The Larsen C ice shelf is the northernmost of the major shelves in Antarctica, a little smaller in area than Scotland—and part of it is in danger of breaking off. Currently, there is a 130km-long crack in it that has been growing rapidly in the last few years. It grew 22km since March of 2016 and could result in a chunk about the size of Prince Edward Island breaking away.
This in itself won’t directly contribute to the rise of sea levels, but it could be a signifier of a larger problem. Ice shelves rest on top of the ocean. They’re already floating, so if this piece breaks off, it won’t displace any more water. However, such an event could quickly lead to more ice from that shelf breaking away, as happened with other shelves in 1995 and 2002.
The problem then is that ice shelves hold back ice that is actually on the land of Antarctica, so when the shelves break away, that ice pushes forward and eventually it can reach the ocean. If that ice gets into the water, it will raise water levels.
Ice shelves break sometimes, but this would be the third significant breakage in 20 years, and this ice has probably been in that spot for almost 12,000 years. The previous breakages led to the loss of their respective shelves, and that seems likely in this case as well. It seems pretty obvious that the recent breakages have something to do with climate change.
For now, we simply have to watch the ice and see what happens, as predicting these types of events is a lot like predicting an earthquake. You can know that one is likely coming, but you can’t pin down when it will happen. It could be next month or several years away.
The growing crack in the Larsen C ice shelf is another sign that we need to reduce our carbon emissions and begin relying on green power generation technologies such as solar, so that we can do something to slow or stop global climate change.