Margareta Johansson,^* Jonas Åkerman,^** Frida Keuper,^*** Torben R. Christensen,^**** Hugues Lantuit,^***** Terry V. Callaghan<sup>******


*</sup>Margareta Johansson () is a researcher at the Department of Earth and Ecosystem Sciences, Lund University and at the Royal Swedish Academy of Sciences, Stockholm, Sweden. She specializes in permafrost dynamics in relation to climate change and its impact on ecosystems. Address: Division of Physical Geography and Ecosystem Analyses, Department of Earth and Ecosystem Sciences, Lund University, Sölvegatan 12, 223 62 Lund, Sweden. Address: Royal Swedish Academy of Sciences, PO Box 50005, 104 05 Stockholm, Sweden. e-mail: margareta.johansson@nateko.lu.se
^**Jonas Åkerman is Associate Professor at the Department of Earth and Ecosystem Sciences, Lund University. He specializes in geomorphology and periglacial processes in relation to climate and its variations in Arctic and Alpine environments. Address: Division of Physical Geography and Ecosystem Analyses, Department of Earth and Ecosystem Sciences, Lund University, Sölvegatan 12, 223 62 Lund, Sweden. e-mail: jonas.akerman@nateko.lu.se
^***Frida Keuper PhD student at the Department of Systems Ecology, VU University Amsterdam, The Netherlands. She specializes in subarctic vegetation responses to changing environmental conditions. Address: Department of Systems Ecology, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands. e-mail: frida.keuper@ecology.falw.vu.nl
^****Torben R. Christensen is Professor at the Department of Earth and Ecosystem Sciences, Lund University, Sweden. He specializes in how vegetation and ecosystem processes respond and provide feedback effects on climate under changing environmental conditions. Address: Division of Physical Geography and Ecosystem Analyses, Department of Earth and Ecosystem Sciences, Lund University, Sölvegatan 12, 223 62 Lund, Sweden. e-mail: torben.christensen@nateko.lu.se
^*****Hugues Lantuit is Research Scientist at the Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany. He specializes in the reaction of ice-rich permafrost environments to changing environmental conditions, especially in the western Canadian Arctic. Address: AWI Potsdam, Periglacial Section, Telegrafenberg A43, 14473 Potsdam, Germany. e-mail: Hugues.Lantuit@awi.de
^******Terry V. Callaghan is a Distinguished Professor at the Royal Swedish Academy of Sciences and Professor of Arctic Ecology at Universities of Sheffield, UK and Lund, Sweden. He specializes in arctic ecology and climate and UV-B radiation impacts on arctic ecosystems. Address: Royal Swedish Academy of Sciences, PO Box 50005, 104 05 Stockholm, Sweden. Address: Department of Plant and Animal Sciences, Sheffield Centre for Arctic Ecology, University of Sheffield, Sheffield S10 5BR, UK. e-mail: terry_callaghan@btinternet.com