Table 1. Chemical characteristics of seawater from the experimental treatments, field measurements made at two McMurdo Sound locations, and relevant polar studies.
| ExperimentElevated pH pH 8.316±0.001 | ExperimentAntarctic control pH 7.993±0.002 | ExperimentLowered pH pH 7.775±0.002 | Field Granite Harbour pH 8.024 | Field New Harbour pH 7.996±0.007 | Cape Armitage pH 8.0 [23] | Arctic Fjord pH 8.12 [21] | Arctic Fjord pH 7.78 [21] | Artificial seawater pH 7.4 [9] | Artificial seawater pH 8.2 [9] | |
| pCO2 ppm (c) | 186.5+0.3 | 429.5+0.8 | 734.6+0.9 | 410 | 439.6±6.9 | nr | 320 | 765 | nr | nr |
| AT µmol kg−1 | 2253.2±3.9 | 2256.5±3.9 | 2258.3±2.8 | 2338.6 | 2329±2.8 | 2336 (c) | 2312 | 2295 | 2558 | 2678 |
| CT µmol kg−1 | 2043.7±3.7 (c) | 2169.4±3.9 (c) | 2235.0±2.8 (c) | 2238.2 | 2238.1±2.3 | nr | 2148 (c) | 2237 (c) | nr | nr |
| ΩAr (c) | 2.178±0.004 | 1.133±0.002 | 0.710±0.001 | 1.261 | 1.18±0.02 | 1.03 | 1.81 | 1.0 | 0.47 | 2.66 |
| [CO3 2−] µmol kg−1 (c) | 144.0±0.3 | 74.9±0.1 | 47.0±0.1 | 83.5 | 78.4±1.2 | nr | nr | nr | nr | nr |
| Temperature (°C) | −1.76±0.001 | −1.76±0.001 | −1.76±0.001 | −1.92 | −1.92 | −1.9 | 2.2 | 5.0 | 4.0 | 4.0 |
| Salinity (ppt) | 34.1 | 34.1 | 34.1 | 34.6 | 34.6 | 34.6 | 34.9 | 34.8 | 35 | 35 |
Values from this study are mean ± standard errors. AT = average total alkalinity, CT = total dissolved CO2, ΩAr = aragonite saturation index. (c) indicates calculated values, all other values are measured, nr = not reported. pH on the total hydrogen scale except for [23] ( = NBS scale) and [9] ( = not specified).