Sea Level Rise

Sea levels are rising because warming water expands and ice on land melts into the ocean. Rising seas can flood coastal areas and force people to move.

Global sea levels have risen by about 20 centimetres since 1900.

When water gets warmer, it expands and takes up more space. Also, ice on land, such as glaciers and ice sheets, melts and adds water to the oceans. Together these changes make the seas rise over time.

Protecting coasts with walls, planting mangroves and reducing greenhouse gases are ways to deal with this problem.