Do any of you know how sea level rise will affect marine glaciers? In my head rising seas will affect melting and also make marine glaciers more unstable and speed up the collapse of the glaciers, but there is a big chance that I am wrong.
It's not a simple question, let me try to answer:
* Marine glaciers (the big ones) can be more than a kilometer deep below the sea surface, and hundreds of meters above the sea surface. So a few meters of sea level rise should not change the picture much.
* On the other hand, if the glacier is finely balanced on its grounding line, a few meters of sea level rise could cause its front part to float, causing it to accelerate somewhat.
* However, a much stronger effect would be caused by the gravitational pull of the ice sheet. Should Greenland lose half its mass to melting, thereby causing several meters of SLR, the sea surface height around Greenland will lose tens of meters, as the ice sheet exerts a much smaller pull on the water around it. So remaining marine glaciers in Greenland will actually experience the opposite of SLR.
* In such a case of only Greenland melting, local SLR around Antarctica will actually be higher than the global average, as Antarctica is on the opoosite side of the globe from Greenland.
I hope this helps.