The Portable Atmospheric Measurement box On Sea (PAMOS) is a fully automated instrument designed for air monitoring on commercial vessels, requiring no maintenance from the crew. First prototypes were deployed on the MS Fridtjof Nansen, a cruise ship operated by HX, in 2024. PAMOS unit 003 was installed on the MS Fridtjof Nansen for the Antarctic season and collected data south of 60°S on eleven round trips between Ushuaia and the Antarctic Peninsula from 30 November 2024 to 26 March 2025. The datasets include GPS positions (from both PAMOS and the vessel's navigation system when available), meteorological parameters (air temperature, pressure, relative humidity, relative wind speed and direction, and precipitation measured with a Vaisala WXT536), aerosol properties (particle number concentration from a naneos Partector 2, black carbon from a MA350, and particulate matter from an OPC-R2), and trace gases (CO₂, CO, CH₄, SO₂ from smartgas sensors). Quality flags are provided for all parameter groups and should be considered when using the data.

Data processing was carried out with the Python package shipspy [1], as described in [2].[1] Köhler, L. (2025). shipspy (Version 1.1.0) [Computer software]. https://github.com/shipspy-development/shipspy[2] Köhler, L. (2025). PAMOS processing (Version 1.0.0) [Computer software]. https://github.com/LauraKoehler/pamos_processing.git