This is an example where you and gbw are both right. It is clear that ice has receded in some spots and grown in others. You are certainly correct, melting ice does not lie, and disappearing ice cover indicates warming in that area of the Earth. It does not tell us what is causing the warming, and it does not tell us what is going on elsewhere on the Earth. The concern is global warming not regional ice cap warming per se, and as we all know the Earth does not warm or cool uniformly. It is difficult to learn what the overall trend is, if any. Our most reliable data, though it could be subject to systematic error, of course, is coming from remote sensing satellites. That data is telling us, within reasonable confidence limits, that there has been no measurable net warming or cooling for nearly two decades.