Asked by Morag
Wow, this is an interesting question! You can learn all about subglacial volcanoes here. The West Antarctic Ice Sheet has many subglacial lakes beneath it; geothermal heating is thought to contribute to the melting of the base of the West Antarctic Ice Sheet. However, the extent of this, and the rate, is very poorly known and currently not included in glaciological numerical models. Actual volcanoes may, during eruptions, melt quite large portions of the ice sheet around them. In Iceland, volcanic eruptions beneath the ice sheet regularly cause catastrophic floods, called jokulhlaups. Subglacial volcanoes are therefore probably contributing at least a little to Antarctic ice sheet melt; the extent to which this is happening is probably reasonably stable over longer timescales.