This dataset comprises a ship-based continuous underway surface seawater dimethylsulfide (DMS) concentration timeseries, with ancillary in-situ mesaurements. Measurements were collected in the southeast Atlantic sector of the Southern Ocean from October 18 to November 18, 2019. A mini Atmospheric Pressure Chemical Ionisation Mass Spectrometer (AP-CIMS) measurement system, coupled to a segmented flow coil equilibrator, were used to continuously measure nanomolar (nM) DMS in water collected from the ship's underway seawater supply at 5 metres depth. The aim was to understand and quantify the production of aerosols derived from marine biogenic trace gas emissions in the Southern Ocean during the springtime onset of sea ice melt. The sampling campaign was part of the wider South African-led SCALE (Southern oCean seAsonaL Experiment) project (http://scale.org.za/). In-situ sampling and data post-processing was conducted by the ship-based Team Leader, George Manville. Land-based supervision was provided by the Principal Investigator, Tom Bell. This work was funded by the NERC Grant NE/R007586/1.
