World ocean systems undermined by climate change by 2100

Oct 15, 2013

An ambitious new study describes the full chain of events by which ocean biogeochemical changes triggered by manmade greenhouse gas emissions may cascade through marine habitats and organisms, penetrating to the deep ocean and eventually influencing humans.

Previous analyses have focused mainly on and acidification, considerably underestimating the biological and social consequences of . Factoring in predictable synergistic changes such as the depletion of dissolved oxygen in seawater and a decline in productivity of ocean ecosystems, the new study shows that no corner of the world ocean will be untouched by climate change by 2100.

"When you look at the world ocean, there are few places that will be free of changes; most will suffer the simultaneous effects of warming, acidification, and reductions in oxygen and productivity," said lead author Camilo Mora, assistant professor at the Department of Geography in the College of Social Sciences at the University of Hawai'i at Manoa (UH Manoa). "The consequences of these co-occurring changes are massive—everything from species survival, to abundance, to range size, to body size, to species richness, to ecosystem functioning are affected by changes in ocean biogeochemistry."

The human ramifications of these changes are likely to be massive and disruptive. Food chains, fishing, and tourism could all be impacted. The study shows that some 470 to 870 million of the world's poorest people rely on the ocean for food, jobs, and revenues, and live in countries where ocean goods and services could be compromised by multiple ocean biogeochemical changes.

Mora and Craig Smith with UH Manoa's School of Ocean and Earth Science and Technology (SOEST) worked with a 28-person international collaboration of climate modelers, biogeochemists, oceanographers, and social scientists to develop the study, which is due for publication October 15 in the scientific journal PLOS Biology.

The researchers used the most recent and robust models of projected climate change developed for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) to inform their analysis. They quantified the extent of co-occurrence of changes in temperature, pH, oxygen, and primary productivity based on two scenarios: a business-as-usual scenario wherein atmospheric CO2 concentrations could reach 900 ppm by 2100, and an alternative scenario under which concentrations only reach 550 ppm by 2100 (representing a concerted, rapid CO2 mitigation effort, beginning today).

They discovered that most of the world's ocean surface will be simultaneously impacted by varying intensities of ocean warming, acidification, oxygen depletion, or shortfalls in productivity. Only a very small fraction of the oceans, mostly in polar regions, will face the opposing effects of increases in oxygen or productivity, and nowhere will there be cooling or pH increase.

"Even the seemingly positive changes at high latitudes are not necessary beneficial. Invasive species have been immigrating to these areas due to changing ocean conditions and will threaten the local species and the humans who depend on them," said co-author Chih-Lin Wei, a postdoctoral fellow at Ocean Science Centre, Memorial University of Newfoundland, Canada.

The researchers assembled global distribution maps of 32 and biodiversity hotspots to assess their potential vulnerability to the changes. As a final step, they used available data on human dependency on ocean goods and services and social adaptability to estimate the vulnerability of coastal populations to the projected ocean biogeochemical changes.

"Other studies have looked at small-scale impacts, but this is the first time that we've been able to look the entire and how co-occurring stressors will differentially impact the earth's diverse habitats and people," said co-author Andrew Thurber, a postdoctoral fellow at Oregon State University. "The real power is in the quantitative, predictive approach using IPCC climate models that allow us to see how much it will all change, and also how confident we can be in our estimates."

By 2100, global averages for the upper layer of the ocean could experience a temperature increase of 1.2 to 2.6° C, a dissolved oxygen concentration reduction of ~2% to 4% of current values, a pH decline of 0.15 to 0.31, and diminished phytoplankton production by ~4% to 10% from current values. The seafloor was projected to experience smaller changes in temperature and pH, and similar reductions in dissolved oxygen.

Of the many marine habitats analyzed in the study, researchers found that coral reefs, seagrass beds, and shallow soft-bottom benthic habitats would experience the largest absolute changes in ocean biogeochemistry, while deep-sea habitats would experience the smallest changes.

Co-author Lisa Levin, a professor at Scripps Institution of Oceanography at the University of California, San Diego, notes: "Because many deep-sea ecosystems are so stable, even small changes in temperature, , and pH may lower the resilience of deep-sea communities. This is a growing concern as humans extract more resources and create more disturbances in the deep ocean."

"The deep-sea floor covers most of the Earth's surface and provides a whole host of important ecosystem services including carbon sequestration in seafloor sediments, buffering of ocean acidity, and providing an enormous reservoir of biodiversity," said Smith. "Nonetheless, very little attention has been paid to modeling the effects of climate change on these truly vast ecosystems. Perhaps not surprisingly, many deep seafloor ecosystems appear susceptible to the effects of climate warming over the next century."

"The impacts of climate change will be felt from the surface to the seafloor. It is truly scary to consider how vast these impacts will be," said co-author Andrew K. Sweetman, who helped to convene the original team of investigators and now leads the deep-sea ecosystem research group at the International Research Institute of Stavanger, Norway. "This is one legacy that we as humans should not be allowed to ignore."

Explore further: Scientists warn of 'deadly trio' risk to ailing oceans

More information: Mora C, Wei C-L, Rollo A, Amaro T, Baco AR, et al. (2013) Biotic and Human Vulnerability to Projected Changes in Ocean Biogeochemistry over the 21st Century. PLoS Biol 11(10): e1001682. doi:10.1371/journal.pbio.1001682

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User comments : 19

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shavera
4.6 / 5 (10) Oct 15, 2013
No one lives there, so no one has responsibility to take care of it? Is that the argument then? Or do we all have a responsibility to the broader world around us to lessen impacts even when they won't affect us personally?
Shootist
1.4 / 5 (22) Oct 15, 2013
No one lives there, so no one has responsibility to take care of it? Is that the argument then?


Who "takes care of it" when it is struck by a 10km bolide, or when a supervolcano opens up in the depths? Or a Mt. Pico falls into the Atlantic?

VENDItardE
1.3 / 5 (24) Oct 15, 2013
BS
freethinking
1.5 / 5 (26) Oct 15, 2013
I'll believe this when AGW Profit Al Gore sells his monster mansions.
VendicarE
4.3 / 5 (12) Oct 15, 2013
VendiTard (ParkerTard) don't like reality. We weep for him in the final days of his mental disease.
VendicarE
4.3 / 5 (12) Oct 15, 2013
"I'll believe this when AGW Profit Al Gore sells his monster mansions." - FreeTard-o

As a "freethinker", FreeTard-O believes whatever Faux news tells him to believe.

Rush Limbaugh refers to them as "ditto heads".
GuruShabu
1.2 / 5 (21) Oct 15, 2013
They no nothing about the oceans and have skimpy data about the weather and DARE to make such apocalyptical scary predictions...
And lots of people "believe"...
Since the last IPCC report when they had to admit most of their forecasts were way off target and way above actual numbers they started this very aggressive Goebells' style propaganda.
100% BS
VendicarE
4 / 5 (12) Oct 16, 2013
"Since the last IPCC report when they had to admit most of their forecasts were way off " - GuruTardu

The IPCC makes no short term predictions tardieBoy.

That is a job for weather men.

You do know the difference between climate and weather don't you?

If you do then why are you being willfully stupid?

If you don't then let me inform you for the several dosen'th time that you are being stupid.
Neinsense99
2.8 / 5 (20) Oct 16, 2013
I'll believe this when AGW Profit Al Gore sells his monster mansions.

freeofthinking is incapable of an original post.
Neinsense99
2.8 / 5 (20) Oct 16, 2013
They no nothing about the oceans and have skimpy data about the weather and DARE to make such apocalyptical scary predictions...
And lots of people "believe"...
Since the last IPCC report when they had to admit most of their forecasts were way off target and way above actual numbers they started this very aggressive Goebells' style propaganda.
100% BS

You have the gall to dismiss others when the second word in your comment is an error in basic English diction? "No" means 'not yes'. It is not a substitute for the word 'know'.
NikFromNYC
1.5 / 5 (22) Oct 16, 2013
Oceans love "pollution."
The biosphere eats carbon.
The biosphere eats nitrogen.
The biosphere bathes in heat, blissfully.

Everybody knows this.

Biology has had billions of years to pre-adapt to crazy elemental change. Humans are now vastly fertilizing the whole planet by releasing long locked up nutrients.

But you say this isn't so, "scientists"?

Greenpeace and "scientist" friends are the only reason we are stuck with scarce and dangerous old nuclear reactor designs in an era of iPhones and cancer cures.

At the very point in history in which anybody can access historical archives of violent weather in recent centuries to contrast it to our contemporary Eden, the sky is falling?!

Thankfully, NYC has offered up Fox News, tube dress paradise.

A pussified old school religion like Christianity should be shunned?

Why? And why now?

Quantum physics?!

Meditate away, geeks!

How's your organ music project coming along?

Oh, you don't *have* that.

Oh well.
Tony_R
1.6 / 5 (20) Oct 16, 2013
Anyone who still believes anything coming out of the IPCC is doubling down on stupid.
NikFromNYC
1.7 / 5 (23) Oct 16, 2013
There is a serious dent in the air of superiority of Quixotic warmees.

"depletion of dissolved oxygen" = doublespeak for biological abundance.

"Even the seemingly positive changes at high latitudes are not necessary beneficial." = doublespeak admission that overall effect is highly positive.

"This is a growing concern...." = rent seeking panic in a new age of reason and reasoned defunding of junk science. Cue Drug War hysteria and the diabetes-promoting Food Pyramid!

"no corner of the world ocean will be untouched by climate change by 2100." = this has been boringly true each and every decade for 350 years according to actual on the ground real thermometer records:
http://i.minus.com/idAOoE.gif

"assistant professor at the Department of Geography in the College of Social Sciences at the University of Hawai'i" = I rest my case!

-=NikFromNYC=-, Ph.D. in carbon fucking chemistry, bitches (Columbia/Harvard)
GuruShabu
1.4 / 5 (19) Oct 16, 2013
They no nothing about the oceans and have skimpy data about the weather and DARE to make such apocalyptical scary predictions...
And lots of people "believe"...
Since the last IPCC report when they had to admit most of their forecasts were way off target and way above actual numbers they started this very aggressive Goebells' style propaganda.
100% BS

You have the gall to dismiss others when the second word in your comment is an error in basic English diction? "No" means 'not yes'. It is not a substitute for the word 'know'.

Neinsense99, you are arrogant e try to point something that has NOTHING to do with the subject to base your opinion. That's really a big mistake.
English, which is my third language allows sometimes to write as is sounds.
For example: In da house.
Got dat?
Neinsense99
2.5 / 5 (18) Oct 16, 2013
They no nothing about the oceans and have skimpy data about the weather and DARE to make such apocalyptical scary predictions...
And lots of people "believe"...
Since the last IPCC report when they had to admit most of their forecasts were way off target and way above actual numbers they started this very aggressive Goebells' style propaganda.
100% BS

You have the gall to dismiss others when the second word in your comment is an error in basic English diction? "No" means 'not yes'. It is not a substitute for the word 'know'.

Neinsense99, you are arrogant e try to point something that has NOTHING to do with the subject to base your opinion. That's really a big mistake.
English, which is my third language allows sometimes to write as is sounds.
For example: In da house.
Got dat?

Says the one who inserts the comparison to Goebbels....
VendicarE
3.7 / 5 (10) Oct 18, 2013
""depletion of dissolved oxygen" = "doublespeak for biological abundance." - NikkieTard

A condition that kills all oxygen breathing animals is "biological abundance".

Are you off your meds again TardieBoy?

You seem to be a few light bulbs short of a lamp.
VendicarE
3.6 / 5 (9) Oct 18, 2013
"Oceans love "pollution." - NikkieTard

Just as NikkieTard loves to put on his rubber cap and drink how own urine.

90 percent of all large fish are now gone from the oceans.

Republican NikkieTard considers that fact to be an example of "abundance".

By the way TardieBoy. What happened to your PHD in Chemistry?

Have you been making your own illegal pharmaceuticals?

That would explain your deviant behavior.

VendicarE
3.4 / 5 (9) Oct 18, 2013
"Biology has had billions of years to pre-adapt to crazy elemental change." - NikkieTard

Is that why biologists are expecting a 30 percent extinction rate due to warming, by 2100?

Have you suffered from your mental condition all your life? Or did cheap drugs trigger it?
Tom_Andersen
1.6 / 5 (7) Oct 20, 2013
Looking at both sides of the comments here: You have to admit that this report reeks of 'doublespeak', while at the same time we are certainly playing with the atmosphere, which at the very least we know little of the overall consequences.

To say that the IPCC report 5 is anything but a political document is wrong. For example, graphs were removed by government editors that looked damaging to previous 'robust models'. These graphs were eliminated to give governments a way to continue with huge largely unsuccessful (except in vote garnering) programs.

Why anyone places any merit in a report that is edited by governments is crazy.