A new interpretation of the date of the ‘Little Ice Age’ glacier maximum at Svartisen and Okstindan,northern Norway

Abstract

New results concerning the dating of ‘Little Ice Age’ glacier variations at Svartisen and Okstindan, northern Norway, are presented. Measurements of lichens of the Rhizocarpon subgenus on gravestones are used to construct several local sets of lichenometric dating curves. These are partly ‘adjusted’ in relation to well-established lichenometric dating curves from southern Norway. The ‘Little Ice Age’ maximum at Svartisen and Okstindan is thereby dated to the mid-eighteenth century (i.e., in agreement with southern Norway). Pre viously suggested earlier ‘Little Ice Age’ advances are demonstrated to have resulted from an underestimation of the growth rates of the Rhizocarpon subgenus. Synchroneity of ‘Little Ice Age’ maxima in southern Norway and at Svartisen and Okstindan suggest that a north–south migration of latitudinal depressional tracks can be excluded as the main forcing factor. As an alternative, an increased SE–NW trend of moist air‘ ow in winter parallel to the coast of Norway is suggested as the main forcing factor with recent glacier dynamics in response to recent climatic ‘ uctuations supporting this hypothesis.