Trends and drivers of CO2 parameters, from 2006 to 2021, at a time-series station in the Eastern Tropical Atlantic (6°S, 10°W)

• DOI: 10.3389/fmars.2024.1299071
• Publication Date: 2024-02-19T04:45:37Z
• Authors: Nathalie Lefèvre; Doris Veleda; Laurence Beaumont
• Keywords: Alkalinity; Mooring; Tropical Atlantic; Fugacity

The seawater fugacity of CO 2 ( f ) has been monitored hourly at an instrumented mooring 6°S, 10°W since 2006. is located in the South Equatorial Current and affected by equatorial Atlantic cold tongue. This site characterized large seasonal sea surface temperature variations (>4°C). measured a spectrophotometric sensor deployed about 1.5 meters deep. Measurements , (SST) salinity (SSS) are used to calculate total dissolved inorganic carbon (TCO pH. Total alkalinity (TA) calculated using empirical relationship with SSS determined for this region. Satellite chlorophyll-a concentrations low (<0.2 mg m -3 but some peaks over 0.8 sometimes detected August. Nevertheless, permanent source atmosphere, averaging 4.7 ± 2.4 mmol -2 d -1 2006-2021. Despite weakening wind, flux increases significantly 0.20 0.05 yr . suggests that increasing explained faster than atmospheric increase during Most driven TCO followed SST. leads pH decrease -0.0030 0.0004 SST anomalies (SSTA) correlated Tropical Southern (TSA) index 3 region (ATL3) correlation coefficient higher 0.75. strong positive phase both ATL3 TSA, observed towards end time-series, likely contributing