Subglacial volcano sheds light on future of West Antarctic Ice Sheet
British researchers have found evidence of a volcanic eruption under the West Antarctic Ice Sheet. The subglacial volcano erupted 2000 years ago and remains active, the scientists from the British Antarctic Survey (BAS) report in the journal Nature Geoscience. 'The discovery of a 'subglacial' volcanic eruption from beneath the Antarctic ice sheet is unique in itself,' says Hugh Corr of the BAS, lead-author of the study. 'But our techniques also allow us to put a date on the eruption, determine how powerful it was and map out the area where ash fell. We believe this was the biggest eruption in Antarctica during the last 10,000 years. It blew a substantial hole in the ice sheet, and generated a plume of ash and gas that rose around 12 km into the air.' The researchers were able to discover this using airborne ice-sounding radar. This method revealed a layer of ash produced by the volcano that extends across an area larger than Wales. The find not only sheds light on this past eruption, however; it will also help determine the future of the West Antarctic Ice Sheet and refine predictions of future sea-level rise. 'This eruption occurred close to Pine Island Glacier on the West Antarctic Ice Sheet,' co-author Professor David Vaughan explains. 'The flow of this glacier towards the coast has speeded up in recent decades and it may be possible that heat from the volcano has caused some of that acceleration. However, it cannot explain the more widespread thinning of West Antarctic glaciers that together are contributing nearly 0.2mm per year to sea-level rise. This wider change most probably has its origin in warming ocean waters.' The volcano is located beneath the West Antarctic Ice Sheet in the Hudson Mountains. Volcanoes are an important component of the Antarctic region. They formed in diverse tectonic settings, mainly as a result of mantle plumes, an upwelling of hot rock within the Earth's mantle, acting on the stationary Antarctic plate.
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Antarctica, United Kingdom