David Attenborough's new documentary argues that our oceans have been underexplored and undervalued. Could protecting our seas not only help biodiversity, but fix the climate too?

Keith Scholey, one of the directors of "Ocean With David Attenborough", tells The Climate Question how the world’s seas are at a critical turning point. Many countries have pledged to protect a third of the world’s oceans, and the film’s creators hope it will push global leaders to deliver on their promise at this year's UN conference on oceans.

The documentary also includes some of the most detailed footage ever captured of bottom trawling, a widespread fishing method that damages the seabed.

In this episode we ask why we know so little about the ocean? And why the largest part of our planet been under-protected for so long?

Presenters: Graihagh Jackson and Jordan Dunbar Producer: Beth Timmins Sound Engineers: Ben Andrews, Mike Regaard and Tom Brignell Editor: Simon Watts

Got a question? Email us: theclimatequestion@bbc.com