Ocean acidification to hit levels not seen in 14 million years

July 23, 2018 by Julia Short, Cardiff University
Credit: CC0 Public Domain

New research led by Cardiff University has shown that under a 'business-as-usual' scenario of carbon dioxide (CO2) emissions, ocean acidification is likely to hit unprecedented levels.

Ocean acidification occurs when CO2 from the atmosphere is absorbed by seawater, resulting in more acidic water with a lower pH.

Around a third of the CO2 released by burning coal, oil and gas gets dissolved into the oceans. Since the beginning of the industrial era, the has absorbed around 525 billion tons of CO2, equivalent to around 22 million tons per day.

The rapid influx of CO2 in to the oceans is severely threatening marine life, with the shells of some animals already dissolving in the more acidic seawater.

In their new study, published in the journal Earth and Planetary Science Letters, the researchers set out to reconstruct levels of ocean acidity and atmospheric CO2 levels over the past 22 million years.

They did so by studying the fossils of tiny marine creatures that once lived near the ocean surface, specifically using the chemistry of their shells to monitor the acidity of the seawater in which the creatures lived.

Based on this information, the researchers were able to put their new records of pH and CO2 levels in context of the range of future carbon emission scenarios that are recognised by the Intergovernmental Panel on Climate Change (IPCC).

Under a 'business-as-usual' future scenario where we continue to emit CO2 at the same rate as we do today, atmospheric CO2 would be near 930 parts per million in the year 2100, compared to around 400 parts per million today.

Similarly, the pH of the oceans would be less than 7.8 in 2100 compared to a pH of around 8.1 today. This is very significant as the pH scale is logarithmic, meaning a drop of just 0.1 pH units represents a 25% increase in acidity.

These levels of atmospheric CO2 and have not been since the Middle Miocene Climatic Optimum period around 14 million years ago, when global temperatures were around 3°C warmer than today as a result of the Earth's natural geological cycle.

Lead author of the study Dr. Sindia Sosdian, from Cardiff University's School of Earth and Ocean Sciences, said: "Our new geological record of shows us that on our current 'business as usual' emission trajectory, oceanic conditions will be unlike have experienced for the last 14 million years."

Professor Carrie Lear, co-author of the study, added: "The current pH is already probably lower than any time in the last 2 million years. Understanding exactly what this means for marine ecosystems requires long-term laboratory and field studies as well as additional observations from the fossil record."

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oldephartte
1 / 5 (11) Jul 23, 2018
" global temperatures were around 3°C warmer than today as a result of the Earth's natural geological cycle." Uh - huh. And are today's temperatures not part of a geological cycle ? The problem for any layman reading about climate and temperature change is simple : climate changes. Are today's conditions affected by CO2 levels ? All that is available are scenarios which may or may not mean anything. Correlation is not causation. Kindly note readings of past ph levels are taken from then current life. That means such levels will not extinguish it.

691Boat
4.6 / 5 (11) Jul 23, 2018
" global temperatures were around 3°C warmer than today as a result of the Earth's natural geological cycle." Uh - huh. And are today's temperatures not part of a geological cycle ? The problem for any layman reading about climate and temperature change is simple : climate changes. Are today's conditions affected by CO2 levels ? All that is available are scenarios which may or may not mean anything. Correlation is not causation. Kindly note readings of past ph levels are taken from then current life. That means such levels will not extinguish it.


Please, kindly inform this "layman" about the rate of change in the past versus today? Thanks in advance!
zz5555
4.7 / 5 (12) Jul 23, 2018
Last day of vacation, so what the heck.

Nice Gish gallop old one. Being old doesn't mean you can just stop thinking and coast - that's how old people get caught by con men.

And are today's temperatures not part of a geological cycle?

Today's temperatures are a combination of natural and man made factors - man made are mostly increased atmospheric CO2 levels and the resultant positive feedbacks associated with that. In fact, it's very well known that the natural factors since ~1970 have been working to cool global temperatures slightly, so that humans are known to have caused > 100% of the warming since then.

The problem for any layman reading about climate and temperature change is simple : climate changes.

The important thing to remember is that climate always changes - for a reason. It isn't just a random change. Sometimes the sun puts out more, or less, energy. Or the earth's orbit is closer to the sun. (Continued)
zz5555
4.7 / 5 (12) Jul 23, 2018
Or continents change position, which affects the ocean currents. Or CO2 levels in the atmosphere increase or decrease. Or humans clear a bunch of land, changing the earth's albedo. There's always some underlying reason why the climate changes. And these are quite well understood.

Are today's conditions affected by CO2 levels?

Yes, quite profoundly. And as abundant evidence shows, CO2 has always had a large effect on the climate.

All that is available are scenarios which may or may not mean anything. Correlation is not causation.

Actually, there's a great deal more available than "scenarios". Direct measurements show conclusively that humans are having a large effect on the climate. Correlate may not be causation, but causation sure as hell is causation. ;)

(Continued)
zz5555
4.6 / 5 (10) Jul 23, 2018
Kindly note readings of past ph levels are taken from then current life. That means such levels will not extinguish it.

Nice strawman. No one has said that all life will die due to this. But a lot of life forms will become extinct. Probably not humans, but a lot of them will likely be killed by man made climate change. Being old, you might not care. But if you have kids or grandchildren, they will definitely be affected by it. And some will likely die from the changes coming - either directly by climate change or by changes to civilization that will be required.

It's also likely to cost much, much, much more to deal with the changes in the future than to prevent some or all of them now. That means much higher taxes in the future. Again, as an old person, you might not care. Some of us (even us old people) would, however, like to prevent some of the worst problems if we can rather to saddle the future with our problems.
zz5555
4.6 / 5 (9) Jul 23, 2018
It's also interesting to point out that the change to renewable power is going to come whether you like it or not. Renewables are cheaper than most forms of energy (I think only natural gas can compete) and are going to continue getting cheaper. Countries that invest in these technologies will likely do well selling the technologies to other countries. It's seemed to me that anyone that supports the older technologies is damaging their respective country. Which, again as an old person, you might not care about. I think future generations will see these people for who they are, though.

(There's also the likelihood that rejecting mitigation efforts will bring about the one world government that main claim to fear, but I've been on my soapbox enough ;).
Zzzzzzzz
3.7 / 5 (3) Jul 23, 2018
Perhaps the Old Fart is so old that he is dead. He certainly smells like it - much worse than any fart.. An uneducated dead thing.
leetennant
5 / 5 (8) Jul 23, 2018
" global temperatures were around 3°C warmer than today as a result of the Earth's natural geological cycle." Uh - huh. And are today's temperatures not part of a geological cycle ?


I once met a person with lung cancer who didn't smoke so therefore smoking can't cause cancer.
howhot3
4.5 / 5 (8) Jul 24, 2018
" global temperatures were around 3°C warmer than today as a result of the Earth's natural geological cycle." Uh - huh. And are today's temperatures not part of a geological cycle 


I once met a person with lung cancer who didn't smoke so therefore smoking can't cause cancer.


I noticed that too. Odd to begin with a false claim and then carry-on with some fantasy speculation.

I hate to be the doom-and-gloom realist in the bunch, but rapid ocean acidification like what is occurring now is another brick in the extinction apocalypse that we seem to be on track towards. It's freaky that this isn't the most important issue of the day, but we humans are easily occupied with crap that doesn't matter.

Once trump and the 10 braincell morons appointies are out of office, the grownups can take over and do what has to be done; ban human CO2 production.

Fernando L
not rated yet Jul 24, 2018
I would repeat this study at peak 630 ppm CO2 concentration. The CMIP5 climate model runs fed the RCP8.5 pathway were unrealistic. The model assumed fast recarbonization of the economy, and excessive fossil fuel supply, and very low renewable and nuclear use. It's hard to blame the model, because the IPCC had decided to set the 8.5 watts per square meter forcing target. Therefore the team simply forced it with unrealistic CO2 and CH4 emissions profiles (and concentrations). A better figure would be a 630 ppm peak, although I've read papers with lower figures.
antialias_physorg
5 / 5 (3) Jul 24, 2018
Renewables are cheaper than most forms of energy (I think only natural gas can compete)

Not even that anymore. And being a finite resource there is no way natural gas can compete long term in any case.
MR166
2.3 / 5 (6) Jul 24, 2018
The combination of regulations and renewables have made coal plants uneconomical. Due to renewables there is a big demand for intermittent power that only gas powered plants can fulfill. Since the supply of nat gas is much more limited than coal the end result will be gas shortages and power interruptions. Of course, these interruptions will be blamed on the greedy power companies and not poor policy decisions.

rrwillsj
2.3 / 5 (4) Jul 24, 2018
Oh mister denial shill as long as you're denying climate reality? And inventing lies to deny environmentalist warnings of impending catastrophe?

Here's a doom and gloom warning for you to disregard.

As you rive too close to the precipice, you sneer at my waving and shouting at you to veer away.

Cause obviously, you are doing just fine! You don't see any problem, as you steer in the direction of the edge of the cliff and put the pedal to the metal..

When your gas-guzzler at high-speed, bears you off the edge into space? Laughing, you dismissively wave back at my frantic attempt to stop you.

Like you're going to listen to any advice a tree-hugging loon might have to impart.

As you achieve apogee, you tell yourself how smart you are cause so-far, so-good!

As the vehicle your in tilts down and starts to fall? You insist that there is no discernible problem so far! And how happy you were to avoid eco-nut warnings.

All the way down...
antigoracle
1 / 5 (6) Jul 24, 2018
Renewables are cheaper than most forms of energy (I think only natural gas can compete)

Not even that anymore. And being a finite resource there is no way natural gas can compete long term in any case.

Another ignorant Chicken Little Jackass, brays.
Hey Jackass, check who are paying the highest prices for power. It's those, in countries that are heavily dependent on your "cheap" renewables..i.e..Denmark, Germany, Australia....
So, keep braying, you ignorant jackass.
antigoracle
1.5 / 5 (8) Jul 24, 2018
The combination of regulations and renewables have made coal plants uneconomical. Due to renewables there is a big demand for intermittent power that only gas powered plants can fulfill. Since the supply of nat gas is much more limited than coal the end result will be gas shortages and power interruptions. Of course, these interruptions will be blamed on the greedy power companies and not poor policy decisions.


This is exactly what has happened in Australia, where the poor now bear the brunt of the AGW Cult's ignorance. --- https://www.bloom...st-power
Fernando L
2.3 / 5 (3) Jul 24, 2018
The combination of regulations and renewables have made coal plants uneconomical.



Coal plants seem to have decent returns in India. I looked up worldcoal dot com and saw quite a few articles about new power plants, including the following:

"Doosan Heavy Industries & Construction announced on December 26 (2016) that its Indian affiliate, Doosan Power Systems India (DPSI), received Notices of Award for projects to construct two thermal power plants worth US$2.3 billion in all from the Uttar Pradesh State government's state power company."

MR166
4.3 / 5 (3) Jul 24, 2018
Fernando I was referring to coal plants in the US.
howhot3
5 / 5 (4) Jul 25, 2018
From the article;
Under a 'business-as-usual' future scenario where we continue to emit CO2 at the same rate as we do today, atmospheric CO2 would be near 930 parts per million in the year 2100, compared to around 400 parts per million today.
Similarly, the pH of the oceans would be less than 7.8 in 2100 compared to a pH of around 8.1 today. This is very significant as the pH scale is logarithmic, meaning a drop of just 0.1 pH units represents a 25% increase in acidity.

Yikes. I remember protesting at 300ppm and no more. Man... Was I sadly optimistic. You climate deniers have won! Won the "your going to hell" award obviously.
antigoracle
1 / 5 (1) Jul 26, 2018

Yikes. I remember protesting at 300ppm and no more. Man... Was I sadly optimistic. HAWW....HEE....HAWW.....HEEE.
-- howshot3...AKA..howShat da Turd

Is this the time you went to New York, spewing CO2 all the way, just to get a sniff of the methane from the ass of your FALSE "PROFIT" Al ?
Why won't you tell us, how and when you stopped burning fossil fuels, so that us Heretics can join you in saving the world? Or, you can just keep braying, Jackass.
humy
5 / 5 (2) Jul 26, 2018
The combination of regulations and renewables have made coal plants uneconomical. Due to renewables there is a big demand for intermittent power that only gas powered plants can fulfill.

You obviously haven't heard of this newfangle thing called the "Battery".
Also look up "supergrid";

https://en.wikipe...per_grid

And also google "marine current power" and also "biofuels", neither of which are intermittent;

https://en.wikipe...nt_power
SwamiOnTheMountain
not rated yet Aug 02, 2018
The warmer water gets, the less CO2 it can absorb.
The ocean is getting warmer.
The ocean is absorbing less CO2.
CO2 is not causing an ocean increase in acidification.
#red herring

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