Study shows ocean acidification is having major impact on marine life

July 27, 2018 by Alan Williams, University of Plymouth
Corals, such as this table Acroporid, provide habitats for a wide range of fauna at a reference site where the CO2 concentration is currently 300ppm. Credit: Marco Milazzo

Carbon dioxide emissions are killing off coral reefs and kelp forests as heat waves and ocean acidification damage marine ecosystems, scientists have warned.

Writing in Scientific Reports, researchers say that three centuries of industrial development have already had a marked effect on our seas.

But if CO2 levels continue to rise as predicted, the coming decades and lowering seawater pH levels will have an even greater and potentially catastrophic impact.

Their predictions follow a comprehensive study of the effects of recently discovered volcanic CO2 seeps off Shikine Island, Japan, which is on the border of temperate and tropical climates.

Ocean currents in the area mean there are naturally low levels of surface water CO2, similar to those that would have been present before the global Industrial Revolution. However, the volcanic seeps indicate how rising CO2 levels will affect future ecology, both in the northwest Pacific Ocean and across the world.

Lead author Dr. Sylvain Agostini, Associate Professor at the University of Tsukuba Shimoda Marine Research Centre, said: "These CO2 seeps provide a vital window into the future. There was mass mortality of corals in the south of Japan last year, but many people cling to the hope that corals will be able to spread north. Therefore it is extremely worrying to find that tropical corals are so vulnerable to , as this will stop them from being able to spread further north and escape the damage caused by water that is too hot for them."

At a site with a CO2 concentration of 900ppm, corresponding to conditions predicted for 2100, the high CO2 favors the growth of low profile algae that covers all the available substrate, and inhibits the growth of corals and other habitat forming species. This leads to a drastic decrease in biodiversity. Credit: Marco Milazzo

The research was led by scientists at the University of Tsukuba in Japan, the University of Plymouth in the UK and the University of Palermo in Italy.

It involved teams of SCUBA divers who carried out investigations along underwater CO2 gradients created by volcanic seeps, recording how the fauna and flora respond to seawater acidification.

They found that while a few plant species benefitted from the changing conditions, they tended to be smaller weeds and algae that blanket the seabed, choking corals and lowering overall marine diversity.

These species, and some smaller marine animals, are thriving because they are more tolerant to the stress posed by rising levels of CO2.

Jason Hall-Spencer, Professor of Marine Biology at the University of Plymouth, said: "Our research site is like a time machine. In areas with pre-Industrial levels of CO2 the coast has an impressive amount of calcified organisms such as corals and oysters. But in areas with present-day average levels of surface seawater CO2 we found far fewer corals and other calcified life, and so there was less biodiversity. It shows the extensive damage caused by humans due to CO2 emissions over the past 300 years and unless we can get a grip on reducing CO2 emissions we will undoubtedly see major degradation of coastal systems worldwide."

Professor Kazuo Inaba, former director of the Shimoda Marine Research Centre, added: "Local fishermen are keen to know how ocean acidification will affect their livelihoods. Currents flowing past Japan bring waters that have naturally low levels of CO2 and fish benefit from the array of calcified habitats around our islands. If we are able to meet the Paris Agreement targets to limit emissions we should be able to limit further damage to kelp forests, and all ."

Explore further: Internal control helps corals resist acidification

More information: Sylvain Agostini et al, Ocean acidification drives community shifts towards simplified non-calcified habitats in a subtropical−temperate transition zone, Scientific Reports (2018). DOI: 10.1038/s41598-018-29251-7

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16 comments

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NoLeads
1.4 / 5 (10) Jul 27, 2018
because Fukushima after 10+ years has no real effect on our connected Oceans.
too bad the University of Leeds proved that carbon is incredibly healthy for our environment & agriculture while being responsible for the massive plankton growth we got this year and the earth showing a growing green effect.
is this propaganda allowed in the science forum? why?
the distraction of the masses must discontinue in the thinking mind. fk money.
have honour & integrity.
aksdad
1.9 / 5 (9) Jul 27, 2018
Interesting study; one of the few that examine organisms in the ocean rather than in aquariums. However, it tells us very little, if anything at all, about future impacts of CO2 on ocean life. Not a lot of people know that seawater CO2 concentration varies seasonally—40% or so—yet reefs remain healthy. For example see here:

https://www.pmel....ent+Reef

The long-term rate of "acidification" is so small that it's unlikely to overwhelm the seasonal changes, even by 2100. Try to see the long-term trend at the above link. It's minuscule. Also notice that the data only goes back a decade or less. There aren't a lot of stations regularly monitoring seawater CO2, and even fewer monitoring pH so it's impossible to make any predictions about the future. That doesn't stop alarmists from making predictions, though.

Here's a list of monitoring stations:

https://www.pmel....map/text
howhot3
4.4 / 5 (7) Jul 27, 2018
Oh my gosh. Such lameness among the climate denier goon squad. Forget what the above losers say and just read the article.

Bozo's like the above clowns couldn't count 3+C on a 100C thermometer in a 24C air conditioned room.
unrealone1
1 / 5 (6) Jul 28, 2018
The acidity of the ocean during the Jurassic period was, when the CO2 levels where "3000" ppm.
Whart1984
1.5 / 5 (8) Jul 28, 2018
The CO2 levels reached 1300 ppm in eocene, i.e. relatively recently before 35 mil. years. Both marine, both terrestrial life flourished during it, for example whales evolved during this period, because warm oceans were full of food. And corals also managed to survived it, so that we have large reserve with 420 ppm of CO2 today.

Of course that CO2 levels leave imprint to marine life, as the acidic water prefers the proliferation of tiny crustaceans (remember the whales) and jellyfishes without carbonate shells. The jellyfishes are currently a calamity in oceans, but they're also edible.
Thorium Boy
1.6 / 5 (7) Jul 29, 2018
This is what happens when you ignore real pollution and concentrate on controlling harmless C02. Remember "acid rain?" Remember when the greenloons were on about that? They may have been right. They should have stuck to that.
greenonions1
5 / 5 (5) Jul 29, 2018
Notleads
too bad the University of Leeds proved that carbon is incredibly healthy for our environment

From the article
Carbon dioxide emissions are killing off coral reefs and kelp forests


leetennant
5 / 5 (5) Jul 29, 2018
What we've said from the beginning - rising sea temps will be nothing compared to the huge negative impact of acidification.
Surveillance_Egg_Unit
1.8 / 5 (5) Jul 30, 2018
The Global Warming/C.C. folks should get on an air polluting jet plane to Beijing and give the Chinese government a warning of their displeasure that China is the number one polluter of plastics and other garbage. And that all of the garbage that China dumps into the seas will be returned to them by special delivery.

https://www.tripl...e-patch/

greenonions1
5 / 5 (2) Jul 30, 2018
Surveillance
The Global Warming/C.C. folks should get on an air polluting jet plane to Beijing
Why don't you do that Surveillance? Do you think that only people who follow the science of climate change should be concerned about the pollution of plastics in our oceans? Do you not care about the pollution of plastics in our oceans?
b_man
1 / 5 (3) Jul 30, 2018
No it isn't
gkam
2.3 / 5 (3) Jul 30, 2018
How many more huge wildfires will we have this year?
They rage all over the Earth this year.
What happens NEXT year?
barakn
5 / 5 (5) Jul 30, 2018
Interesting study; one of the few that examine organisms in the ocean rather than in aquariums. However, it tells us very little, if anything at all, about future impacts of CO2 on ocean life. Not a lot of people know that seawater CO2 concentration varies seasonally—40% or so—yet reefs remain healthy. -aksdad
Higher CO2 means both the lows and highs will be higher - the average CO2 concentration will be higher. If coral is damaged when it swings high, the coral will have less time to recuperate when it swings low, because the low will also be higher.
barakn
5 / 5 (5) Jul 30, 2018
Also notice that the data only goes back a decade or less. There aren't a lot of stations regularly monitoring seawater CO2, and even fewer monitoring pH so it's impossible to make any predictions about the future. -aksdad

If you think that pH is going to rise and CO2 levels are going to drop as atmospheric levels keep rising, you are even more stupid than I thought.
barakn
5 / 5 (5) Jul 30, 2018
The CO2 levels reached 1300 ppm in eocene, i.e. relatively recently before 35 mil. years. Both marine, both terrestrial life flourished during it, for example whales evolved during this period, because warm oceans were full of food. -Wart1984/Zephir
Strawman argument. Scientists are very well aware that CO2 levels were higher than today. The real issue is the RATE at which CO2 levels are changing and whether coral can adapt quickly enough. And unlike you, the scientists are aware of major extinction events in marine life. The Tabulata and the Rugosa, two entire orders of coral, became extinct during the Permian–Triassic extinction event. So the mere fact of higher CO2 levels in the past does not mean that corals are safe.
barakn
5 / 5 (6) Jul 30, 2018
Remember "acid rain?" -Thorazine Boy
A problem that largely ended (in the U.S) with the addition of scrubbers that remove sulfur dioxide from coal-fired power plants, the removal of sulfur from diesel fuel, and emission controls on vehicles to reduce production of nitrogen oxides. An environmental problem solved by regulations. Are you sure you want to remind people of this?

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