The top United Nations court has taken up the largest case in its history, hearing the plight of small island nations facing rising sea levels.

In the decade up to 2023, sea levels have risen by a global average of around 4.3 centimeters (1.7 inches), with parts of the Pacific rising higher still. The world has also warmed 1.3 degrees Celsius (2.3 Fahrenheit) since preindustrial times because of the burning of fossil fuels.

The hearings come after years of lobbying by island nations who fear they could simply disappear under rising sea waters,