If I have interpreted the story correctly, it sounds as if they are
saying that reefs are extending into areas which were previously too
cold to support a coral reef.
This is something that I have never really thought about. Most
environmentalists warn about the loss of coral reefs from global
warming due to the overheating of waters. If this story is true, then
it suggests that coral reefs will simply "migrate" or spread to areas
which historically have been too cold to support coral reefs.
Interesting.....