The POLAR-CHANGE cruise was conducted in February and March 2023 on board the BIO RV Hesperides A33 near the Antarctic Peninsula and in the Weddell Sea. A Vocus PTR (Aerodyne Research, SN P4Q-171) was used to measure air concentrations of MeSH and DMS. Vocus PTR data was acquired at 1 sec time resolution and averaged to one hour in post-processing. A fast polarity switching time-of-flight chemical ionization mass spectrometer (Vocus B, Aerodyne Research, SN P4B-002) running with benzene cation chemistry was also used to measure DMS. Vocus B data was acquired at 2 sec time resolution and averaged to one hour in post-processing. There was good agreement between the DMS measured with the Vocus PTR and with the Vocus B. This dataset contains air concentrations of MeSH and DMS as a function of lat/lon, as well as relevant auxiliary data (air temperature and pressure).

Definitions:

Start_Time_UTC = The start time in UTC for each 1 hour average as DD/MM/YYYY HH:MM

Lat = latitude in degrees (negative indicates south)

Lon = longitude in degrees (negative indicates west)

MeSH_ppbv = methanethiol air concentration in parts per billion by volume

DMS_ppbv_PTR = dimethyl sulfide air concentration in parts per billion by volume measured with the Vocus PTR

DMS_ppbv_B = dimethyl sulfide air concentration in parts per billion by volume measured with the Vocus B

Temp_C = air temperature in degrees Celsius

Press_hPa = ambient pressure in hectopascal