Dataset: CTD data collected in the Guaymas Basin, Gulf of California from R/V Atlantis cruise AT42-05 in 2018 and R/V Falkor cruise FK190211 in 2019

Data processed using Sea-Bird’s SBE Data Processing program/SeaSoft, version 7.23.2

Data processing protocol adapted from CalCOFI methods, found here: https://calcofi.org/data/ctd/165-ctd-processing/330-ctd-data-processing-protocol.html

Raw .hex files were converted to ASCII .cnv files without skipping scans; hysteresis correction was applied to oxygen data. A 9 s median window filter applied to all variables, and a 0.15 low pass filter was applied to pressure data only. A 4 s delay was applied to the raw oxygen data and v1 (also oxygen) as recommended in Sea-Bird’s software manual. Default settings were used for the cell thermal mass correction. Depth, potential temperature, salinity, density, oxygen concentration (tau correction applied), oxygen saturation, dynamic meters, and specific volume anomaly were derived from existing data using the EOS-8 option in SeaSoft.

Casts were not split or binned, because these steps obscure or eliminate the hydrothermal plume signal seen in the temperature data at the bottom depths of the casts.

Files were converted to .csv format using the text to column function in Microsoft Excel.