Thermal expansion

At the same time, seawater expands as it warms: this is thermal expansion. Both processes contribute to rising sea levels.

Thermal expansion: seawater expands as it warms, occupying more space.

First, ocean water expands as it warms. This thermal expansion increases the volume of the oceans. Second, melting glaciers and ice sheets on land add water to the oceans.

Seawater expands as it warms: this is thermal expansion. Melting glaciers and ice sheets on land also add water to the oceans. Melting floating sea ice is not the same as adding previously land-based ice to the sea.