Calving front dynamics : External forces that lead to specific sized calving events

• Main Author: Wainwright, Daniel
• Format: Bachelor Thesis
• Language: English
• Published: Uppsala universitet, Institutionen för geovetenskaper 2014
• Subjects: Greenland; calving; climate; photography; glacier; tidewater; Physical Geography; Naturgeografi; Tidewater
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-237686

Currently there is no extended study that explicitly focuses on themagnitude, frequency and timing of glacial calving resulting from externalforces. Past studies have identified the size and timing of calving events butthe links between them and the external factors that cause them are stillmissing. Here I present a method to identify the size, time and frequency ofcalving events on the Rink Glacier in Greenland. Using time lapse imagesspaced 30 minutes apart of the calving front, coupled with weather and tidedata, I plan on identifying the main driving force for calving. Results showthat atmospheric pressure and temperature have no positive correlation withcalving magnitude or size. Tidal influences and sea surface temperatureappear to have the strongest influence on the frequency of calving. As seasurface temperatures rapidly decrease though the study period, calvingfrequency also reduces. Strong calving correlations for the entire studyperiod were difficult to identify for tidal influences, as images could only betaken during the sunlit periods of the day. As this study was conductedduring autumn when atmospheric temperatures remained below 0°C, theavailability of melt water for crevasse creation and basal lubrication was notpresent. Therefore it is suggested that future studies on glacial stabilityshould use external forces to measure ice loss over the entire calving season.