Table 1.

Seawater pH statistics for pH zones associated with CO₂ vents at Ischia, Italy, calculated from hourly measurements taken by in situ pH sensors for separate deployments of the sensors

	pH Zone
Season/site	Ambient	Low	Extreme low
Winter/south
Mean	—	7.71 ± 0.39	6.56 ± 0.49
CV	—	0.05	0.08
N	—	646	646
Spring/south
Mean	8.07 ± 0.09	7.75 ± 0.31	6.51 ± 0.42
CV	0.01	0.04	0.06
N	792	1,801	1,801
Fall/north
Mean	7.96 ± 0.06	7.47 ± 0.19	7.21 ± 0.34
CV	0.01	0.03	0.05
N	602	602	602
Fall/south
Mean	8.04 ± 0.09	7.84 ± 0.24	6.78 ± 0.67
CV	0.01	0.03	0.10
N	712	216	712

Statistics are mean ± SD. CV, coefficient of variation.