Oh no, I didn't think you were, it's just that viewing water vapor as a GHG in a certain context can lend itself to that obnoxious argument. We do exhale CO2 every time we breathe, but it's being cycled, as opposed to releasing what's been trapped underground for a long time in a short period. In this case, the current carbon sinks just can't handle it, and the atmospheric concentration increase. As for what dictates the amount of glacial cover we have, so far as I know, it's just average temperature. There's always a seasonal flux, some of the glacier melts away in summer, and is rebuilt in winter, but recently, the poles have really heated up, about twice the average rate iirc, the sea level has, and probably will increase as land locked water melts and runs off into it. Since most of this is freshwater, the
oceanic conveyor's range is decreasing. While it used to dump more heat at higher latitudes, it's slowing/shrinking and we have more heat concentrated near the equator, but higher latitudes aren't getting as much overall. So we'll see colder colds and warmer warms iirc, different forms of climate change depending on where we live.