The Telegraph reports that previously undetected streams of meltwater have been observed beneath the Antarctic ice sheet. "The streams of water, some of which are 250m in height and stretch for hundreds of kilometres, could be destabilising parts of the Antarctic ice shelf immediately around them and speeding up melting, researchers said. However, they added that it remains unclear how the localised effects of the channels will impact on the future of the floating ice sheet as a whole. The British researchers used satellite images and radar data to measure variations in the height of the Filchner-Ronne Ice Shelf in West Antarctica, which reveal how thick the ice is." The paper itself is paywalled, but the abstract is available online.