I have noted, with great amusement, an argument circulating that purports to disprove sea level rise as a result of melting ice caps and glaciers. The argument posits a glass of water with ice cubes floating in it as an analogy for the world’s oceans and points out that as ice melts in a glass, the water level actually lowers. This is a well known phenomenon to scientists since ice has a very different physical behavior than most solids. It expands as temperature lowers. Ice does in fact take up more volume than liquid water. This is why it floats.
The flaw in the ice in the glass argument is that it is only partly true. The Arctic ice cap is floating on water and is already part of the world’s ocean systems. The Antarctic ice cap, which is much larger, is not floating. It rests on the large land mass of the continent Antarctica. The world’s glaciers also rest on land. In terms of the ice in the glass argument, both the glaciers and the Antarctic ice cap are not in the glass. They are outside the system.
A better model for Antarctica would be to melt ice in another container and then pour it into the glass. This is a more accurate analogy to the world wide reality of sea level rise. As the Antarctic ice cap and glaciers melt the resulting water leaves the land and flows into the oceans, increasing the overall volume of the water.
Of course there are those who argue that the ice isn’t melting at all, but that is an entirely different question.