Understanding the inner causes of glacial calving and surging could provide insight into how ice will respond to a warming world. These topics were highlighted at the June IRIS workshop, which held its very first session on glacial seismology, co-organized by Wiens; there Nettles, Anandakrishnan and many others presented their findings. The field is growing rapidly, Wiens remarks. Seismologists get a new place to apply their skills, glaciologists get a new tool to apply to the ice and everyone learns more about changing ice.

Note: This story was originally printed with the title, "The New Ice Doctors".

2 Comments

1. 1. doug l 06:48 AM 9/30/08

   Interesting article but way too superficial. For instance, regarding the Columbia Glacier in Alaska. The article relates how the glacier is both moving forward but also retreating but fails to mention that the dynamics of a glacier like the Columbia, moving through its deeply carved valley/fjord into salt water means that it's behaviour is typical of that kind of Glacier and instead implies something mysterious and related to climate change.

   Reply | Report Abuse | Link to this

2. 2. Squatchmichael 08:39 PM 3/30/09

   I am glad to see SA introducing seismology to the public as a tool for glaciology. I agree with the prior comment, however in that the article is somewhat superficial. As a glacial-seismologist, (sicemologist?) I see it's most promising application in basal sliding studies in the presence of meltwater. Ekstrom's paper illustrated that long-period seismic events are coincident with melt-season surging of Greenland's ice sheets. A relevant question is "how is melt water volume mapped into ice sheet sliding?" No doubt the answer is case specific and depends on a variety of physical mechanisms for delivering the water to the bed. Recently (2008) Ian Joughin and Sara Das observed that drainage of supraglacial lakes in Greenland can inject a lakes-worth of water to the bed in under 2 hours, but that the perturbation to the ice-speed is localized spatially and temporally. It seems that the sub-glacial drainage system adapts quickly to that volume of water. At calving faces, like on Columbia, 90% of the ice face is exposed to water and the physics is different: the ice is floating, dilating and compressing, and acts as a thermal sink for the heat contained in the water. Point being, there is a lot going on. Some details of the physics should be explained in a Scientific American article. Otherwise it sounds like about as technical as a History Channel program (I love the History Channel, don't get me wrong).

   Reply | Report Abuse | Link to this