Snowfall will matter less and less.
The Antarctic Mosaic shows a lot of very subtle changes in the slope of the terrain that you cannot see from the ground. These subtle variations are important because they tell us the direction the ice is flowing now and they indicate where it has gone in the past. The surface roughness also tells us about the bed underneath the ice and whether the ice is sliding over the bed or frozen to it.
Snowfall will matter less and less. We know that warmer climates eventually lead to less ice.
There is a big temperature contrast between the warm ocean water and the cold ice, and melting occurs at a very rapid rate. The melting reduces the friction that holds these glaciers back, allowing them to accelerate.