system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does ice in a freezer get smaller over time?

I saved some snowballs from the first snowfall in our new house in Virginia. Over time, the snowballs have gotten smaller and smaller. Where is the water going?
gpt
It is evaporating, or, to give it its right name, sublimating. Just like liquid water evaporates into the air, ice does too. Either the water vapor in the freezer escapes when you open the door, or it ends up creating frost on the inside of the freezer.