to say that the ice caps are melting gives the wrong impression....

to say that the ice caps are melting gives the wrong impression. It's not that the surface of the ice is melting, the temperature remains far to way below freezing point for that to happen.
What happens is that the edges are breaking off. The edges have always broken off because ever since ice has been forming there, the increased weight as it builds up causes it to move outwards towards a point of lower pressure, as well as increasinging temperatures due to the shape of the planet. Eventually it passes a balance point where the lower pressure means the ice is unable to support itself.
If the ice at the edges of ice shelf were actually shedding water then it would obvious that it was melting, but the ice being shed is still well below freezing point, so it must be an ongoing force from behind it that is causing it to move. Given that most of the base of the WAIS is below sea level, gravity is not a factor.
I think that a decrease of ice being shed would be the indicator of less ice being formed due to rising temperatures.