Warm summers shown to slow down glaciers
Hotter summers may not be such a disaster for the Greenland ice sheet after all, if the latest research is anything to go by. Scientists have found that Greenland glaciers flow slower in warmer summers than they do during cooler ones. Although this seems counter-intuitive, the researchers explain that during cooler summers, a small amount of melted water from glaciers' surfaces seeps down to their bases, lubricating them so they move more easily.
But during warm summers, much more melted water makes its way underneath glaciers. This water bores out wider channels and so drains away faster, leading to less lubrication.
This is exactly what happens in mountain glaciers, 'where melt-induced acceleration of flow ceases during years of high melting once subglacial drainage becomes efficient,' write the authors in their report, published in Nature today.
'Our findings are certainly at odds with what people might expect,' says Professor Andrew Shepherd from the University of Leeds, co-author of the study.
Article continues: http://planetearth.nerc.ac.uk/news/story.aspx?id=910