Warmer waters "good for coral growth"

Doing OK?

It’s rare to find anyone with a good word to say about warmer temperatures. If you believe the media and the consensus boys, the global temperature we had in year x (where x is any random year you care to choose) was the “right” one for the planet, and any change, whether up or down, is invariably bad.

We’ve already seen that temperatures heading down generally causes more hardship, but why should a modicum of warming immediately be bad? There is no “right” temperature for the planet – such a construct is pure alarmist fiction.

So it is interesting to read that a new study in Science (peer-reviewed, for what that’s worth these days) shows that corals around Australia are thriving in slightly warmer temperatures:

A GOVERNMENT-RUN research body has found in an extensive study of corals spanning more than 1000km of Australia’s coastline that the past 110 years of ocean warming has been good for their growth.

The findings undermine blanket predictions that global warming will devastate coral reefs, and add to a growing body of evidence showing corals are more resilient than previously thought, up to a certain point.

The study by the commonwealth-funded Australian Institute of Marine Science, peer-reviewed findings of which are published in the leading journal Science today, examined 27 samples from six locations from the West Australian coast off Geraldton to offshore from Darwin.

At each site, scientists took cores from massive porites corals – similar to a biopsy in humans – and counted back to record their age in much the same way tree rings are counted. Although some cores extended back to the 18th century, they focused on the period from 1900 to 2010.

The researchers found that, contrary to their expectations, warmer waters had not negatively affected coral growth. Quite the opposite, in fact: for their southern samples, where ocean temperatures are the coolest but have warmed the most, coral growth increased most significantly over the past 110 years. For their northern samples, where waters are the warmest and have changed the least, coral growth still increased, but not by as much.

“Those reefs have actually been able to take advantage of the warmer conditions,” said Janice Lough, a senior AIMS research scientist and one of the study’s authors.

Maria Byrne, a professor of marine biology at Sydney University, said after reading the paper that its findings “made perfect sense”. “Temperature rules metabolism, so it’s a no-brainer that if you get more temperature you will get more metabolism.”

She compared the findings to studies of sea urchins, where higher temperatures had been shown to offset the negative effects of ocean acidification, and to commercial aquaculture farms, in which some organisms are deliberately raised in warmer water to increase their growth rate.

The key question is how warm the water can get before the positive effects are reversed.

Lab studies have typically measured the effect of short-term, rapid changes in temperature and water chemistry; these mimic, for example, coral-bleaching events that are known to be devastating. Much harder to measure are the long-term effects of gradual warming, such as is caused by climate change.

A recent paper published in the journal Nature Climate Change, reported in The Australian, showed Zooxanthellae – the symbiotic organisms that live inside corals – can adapt much better to warming water than was previously thought [see here for ACM’s post on this – Ed] It is also known corals can, to a degree, change their Zooxanthellae with changing conditions. (source)

The Science abstract can be found here, a quote from which is set out below:

“In situ studies have documented alarming recent declines in calcification rates on several tropical coral reef ecosystems. We show there is no widespread pattern of consistent decline in calcification rates of massive Porites during the 20th century on reefs spanning an 11° latitudinal range in the southeast Indian Ocean off Western Australia.”

UPDATE: Scientific American spins this into the following headline:

 “Temperatures – not acid – could cook coral to death”

No, really, “cook coral to death” – that’s what it says. Check the link.


  1. Bob Linville via Facebook says:

    Here in southern Indiana, we are enjoying a “warmer than uasual” winter so far…and I am LOVING it. Give me all of the global warming that you don’t want!

  2. Bruce of Newcastle says:

    Comes at least partly from the Australian Institute of Marine Science in Townsville, who seem professional scientists not political activists. They have a nice rivalry going with Professor Ove’s catastrapharians at UQ.

    Bit like sensible NASA GSFC vs ‘coal-death-trains’ NASA GISS.

  3. The biggest threat to coral reefs isn’t warm water but Greenpeace. Back in 2005 they were forced to pay a $7,000 fine for damaging a coral reef at Tubbataha Reef Marine Park, in the Sulu Sea, Philippines. One hundred sqm of reef was damaged when their flagship Rainbow Warrior II ran aground destroying World Heritage listed corals.

  4. Simon Colwell says:

    Reminds me of what Peter Ridd said on Andrew Bolt’s tv show, namely that some of the corals that grow on the Barrier Reef also grow in Papua new Guinean waters and that the ones off PNG are LARGER because the water is warmer. So much for warmer waters being bad for corals. He also said that where corals have been dying it’s because sea levels have FALLEN. So much for the alarmist drivel about rising sea levels too.

  5. “Maria Byrne, a professor of marine biology at Sydney University, said after reading the paper that its findings “made perfect sense”… She compared the findings to studies of sea urchins, where higher temperatures had been shown to offset the negative effects of ocean acidification…”

    Please tell me a professor of marine biology knows that oceans are alkaline. There is no such thing as ocean ‘acidification’. They may become less alkaline, but that is still not acid.

  6. Louis Jepsen says:

    My father-in-law was a strawberry farmer here in Willamette Valley, Oregon. His strawberries grown in 1940’s and ’50’s were ripe in the middle of May and he always worried they would rot on the vine because his pickers were school kids and school didn’t let out till second week in June. Now the strawberries don’t get ripe until the middle of July. Just a meaningless observation I suppose.

    • The strawberries were bred that way, Louis … needed to ripen later when more workers were available. You may not have noticed, but they are also huge and tasteless compared to my dad’s berries of the 50’s.

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