A new paper finds that there is already enough genetic variety spread across the Great Barrier Reef to adapt to the imagined “unprecedented” warming coming in the next two centuries.
We don’t need to rely on random mutations or consider fantasy solutions of man-made oceanic sunscreens, mass sunshades, or giant reef fans. Corals already have a major immigration program running pretty effectively to juggle 200 million years of genetic material and then spread the successes far and wide. Meddling humans can help things (maybe) by moving a few bits of coral around. That’s it. Cancel the scare please.
Skeptics have been saying this for years — who needs a computer model to predict that the Barrier Reef will adapt? How bad could global warming be? The global oceans span a 32C range and corals prefer the hottest five degrees of that. Indeed, there is a five degree temperature range from one end of the Great Barrier Reef to the other, and corals are clearly, obviously pretty happy about. Meanwhile, the atmosphere is warming at a mere tenth of a degree per decade. Then there is the well known phenomenon that corals spawn in vast clouds that are so big they can be seen from space and there is a whole new generation of corals every five years. You don’t need to be Nostradamus to figure out that survivors from some parts of the reef will reseed other parts, as they have done for eons. Half of the coral genera around today have been around since the Oligocene (23-34 million years ago).
Corals also adapt to heatwaves by chucking out the algal symbionts that don’t thrive in higher temperatures. So on top of their own genetic adaptability, they can “gear up” in different ways too. In the unlikely event that IPCC climate models are right for the first time in history, corals will cope.
Climate change just shifts this large range slightly south. So what?
If the water gets warmer to the South, Great Barrier Reef corals will probably spread further.