Recent observations and modelling studies suggest that eutrophication-related biogeochemical changes can mask atmospheric CO2-induced pH decreases. Data collected by the Dutch monitoring authorities in different coastal systems (North Sea, Wadden Sea, Ems-Dollard, Eastern Scheldt and Scheldt estuary) since 1975 provide an excellent opportunity to test whether this is the case in the Dutch coastal zone. The time-series were analysed using Multi-Resolution Analysis (MRA) which resulted in the identification of system-dependent patterns on both seasonal and intra-annual time scales. The observed rates of change greatly exceed those expected from enhanced CO2 uptake, thus confirming that eutrophication can play a dominant role in ocean acidification.
Provoost, P., van Heuven, S., Soetaert, K., Laane, R., & Middelburg, J. J., 2010. Long-term record of pH in the Dutch coastal zone: a major role for eutrophication-induced changes. Biogeosciences Discussions 7(3):4127-4152. Article.
