 using lots and lots of different methods, both area and volume. Is there any going back? The longer we leave it, the harder it's going to become. The problem with ice fields like this is they are sustained by their own ice volume. They're not the small mountain glaciers that we have in the European Alps that can just shrink back, and then if it stops warming, they can stabilise. As the climate warms, this ice field will continue to lower, and as it lowers, it lowers into warmer air.