* Glaciers are heavy. They exert tremendous pressure on the land beneath them. Think of a giant ice cube sitting on a squishy pillow—it will push the pillow down.

* Melting releases pressure. As glaciers melt, this pressure is relieved, allowing the land to slowly "rebound" upwards. This is called isostatic rebound.

* The land doesn't always sink. While the land under a glacier is pushed down, the land around it is actually pushed up slightly. This is because the weight of the glacier causes the Earth's mantle (the layer beneath the crust) to flow outwards.

So, here's a breakdown:

* Directly under the glacier: As the glacier melts, the land rises up as it rebounds.

* Surrounding areas: As the glacier melts and the mantle flow subsides, the land sinks slightly.

Important Note: Isostatic rebound is a very slow process, happening over centuries or even millennia. It doesn't happen overnight!

In summary:

* Glaciers do exert pressure on the land, causing it to sink.

* When glaciers melt, this pressure is relieved, causing the land to rise.

* This is called isostatic rebound and happens over long periods.