Physico-chemical parameters of seawater during the exposure of the marine calanoid copepod Acartia tonsa to hypoxia and marine heatwave events

Specimens of the marine calanoid copepod Acartia tonsa were exposed for five days under laboratory conditions to the isolated or combined effects of hypoxia and a marine heatwave event to test for their sex-specific life-history and physiological responses to these stressors. Four treatments were used: Control (C: 18 °C, 100 % O₂ sat.), Hypoxia (H: 18 °C, 35 % O₂ sat.), marine heatwave (MHW: 25 °C, 100 % O₂ sat.) and combined conditions (HMHW: 25 °C, 35 % O₂ sat.). This dataset compiles the physico-chemical parameters of the seawater (i.e. temperature, oxygen saturation, pH and salinity) in the aquaria holding the copepods during the five-day exposure experiment.