Sirkku Manninen,^* Satu Huttunen,^** Hans Tømmervik,^*** Lars R. Hole,^**** Sverre Solberg<sup>*****


*</sup>Sirkku Manninen is a senior lecturer of environmental biology at the University of Helsinki. She holds a PhD in plant ecology from the University of Oulu. She has been working on the critical levels of air pollutants since the early 1990s, especially the environmental effects of ozone. Recently, her research has focused on climate change and urban ecology issues with a special emphasis on the structure and function of natural ecosystems. Her address: Department of Biological and Environmental Sciences, P.O. Box 56, FI-00014, University of Helsinki, Finland. sirkku.manninen@helsinki.fi
^**Satu Huttunen acts as professor of functional plant ecology and environmental ecology at the University of Oulu. She is a specialist in plant responses to air pollutants. She has worked with diagnostic plant pathology, element analyses, and conifers since the early 1970s. She was one of the originators of the UN/ECE LRTAP Convention Working Group on Effects in November 1978, when the air quality criteria for forests were drawn up for the first time. Her address: Botany Division, Department of Biology, P.O. Box 3000, FI-90014 University of Oulu, Finland. satu.huttunen@oulu.fi
^***Lars R. Hole is a senior research scientist at the Norwegian Institute for Air Research. He holds a PhD in meteorology from the University Center on Svalbard and the University in Bergen. His professional interest is the atmospheric transport and deposition of inorganic pollutants, in particular sulfur, nitrogen, and ozone, with an emphasis on field experiments and micrometeorology. His address: Norwegian Institute for Air Research, Tromsø office, Polar Environmental Center, N-9296 Tromsø, Norway. lrh@nilu.no
^****Hans Tømmervik, Dr, has worked on the application of remote sensing methods as well as on conventional survey methods in the mapping and monitoring of boreal and arctic–alpine vegetation with a focus on impact variables such as air pollution, climate, logging, herbivores, and reindeer husbandry. He was a member of the Terrestrial Expert Group under the Joint Norwegian–Russian Commission on Environmental Co-operation in 1989–1996 that worked on air pollution problems that affect the vegetation on the Kola Peninsula (Russia) and in Norway. His address: Norwegian Institute for Nature Research (NINA), Polar Environmental Center, N-9296 Tromsø, Norway. hans.tommervik@nina.no
^*****Sverre Solberg has a MSc in meteorology (atmospheric chemistry) from the Department of Geophysics, University of Oslo, and he is a senior scientist at Norwegian Institute for Air Research. His main role at The Department for Regional and Global Pollution Issues concerns boundary layer ozone, volatile organic compounds, and oxidant formation in the troposphere. The work involves application and development of numerical models, statistical tools, and analyses of measurement data. National and European issues are the main focus of the work. His address: Norwegian Institute for Air Research (NILU), P.O. Box 100, N-2027 Kjeller, Norway. sso@nilu.no