Antarctica, along with its little brother the North Pole have become poster children for globe-warming, and with good reason. If the ice from this to polar regions melted it would have dramatic consequences for our world and society.
So how do we find out if the ice is melting? Well, one thing to do would find out how thick the ice is and then monitor it for change. Satellites are a good choice for this kind of monitoring. Not only do they pass overhead on a regular base but their extremely stable orbit means that the can make consistent and accurate measurements which can then be used in comparisons over time. Another good thing about satellites is they can cover large geographic areas and they can be equipped with sensors that are cable of "seeing" through the ice.
Seeing through the ice is a good thing if you want to find out how deep the ice is. If you could look through the ice and calculate the elevation of the underlying bedrock you could then remove that elevation from the surface elevation ( remember that about 98% of Antarctica is covered by ice) and thus calculate the thickness of the ice. Knowing the thickness of the ice year for year makes it possible to monitor change over time.
This is what Antarctica looks like without ice
This is what Antarctica looks like with ice
images are sourced from - https://earthobservatory.nasa.gov