Reality check for reviving dead and dying coral reefs

An expert says people have unrealistic perceptions about the cost and ways of saving coral reefs. (Darren England/AAP PHOTOS)

Restoring tropical coral reefs already lost to rising temperatures could run into the trillions of dollars, prompting calls for climate action and strategic conservation.

Not only are restoration projects prohibitively expensive at the massive scale that's needed, roughly one-third are not successful.