Crevasse formation and its relationship to glacier calving

Abstract

The work reported here formed part of a NERC-funded PhD project undertaken by R.H. Mottram and supervised by D.I. Benn (University of St Andrews), on the dynamics and calving retreat of Breiðamerkurjökull, an outlet of the Vatnajökull ice cap in South East Iceland (Fig. 1). The overall aims of the project were to assess the role of glacier velocity gradients on crevasse formation, calving, and thinning of the glacier, and to test a new model of calving glacier dynamics (Benn et al., 2007a, b). Fieldwork involving DGPS equipment had two main objectives: 1. To measure the horizontal and vertical displacement of stakes on the glacier surface, to allow calculation of ice velocity and three-dimensional strain rates. 2. To determine recent retreat rates by mapping the position of the glacier terminus.