Measurements of Methanethiol (MeSH) and dimethyl sulfide (DMS) in surface seawater digitalised from AMT-7 1998.

Global emissions of methanethiol are highly uncertain and the drivers influencing its seawater concentrations are quasi unexplored. Here we have digitalised measurements from 1998 taken during AMT-7 (Atlantic Meridional Transect), which may be useful for future investigators. The measurements are originally presented in the following reference:

Kettle, A. J., Rhee, T. S., von Hobe, M., Poulton, A., Aiken, J., and Andreae, M. O.: Assessing the flux of different volatile sulfur gases from the ocean to the atmosphere, J. Geophys. Res., 106, 12193–12209, https://doi.org/10.1029/2000JD900630, 2001.

Measurements from AMT-7 were extracted from the graphs in the manuscript using an image extraction technique (https://apps.automeris.io/wpd/, last accessed July 2024). To ensure concurrency of the measurements and deal with the error in the time stamp related to the use of an image extraction technique, data from AMT-7 was binned in 6-hourly bins. Data gaps are listed with an improbable number of -999.

Definitions of acronyms, site abbreviations, or other project-specific designations:

Lat=latitude (negative indicates south)

Lon=longitude (negative indicates west)

t_Kettle01 = The mean measured concentration during each 6 hour bin is shown, 3 hours either side of the listed time. The timestamp indicates sampling time in local solar time, expressed as DD/MM/YYYY HH:MM

MeSH_nM= methanethiol surface seawater concentration in nM, defined as nmol dm^(-3)

DMS_nM= dimethyl sulfide surface seawater concentration in nM, defined as nmol dm^(-3)

Chla_mg_m3 = surface chlorophyll a concentration in mg m^(-3)

SST_C= sea surface temperature in degrees Celsius

SSS_PSU= sea surface salinity in practical salinity units (PSU)