The CO₂ emitting mineral springs of Iceland have been surveyed and assessed for their use in understanding the potential effects of elevated atmospheric CO₂ on northern ecosystems. One spring near Olafsvik is described in detail here. This CO₂ spring emits CO₂ in such a way that the surrounding vegetation is exposed to mean CO₂ concentrations which are consistent with those predicted for the next century. Results from carbon isotope analyses show that Nardus stricta plants growing near this CO₂ spring are exposed to mean CO₂ concentrations of approximately 880, 650 and 430 ppm, depending on their location relative to the CO₂ vent. Maps and tables are provided to show how the concentration of CO₂ measured in the vegetation varies over time on calm and windy days. A list of the species growing around the Olafsvik CO₂ spring is included and the research potential of CO₂ springs is discussed at length. The use of natural CO₂ springs as surrogates for elevated CO₂ experiments appears highly promising.
