@Julie Brooks-Girskiene Treebeard It is partially magma, but there is also an issue, in Greenland and also in Antarctica, of warm (or warmer than before) ocean water seeping underneath the ice and that is contributing to the melting as well.
As well as the melting, this warmer water causes the line where the ice sheets are stuck to the bedrock to move further inland which makes the ice shelves more fragile and to break up more easily.
