospheric Chemistry Experiment (ACE) satellite measures infrared transmission spectra of the atmosphere with a Fourier Transform Spectrometer (FTS) using the Sun as a light source. ACE provides a global view of atmospheric composition from altitude profiles of volume mixing ratios of 44 molecules starting in February 2004. The current version of ACE-FTS processing is 4.1 released in July 2020. Compared to v.4.0, the trends and altitude-latitude distributions have changed only slightly. Quarterly altitude-latitude distributions have been computed to highlight seasonal effects. Generally, the tropospheric volume mixing ratios of v.4.1 agree well with surface measurements made by the NOAA (National Oceanic and Atmospheric Administration) flask network and the AGAGE network. The revised ACE trends provide a quantitative state-of-the-atmosphere report. (C) 2020 Elsevier Ltd. All rights reserved.