Selyuzhenok, Valeria, Climate Variability and Change in High Northern Latitudes, Nansen International Environmental and Remote Sensing Centre, St Petersburg, Russia; Sea Ice Physics, Alfred Wegener Institute Helmoholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany, and Department of Cartography & Geoinformatics of the Institute of Earth Sciences, St Petersburg State University, St Petersburg, Russia, Russian Federation