Supplement to: Nunes, Joana; McCoy, Sophie J; Findlay, Helen S; Hopkins, Frances E; Kitidis, Vassilis; Queirós, Ana M; Rayner, Lucy; Widdicombe, Stephen (2016): Two intertidal, non-calcifying macroalgae (Palmaria palmata and Saccharina latissima) show complex and variable responses to short-term CO2 acidification. ICES Journal of Marine Science, 73(3), 887-896, https://doi.org/10.1093/icesjms/fsv081