eCite Digital Repository

Standing waves during ice breakup in a polar lake

Citation

Kirillin, G and Engelhardt, C and Forrest, A and Graves, K and Laval, B and Lepparanta, M and Rizk, W, Standing waves during ice breakup in a polar lake, Proceedings of the 22nd IAHR International Symposium on ICE, 11-15 August 2014, Singapore, pp. 467-470. ISBN 978-981-09-0750-1 (2014) [Refereed Conference Paper]

Copyright Statement

Copyright 2014 IAHR-ICE Organisers.

Official URL: http://www.iahr-ice2014.org/

Abstract

Strong wind events play a crucial role in breaking the seasonal ice sheet in lakes and marginal seas. Still, the mechanism of ice break-up is poorly investigated. We demonstrate that, apart from the obvious effect of horizontal drift, wind produces basin-scale standing waves (seiches) under ice, which, in turn, may essentially contribute to breaking the ice sheet and accelerate ice melting. An extensive dataset on lake physical properties during the ice breakup has been aquired in spring 2013 in polar Lake Kilpisjarvi, Finland. The high-resolution records of pressure, current velocities and water temperature revealed continuous oscillatory motions with periods of 10 to 25 min. The spectral energy peaks resided on frequencies corresponding to the first three eigenfrequencies of the lake indicating the oscillations are produced by the seiche movements at t he lake surface. In agreement with previous studies, seiches persis1ed under ice cover. During the period preceding the breakup, amplitudes of the lake surface oscilations under ice did not exceeded lmm. The ice breakup was associated with a strong wind event and a 10 times increase of seiche amplitudes under ice. We suggest that vertical motions of the soft ice sheet significantly accelerated its melting, so that at the lake surface covered by ice to 80 per cent, the ice completely melted within 10-15 hours.

Item Details

Item Type:Refereed Conference Paper
Keywords:standing waves, ice-breakup, ice covered lakes, polar lakes
Research Division:Earth Sciences
Research Group:Geophysics
Research Field:Geophysical Fluid Dynamics
Objective Division:Environment
Objective Group:Other Environment
Objective Field:Environment not elsewhere classified
Author:Forrest, A (Dr Alexander Forrest)
ID Code:94130
Year Published:2014
Deposited By:NC Maritime Engineering and Hydrodynamics
Deposited On:2014-08-30
Last Modified:2015-05-20
Downloads:0

Repository Staff Only: item control page