I WONDER - What Is An Iceberg?

Icebergs are large ice pieces that break off from glaciers and ice shelves. They form when glaciers move towards the ocean or when ice breaks away from ice shelves. Once separated, they float freely in the ocean. Icebergs vary in size from small growlers to massive ice islands, some larger than cities.

How do glaciers contribute to the formation of icebergs?

What is the significance of icebergs in the ocean ecosystem?