In January this year when David Spratt took a look at whether tipping points had already been passed for critical climate systems he found that coral reefs were in death spiral. From reef ecology scientists:
“The time between recurrent events is increasingly too short to allow a full recovery of mature coral assemblages, which generally takes from 10 to 15 years for the fastest growing species and far longer for the full complement of life histories and morphologies of older assemblages.”
Mass bleaching occurred in 1998, 2002, 2016, 2017 and 2020.
Multiple lines of evidence suggest the current physical conditions will cause decreasing extent and ecosystem collapse along the Great Barrier Reef at the current level of warming:
- Melbourne-based researchers showed in 2017 that the hotter water conditions that drove the severe bleaching in 2016 will occur on average one year in three at 1.2°C, and two years in every three at 1.5°C.
- In 2021, researchers concluded that at 1.5°C, severe bleaching events would occur on average three times per decade.
See also David Spratt and Ian Dunlop Climate Dominoes: Tipping point risks for critical climate systems
Now in 2022, during a La Niña event, there has been further bleaching, plus a Reef survey which ostensibly showed recovery in ‘reef cover’. Imogen Zethoven addresses this ostensible counter-intuitive information in The Great Barrier to understanding the Reef.
The answer is simple. Regrowth has come from one group of species: Acropora. They grow rapidly after disturbance, but are also the most vulnerable to damage from cyclones and further coral bleaching. Moreover they are the preferred diet of the coral-eating Crown-of-Thorns starfish.
So the ‘recovery’ reduces diversity and increases vulnerability.
For further detail see Annual Summary Report of Coral Reef Condition 2021/22 which may be found on the Great Barrier Reef Marine Park Authority Reef health site.
On February 2 this year Zethoven tore into the Morrison Government in Biggest barrier to saving the Reef is a political class in climate denial. The government had just announced an extra $1 billion to spend over nine years on the GBR, strategically just ahead of official visits by representatives from UNESCO and the International Union for the Conservation of Nature (IUCN) acting as advisors to the World Heritage Committee who are due to make a decision on whether the GBR will be included on the List of World Heritage in Danger. Readers will recall that last year the Morrison government had sent Minister for Environment Sussan Ley scurrying around Europe, lobbying to prevent such a listing. Zethoven says:
- There was no moment of self-consciousness, no flicker of unease when the Prime Minister announced that “We’re investing in this Reef for generations and generations to come.”
The PM was announcing $1 billion over nine years for the Great Barrier Reef. Hoping that no-one would mention his government’s climate policies that will drive the Reef to extinction in our lifetimes (that is, if every other country made the same effort as his government), he chose to focus on all the other issues.
A few days earlier, the Bureau of Meteorology (BoM) had just confirmed December 2021 as the hottest December on the Reef since records began.
As Zethoven reports, the mission duly arrived in March, and was shepherded around the reef to see restitution and protection initiatives. Mission members were not available to be interviewed unminded, and visited just two reefs, which Zethoven says were “green”. I assume that meant green as in this image, which showed the results of a survey after the new bleaching event, which occurred from 12-23 March:
There was plenty going on in late March. A few days into the mission PM Scott Morrison and his Deputy Barnaby Joyce were announcing $6 billion worth of new and expanded dams at Hells Gate on the Upper Burdekin and Urannah Dam on the Bowen River also in the Burdekin region. Meanwhile:
On day two of the mission, Resources Minister Angus Taylor visited Gladstone to announce $50.3 million for seven “priority” gas projects while reports of Reef bleaching were coming in thick and fast. The Minister made his announcement the day after the UN Secretary-General Antonio Guterres named Australia as a “hold out” amongst a group of nations that had announced meaningful emission reductions by 2030 to keep alive the Paris Agreement’s warming limit of 1.5°C.
Zethoven does cite the 2018 IPCC Special Report on 1.5°C which says that limiting to 1.5°C will result in a further 70-90 per cent loss of the world’s coral reefs. Strangely she did not cite new research which has found that with 1.5°C, highly likely from 2030, coral reefs all over the world will die off. See Adele M Dixon et al Future loss of local-scale thermal refugia in coral reef ecosystems:
See also CarbonBrief’s Last refuges for coral reefs to disappear above 1.5C of global warming, study finds:
- The study projects that, at 1.5C, coral reefs will be able to survive marine heatwaves in only two locations: Polynesia and the Coral Triangle, a marine area in the Pacific Ocean including the waters of Indonesia, Malaysia, the Philippines, Papua New Guinea, Timor Leste and the Solomon Islands.
Australia’s reef scientists were not involved, but agree with the findings.
I have heard Zethoven suggest on radio that with 1.5°C the GBR would be alright, or similar. Certainly Adam Bandt and Larissa Waters have been saying the 1.5°C will save the reef.
This is offering false hope. I’m with David Spratt, coral reefs are in a death spiral. That is not 100% certain, but is way more than likely.
There is immense sadness in realising that the planet has changed irrevocably in the Anthropocene. Amy Brady and Tajja Isen asked 19 writers express their thoughts and feelings about places they have loved which have now gone forever:
Starting from the premise that the personal is planetary and that the planet has changed irrevocably, this collection of essays considers the climate crisis from the perspective of the individual.
What does climate change mean at the level of the everyday when the places we love and the geographies that shaped us are changing in real time?
Amy Brady and Tajja Isen invited 19 writers to take this question and run with it, making the end result an eclectic and beautifully written anthology marked by sadness and grief.
There’s wonder too, and occasional glimpses of possibility, but in the end:
- these compelling and at times heartbreaking essays cover a lot of ground, but they start from the same assumption: the world as we knew it is gone. To quote Dorothy from the Wizard of Oz: “We’re not in Kansas anymore.”
But there’s no yellow brick road for us. And if even if there were, what’s to go home to? As Amy Brady and Tajja Isen remind us, temperatures now regularly reach the upper nineties in the Sunflower State. And in the coming decades, Kansas is expected to see a lot more days above 100°F.
There is an issue here as to how we cope when hope is becoming more difficult. Bill McGuire looking at our dilemma more pragmatically says:
- A middle of the road route would be to no one’s advantage – so, as for most situations wherein the risk is hard to quantify, there is only one sensible way forward: to hope for the best, while preparing for the worst.
There is nothing wrong with trying to restore and hang onto the past, but our stewardship should also be looking for the best outcomes in the future. This is out of my patch but for some time I have had the thought that we should we look at a larger scale ‘botanical gardens’ concept either in aquariums, or in situ, which preserves reef species to rebuild as well as continuing the tourist industry. Obviously we can’t keep 3,000 reefs spread over the size of Italy, but isolated experiments in labs and at selective reef stations seem inadequate.
I had thought of government funding, but now IBM and Microsoft have come up with a new startup, The Reef Company. It plans 2500 reefs, each measuring 4 square kilometres, over the next 10, with the first in the water by December 2022.
The company is based in Portugal and supported by an investor group from Costa Rica. One of the planned reefs is in Malaysia. No mention of the GBR.
See Start-up plans 2500 artificial coral reefs to fight climate change (probably pay-walled).
I wonder whether we have told them that it’s all AOK here, that the mighty GBR is not in danger.
Update September 4, 2022:
The CarbonBrief Q&A The IPCC’s sixth assessment on how climate change impacts the world of 22 February 2022 cites the IPCC AR6 WG2: Impacts, adaptation and vulnerability saying:
- Climate change has already caused “substantial damages and increasingly irreversible losses, in terrestrial, freshwater and coastal and open ocean marine ecosystems”.
On coral reefs:
- There is high confidence that with warming above 1.5C, reefs are “under threat” of reaching erosion rates that are larger than the rate at which new corals can grow.
And, as an example of a regional case study:
the Australasia chapter includes a box entitled “The Great Barrier Reef in Crisis”, which states with high confidence that the world’s largest coral reef “is already severely impacted by climate change”.
Time to face reality and work on Plan B.