The purpose of the special issue (SI) is the collection of relevant contributions on the detection, analysis, and prediction of long-term changes and trends of trace gases and physical parameters of the atmosphere from the upper troposphere up into the ionosphere as presented at the TRENDS2022 workshop (11th International Workshop on Long-Term Changes and Trends in the Atmosphere). The SI will be open for contributions to the TRENDS2022 conference and co-located SPARC LOTUS and SPARC ATC working group meetings, as well as for other publications directly related to the scope of the SI.