This paper (Sami Prehistory Revisited by John Weinstock, University of Texas) states, "the maps (above) show the ice sheet at 10,000 BP and 9,300-9,200 BP (Eronen et al. 2001: 19). They illustrate how rapidly the ice was shrinking and the avenues by which humans could reach Fennoscandia."
By ca. 13,000 BP long stretches of the Norwegian coast were ice-free but, as Hein Bjartmann Bjerck points out, there was “no certain evidence of human settlement in this rich arctic biotope” until near the end of the Younger Dryas (1,300 year cold snap) about 10,000 BP (2008: 65). The earliest evidence of human activity in Scandinavia is during the Early Mesolithic chronozone from 10,020-8,900 BP (9,500-8,000 cal BC); Bjerck lists 37 key sites in Norway (Ibid. 75-78). There were three coastal techno-complexes: the Fosna along the coast of southern Norway, the Hensbacka in southwest Sweden near Bohuslän and the Komsa in northern Norway, all with a forerunner in the late Paleolithic Ahrensburg culture further south (Ibid. 74). The Middle Mesolithic chronozone 8,900-7,690 BP and the Late Mesolithic chronozone 7,690-5,230 BP follow, the latter period witnessing an increase in rock art.