Table 1.

Key environmental and biogeochemical parameters in experimental pH zones in the north and south

pH zone	Temp, C	pHT	TA	pCO2	HCO3−	CO32−	Ωcalcite
Ambient, N	23.4 ± 0.7	8.0 ± 0.1	2,563 ± 3	568 ± 100	2,059 ± 54	202 ± 22	4.8 ± 0.5
Ambient, S	19.6 ± 1.5	8.1 ± 0.1	2,563 ± 2	440 ± 192	2,016 ± 71	219 ± 29	5.1 ± 0.7
Low, N	23.8 ± 0.7	7.8 ± 0.2	2,560 ± 7	1,075 ± 942	2,180 ± 115	150 ± 47	3.5 ± 1.1
Low, S	17.5 ± 2.8	7.8 ± 0.3	2,560 ± 7	1,581 ± 2,711	2,232 ± 136	128 ± 56	3.0 ± 1.3
Extreme low, N	23.4 ± 0.7	7.2 ± 0.4	2,559 ± 13	6,590 ± 21,352	2,428 ± 85	54 ± 35	1.3 ± 0.8
Extreme low, S	17.5 ± 2.8	6.6 ± 0.5	2,563 ± 13	23,989 ± 16,638	2,508 ± 100	21 ± 41	0.5 ± 0.9

The pH and temperature estimates are based on hourly measurements from in situ pH meters taken during separate deployments for N and S sites [N = 604 (north) −3162 (south)]. Total alkalinity (TA) and salinity estimates (mean 38 ppm) are from discrete water samples taken throughout sensor deployments (n = 3–10), and all other carbonate parameters are estimated by assuming constant TA and salinity and applying the mean TA and salinity values to pH and temperature values measured by in situ sensors. Differences in temperature between sites are due to deployment times: early summer (north) and early fall (south). Values are means ± SD. TA, HCO₃⁻, CO₃²⁻ are reported in µmol⋅kg⁻¹.