How will a country such as New Zealand, with a number of coastal cities, cope with rising sea levels from a heating world?

An interactive map built to promote Before The Flood, a climate change documentary by actor Leonardo di Caprio and National Geographic, has made that question accessible to the public.

It shows predicted sea level rise based on temperature increases between 0.5degC and 4degC, ranging between an increase of 0.7m and 8.9m.

"Every fraction of a degree of global warming sets in motion sea level rise that will profoundly threaten coastal cities across the world," said Benjamin Strauss, vice president for sea level and climate impacts at Climate Central.

A number of countries have committed to a limit of 2degC rise as part of the Paris Agreement.

But according to the data displayed by National Geographic, the resulting rise in sea level would still endanger a number of our coastal cities, including parts of Christchurch, Blenheim, Dunedin and Napier.