A new study from James Cook University shows we have only a small window of opportunity to reduce the impacts carbon emissions have on the world’s reefs.
The research looked at how the reefs could possibly cope with warming and acidification under three different climate change carbon dioxide scenarios: low, medium and worst-case.
Researchers found that even under the low-impact scenario, reefs would suffer severely reduced growth or accretion rates. In the medium-impact projections, the reefs may keep pace with the rising sea levels, but only for a little while. The worst-case or high-impact scenario is as bad as it sounds.
“The threat posed to coral reefs by climate change is already very apparent, based on recurrent episodes of mass coral bleaching,” said co-author Professor Morgan Pratchett from the ARC Centre of Excellence for Coral Reef Studies at James Cook University. “Saving coral reefs requires immediate and drastic reductions in global carbon emissions.”
Pratchett’s colleague Dr Scott Smithers states that by the year 2100, reefs worldwide could face crippling scenarios under the intermediate impact projections.
“All reefs around the world will be eroding by the end of the century under the intermediate scenario,” Dr Smithers said. “This will obviously have serious implications for reefs, reef islands, as well as the people and other organisms depending upon coral reefs.”
A report from the United Nations Environment Program recently estimated that most of the world’s reefs will suffer annual severe bleaching by 2034 and, without drastic intervention, would be gone entirely by the year 2100.
Carlos M. Duarte, a marine ecologist at King Abdullah University of Science and Technology in Saudi Arabia says that in order to reverse these impacts, we must act right now.
“We have a very narrow window of time — basically a decade,” he said according to Scientific American. “The window is rapidly closing.”
And the impacts are being seen right here in Australia.
Half of the Great Barrier Reef’s coral has now been lost
The Great Barrier Reef has now lost half its corals, a sobering new study from the ARC Centre of Excellence for Coral Reef Studies has revealed.
Of the 340,000 square kilometre reef, more than 50% of the small, medium and large corals have been lost to coral bleaching events between 1995 and 2017, when this particular study concluded.
Devastatingly, the study does not take into account the mass bleaching event in early 2020, which exposed the southern part of the reef to record-breaking temperatures, and thus would have worsened these results again. In February, the highest-ever monthly sea surface temperatures were recorded on the reef since the Bureau of Meteorology began collecting this data in 1900.
“We used to think the Great Barrier Reef is protected by its sheer size — but our results show that even the world’s largest and relatively well-protected reef system is increasingly compromised and in decline,” the study’s co-author Professor Terry Hughes said of the findings.
Hopeful research has found ecosystems like the Great Barrier Reef are able to recover from bleaching events, however since coral is slow to grow, it can take parts of the reef around a decade to recover. The concern, of course, lies in the frequency in which these events are now occurring. If we’re unable to lower temperatures, we could be looking at a mass extinction not only of the coral itself but the vast marine life within.
“There is no time to lose — we must sharply decrease greenhouse gas emissions ASAP,” Hughes, along with lead researcher Dr Andy Dietzel, say.
What can scientists do about it?
Right now, efforts are being made to bring the Great Barrier Reef back into a healthy place. While some scientists continue to spread the word about the environmental efforts needed in order for sea temperatures to lower and steady, others are working to equip those who work on the reef to help the ecosystem rebuild, with a new practice called ‘coral gardening’.
Speaking to The Guardian, David Suggett, an associate professor at the University of Technology Sydney, said: “We’re trying to build a more sustainable and resilient reef economy, by equipping workers with the skills and tools to propagate corals from the good parts of the reef to help rebuild the poor parts of the reef, so that the ecosystem they rely on for their livelihoods is retained.”
Ultimately, we need to pursue efforts that limit the global temperature increase to 1.5°C, in line with the Paris Agreement on climate change. The International Union for Conservation of Nature (IUCN), says this would secure the “only chance for the survival of coral reefs globally”.
And while those knowledgeable experts continue to work on additional initiatives like 3D-printed reefs and artificial reef noise (Google it, it’s astounding), there is work to be done by all of us, yes, even you, as you read this.
How to help the Great Barrier Reef
For starters, conversations must continue around the effects, impacts and preventative strategies of climate change. We must not lose momentum and we must not tire in our fight for climate justice on a federal level. Where you can, donate your time, efforts and funds to climate-related causes, sign petitions against further environmental damage, and show up to climate rallies and protests.
If you find you’re lacking daily resources, change who you’re following on Instagram and seek out accounts that are doing the work to equip the masses with tools and resources to effect positive change. Over at The Latch, we love referring to Future Earth, Shit You Should Care About, and The Daily.
David Attenborough also joined Instagram in September 2020 and while his account is no longer active, he used his platform to educate and inspire his millions of followers with behind-the-scenes stories from his most recent Netflix documentary, A Life On Our Planet.
Furthermore, there is more work to be done at home — and while these efforts may be small, they contribute to a much greater picture. Look into these five easy switches for a more eco-friendly existence in 2021, switch your home energy to a green provider, and read up on regenerative travel as the way forward.
Read more stories from The Latch and subscribe to our email newsletter.