system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5: Why is glacier preservation so important? What would happen if they were to be completely melted across the globe?
gpt
Glacier melting is seen as a significant indicator of global temperature. They are long standing, relatively stable structures. If they start disappearing, it means conditions have changed that were constant for a very long time.

Furthermore, a lot of them are on land, which means if they melt they add their water to the ocean, which can potentially raise sea level.

So in and of themselves, they represent a danger, but also they represent a signal of a greater danger, global warming.