Low-frequency bursts of horizontally polarized waves in the Arctic sea-ice cover

© V.Hilaire/Fonds Tara

Tara Arctic

Authors: Marsan, David; Weiss, Jérome; Métaxian, Jean-Philippe; Grangeon, Jacques; Roux, Pierre-François; Haapala, Jari

Source: Journal of Glaciology, Volume 57, Number 202, April 2011, pp. 231-237(7)

Publisher: International Glaciological Society

couv publi arctic

Upload PDF

Abstract

We report the detection of bursts of low-frequency waves, typically f = 0.025 Hz, on horizontal channels of broadband seismometers deployed on the Arctic sea-ice cover during the DAMOCLES (Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies) experiment in spring 2007. These bursts have amplitudes well above the ambient ice swell and a lower frequency content. Their typical duration is of the order of minutes. They occur at irregular times, with periods of relative quietness alternating with periods of strong activity. A significant correlation between the rate of burst occurrences and the ice-cover deformation at the ~400 km scale centered on the seismic network suggests that these bursts are caused by remote, episodic deformation involving shearing across regional-scale leads. This observation opens the possibility of complementing satellite measurements of ice-cover deformation, by providing a much more precise temporal sampling, hence a better characterization of the processes involved during these deformation events.