1. Institute of Botany; University of Basel; Schönbeinstrasse 6 Basel CH-4056 Switzerland
2. New Zealand Forest Research Institute (SCION); Te Papa Tipu Innovation Park; 49 Sala Street Rotorua 3046 New Zealand
3. Institute for Applied Ecology New Zealand; School of Applied Sciences; Auckland University of Technology; 31-33 Symonds Street Auckland 1142 New Zealand
4. Physics Institute and Oeschger Centre for Climate Change Research, Climate and Environmental Physics; University of Bern; Sidlerstrasse 5 Bern CH-3012 Switzerland
5. Laboratory for Atmospheric Chemistry; Paul Scherrer Institute; Villigen PSI CH-5323 Switzerland
6. Swiss Federal Institute for Forest, Snow and Landscape Research (WSL); Zürcherstr. 111 Birmensdorf CH-8903 Switzerland