On the Deterioration of a Grounded Iceberg

• Published in: Journal of Glaciology
• Main Author: Venkatesh, S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1986
• Subjects: Earth-Surface Processes; Canada; Journal of Glaciology; Newfoundland
• Online Access: http://dx.doi.org/10.1017/s0022143000015471; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000015471

Abstract This paper examines the deterioration of an iceberg grounded outside St. John’s Harbour, Newfoundland, Canada, in terms of its initial velocity prior to grounding. Theoretical expressions for the lifting of the iceberg and hence its buoyancy loss during grounding are derived as a function of initial iceberg velocity and ocean-bottom slope. Wave erosion and calving are two of the most significant mechanisms for iceberg deterioration. With wave erosion occurring on the seaward side of the grounded iceberg, model simulations are compared with observational data from a field study conducted on the grounded iceberg between 10 and 17 June 1983. Model–simulated time of re-flotation of the iceberg agrees with observations, for initial iceberg velocity of 0.3–0.5 m/s. Model simulations of the deterioration of the iceberg beyond the point of re-flotation are also compared with observations. Allowing for a 10% error in the observed above-water volume of the iceberg on 10 June, the model-simulated mass losses are in good agreement with observations. Best results are obtained for the model initialized with data observed on 14 June 1983, the first day for which detailed observational data are available following re-flotation of the iceberg.