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TerryM

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Re: Carbon Cycle
« Reply #250 on: October 01, 2015, 01:32:32 AM »
Bruce

In Arctic waters with the inverted thermocline do copepods still go to the bottom to hibernate.

(sorry, my question mark key as well as the apostrophe do not work - sometimes leaves things a little stilted)

Thanks
Terry

Bruce Steele

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Re: Carbon Cycle
« Reply #251 on: October 01, 2015, 03:13:58 PM »
Terry, I don't have a good answer to your question. Copepods are an import part of the plankton in the Arctic with one study reporting copepod populations at 80% of plankton volume. They also appear to be resilient to the effects of ocean acidification.
 The study about their contribution to carbon transport was in the Atlantic and I don't know about their hibernation at depth further north. One Arctic study shows most ,94%,copepods at depth                                ( 300-2000meters)are dead but I would imagine where in the Arctic you look is important , Pacific or Atlantic side? 94% mortality would indicate something other than hibernation going on at least at the site studied.

  http://plankt.oxfordjournals.org/content/early/2013/09/06/plankt.fbt079.full
« Last Edit: October 01, 2015, 03:20:41 PM by Bruce Steele »

TerryM

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Re: Carbon Cycle
« Reply #252 on: October 01, 2015, 10:40:46 PM »
Thanks Bruce
Considering a 94% mortality rate, any attempts of those viable at relocating to whatever thermal strata is most desirable at a particular time of year, or at a particular stage of their life cycle, might be considered a failure.
The inverted thermocline of arctic waters could be confusing to species adapted to diving deeper when heading for cooler regions, (or the opposite), hence huge die offs when advection of Atlantic or Pacific waters into the Arctic changes.
I wonder if the deeply penetrating and mixing waves now prevalent in so many fringe regions could be having an effect on species that evolved to make use of the former more static conditions. If so large die offs of copepods might be an additional exacerbating feedback.
Taking these measurements apparently is something new so it is possible that the 94% figure is nothing unusual & is in fact a common occurrence. ;-)
Terry

solartim27

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Re: Carbon Cycle
« Reply #253 on: October 01, 2015, 11:55:48 PM »
Nice article on Bryozoans off of Antarctica taking up carbon by British Anarctic Survey.

https://www.bas.ac.uk/media-post/press-release-sea-bed-life-captures-carbon/

Less sea-ice stimulates more growth in the algae that feeds the bryozoans, providing longer meal times. The data reveal that the annual production of carbon in the bodies of these bryozoans has increased due to a combination of the animals growing more, living for longer and being more abundant. According to author Dr David Barnes from BAS these animals now take up 75,000 tonnes of carbon more than 20 years ago.

Author David Barnes interviewed on BBC
http://www.bbc.co.uk/programmes/p032sj15
FNORD

Bruce Steele

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Re: Carbon Cycle
« Reply #254 on: October 03, 2015, 04:30:40 AM »
If anyone has time for a bit of a read here is a open access article on the carbon cycle as it relates to the ocean.

http://www.earth-syst-dynam.net/6/327/2015/esd-6-327-2015.html

Bruce Steele

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Re: Carbon Cycle
« Reply #255 on: October 05, 2015, 06:55:25 PM »
Terry, Here is some backup for my claim that copepods can handle acidification fairly well. They can also handle water temperature changes expected over the next 80+ years but apparently starvation is kinda tough on them. Nothing can handle starvation too well however. :-\

http://www.nature.com/articles/srep13690

TerryM

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Re: Carbon Cycle
« Reply #256 on: October 05, 2015, 08:56:05 PM »
Thanks Bruce
If the 11 day difference between hatch time and food availability were the primary reason for the 70% die off I would be watching for a huge jump in the prevalence of their prey species. It seems however that scarcity of prey through their full life cycle is more the problem and that AGW & or acidification is taking its toll even further down the food chain.
Robust little critters, but they still need to be fed.
Terry

AbruptSLR

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Re: Carbon Cycle
« Reply #257 on: October 08, 2015, 06:43:21 PM »
The linked Climate Central article indicates that increasing heat in the oceans is causing a global coral bleaching event this year.  We should all remember that coral is the canary in the coal mine for the oceans, and this high ocean heat content will have serious consequences for other Earth Systems soon enough:

http://www.climatecentral.org/news/hot-oceans-global-coral-bleaching-19528

Extract: "For the past year, the world’s corals have been getting increasingly pummeled by climate change. Now with El Niño kicking ocean heat into overdrive, much of the world’s oceans have turned deadly for the world’s corals.

On Thursday, the National Oceanic and Atmospheric Administration (NOAA) announced a global coral bleaching event. This year joins the ranks of 1997 and 2010 as the only times on record that bleaching has occurred in all three of the world’s oceans that support coral at the same time."
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AbruptSLR

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Re: Carbon Cycle
« Reply #258 on: October 08, 2015, 06:53:17 PM »
As follow-up on my last post, the linked SkS article (see the attached plot) shows that the ocean heat content (from 0 to 2000m depth) has continued to increase through June 2015; which will short activate numerous Earth Systems for more future positive feedback:

http://www.skepticalscience.com/2015-Still-No-Let-Up-in-Ocean-Warming.html

Extract: "Ocean warming has made up 93% of global warming in the last 5 decades (IPCC AR5 Chapter 3) and the first six months of ocean heat data for 2015 are now available from the National Centers for Environmental Information (NCEI). Armed with the knowledge that increasing industrial greenhouse gas emissions trap ever more heat in the atmosphere and ocean, it will come as no surprise whatsoever to learn that the strong ocean heating of recent years has continued into 2015."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Bruce Steele

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Re: Carbon Cycle
« Reply #259 on: October 13, 2015, 08:34:48 PM »
A new meta-analysis of 642 papers results in  " Global marine analysis suggests food chain collapse "
News release:

http://www.adelaide.edu.au/news/news81042.html

From the PNAS paper
 Analysis of responses in short-and longterm experiments and of studies at natural CO2 vents reveals little evidence of acclimation to acidification or temperature change, except for microbes.

http://www.pnas.org/content/early/2015/10/06/1510856112.abstract

My thoughts:
What this analysis doesn't cover is the time frame of the damage done should we proceed with the chemical changes that result in the biological responses and food chain results here described. The time for chemical changes to resolve is in the hundred thousand year timeframe but the time for evolution to restore biodiversity after an extinction event is in the million year timeframe. 
 

Bruce Steele

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Re: Carbon Cycle
« Reply #260 on: October 15, 2015, 07:46:28 PM »
http://www.biogeosciences.net/12/5853/2015/bg-12-5853-2015.pdf


Today I am having my problems. My problems are with the inevitability of acidification over the next 30-50 years here along the California coast. 
From the conclusions of a paper released recently titled , Including high-frequency
variability in coastal ocean acidification projections
" Model projections suggest that anthropogenic ocean acidification will continue to progress in the Calif. Current System and other up-welling margins over the next several decades regardless of any changes in Co2 emissions ; any impacts from reduced emissions will only be observed mid-century and beyond"
 So in very rough numbers the 500 Gt of carbon we emitted so far will be matched by another 500 Gt over the next fifty years . The first 500 Gt has precipitated an acidification event that is already causing biological damage to Pacific Oysters and Pteropod populations. This damage will progress to include several more species with the CO2 already emitted and the 500 GT extra we are on track to emit will then take down hundreds of more species if we don't massively curtain our consumption, end capitalism, crash the world economy or ideally all three.
My problem is the only solutions I believe sufficient are also going to result in massive human economic system collapse and without this rather harsh outcome for my fellow humans we will continue to contribute to an already rather bleak outcome for numerous marine species already baked in for the next 30-50 and getting worse by the day.
 This is a message that will never be delivered and the few people who understand the ramifications have no idea how to respond. 
 In my state there are fewer than a handful of fishermen fluent in the problem, there have been zero government or private meetings that are designed to inform fishermen as to the inevitable downsides to the fish stocks or economics of their respective fisheries. I have been banging the drum for a decade now and other than radicalizing my presentation and bleak delivery I haven't gotten anywhere.
Neither has the situation improved for the species on a trajectory with doom.
Just another paper and a bad start to an otherwise beautiful day. I gotta go work until I burn some steam physically cause my intellectual forays are a waste of everyones time I guess.

TerryM

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Re: Carbon Cycle
« Reply #261 on: October 17, 2015, 07:04:12 PM »
Bruce

Hope it doesn't sound too ghoulish, but if a species is definitely destined for extinction within a very short time period, why not harvest them all, put a few in aquariums, like a seed bank, & eat the rest, (assuming they are tasty ;>)

This preemptive grave robbing might take pressure off other species that are projected to be decimated, but not to be eliminated.

Re. your flood concerns in another thread:
I'd come across some research showing that California has warmed so much that large mountain snowpacks could be a thing of the past, regardless of El Nino precipitation. They assume rain instead of snow. Bad news for the continuing drought, but possibly good news for those concerned about spring flooding. Alas, my computer crashed & I cant find the link again, but it is out there somewhere.

O.T.
Wondered if your hirsute, smitten, VW driving, porcine companion has a name. Was thinking of Harry (or Harriet), alternatively, Wooliam or Woolma, & possibly, if religiously inclined, Esau or Esauma?

Terry

Bruce Steele

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Re: Carbon Cycle
« Reply #262 on: October 18, 2015, 04:44:52 AM »
TerryM,  I can't answer both halves of your query without a bit of levity. If that is your intent ,thank you.
 Re. Accepting extinction
If you were to pick a species that was  first to become locally extinct in the wild, Pacific Oysters might be a likely choice. George Walbusser in the webinar I recently hosted showed that the window of opportunity for recruitment is narrowing as the combination of temperature and acidification reduce the number of days where oyster larva can successfully develop through the first and critical week of their development. The Washington and Oregon coasts where this narrowing window of recruitment opportunity will continue to restrict successful recruitment isn't however native habitat for this species. In japan and Asia where this species is native it will be decades before these oysters suffer similar problems. Southern Calif. is another area where Pacific Oysters are now recruiting in the wild and the water conditions in S.C. will also remain favorable for decades after the Northwest Coast is no longer viable habitat for this species. in the long term Southern Calif. will follow the Northwest Coast before Japan and Asia do. In all these areas aquacultured Oysters grown in controlled conditions for their larval life stages  will still grow to maturity once past that critical stage of development.
 There are wild stocks of shellfish that do not have the aquaculture industry to help them however. For  stocks like pteropods human intervention isn't an option and they will become locally extinct as water conditions continue to deteriorate . They will not become extinct as a species until all of their range is too corrosive for their survival. Because pteropods are a major part of some fish species diets their local demise will cascade up through the food chain. These changes will likely have large impacts on major fisheries along the West Coast of North America. There may be similar forage fish problems in other upwelling systems like the Humboldt Current in similar timeframes. Again these problems will not likely respond to manipulation like aquacultured Oysters.
 So extinction is a local problem before it becomes a problem across the whole of a species range.

Pigs are the funny part of your post. Domestic pigs are largely a product of human intervention in their genes. For centuries after the ocean has entered it's full blown extinction event pigs will still be a major part of  the human diet. Human intervention in marine species genes  is a much more contracted in time and humans haven't manipulated genetic selection in marine mammals . Therefor any concept like affection from marine species is likely anthropomorphism. Pigs , dogs and other products of thousands of years of selective breeding may actually like us.
We tend to select for that. Seafood not so much.
 I really need smaller pigs to make my V.W a good joke. Petunia is just getting too big. She still might make a good truffle hunting hog however.

For Sierra snowpack you might be thinking of this
http://www.skepticalscience.com/global-warming-shrinking-california-snowpack.html
For Sierra snowpack you might be thinking of this           
« Last Edit: October 18, 2015, 06:22:02 AM by Bruce Steele »

AbruptSLR

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Re: Carbon Cycle
« Reply #263 on: November 09, 2015, 08:19:59 PM »
The linked (open access) reference discusses the complex factors affecting the lifetime of methane in the atmosphere over the past 40 years.  The attached plot shows that after a period of declining lifetime, since 2010 methane's lifetime has been increasing again:


Dalsøren, S. B., Myhre, C. L., Myhre, G., Gomez-Pelaez, A. J., Søvde, O. A., Isaksen, I. S. A., Weiss, R. F., and Harth, C. M.: Atmospheric methane evolution the last 40 years, Atmos. Chem. Phys. Discuss., 15, 30895-30957, doi:10.5194/acpd-15-30895-2015, 2015.

http://www.atmos-chem-phys-discuss.net/15/30895/2015/acpd-15-30895-2015.html

http://www.atmos-chem-phys-discuss.net/15/30895/2015/acpd-15-30895-2015.pdf

Abstract: "Observations at surface sites show an increase in global mean surface methane (CH4) of about 180 parts per billion (ppb) (above 10 %) over the period 1984–2012. Over this period there are large fluctuations in the annual growth rate. In this work, we investigate the atmospheric CH4 evolution over the period 1970–2012 with the Oslo CTM3 global Chemical Transport Model (CTM) in a bottom-up approach. We thoroughly assess data from surface measurement sites in international networks and select a subset suited for comparisons with the output from the CTM. We compare model results and observations to understand causes both for long-term trends and short-term variations. Employing the Oslo CTM3 model we are able to reproduce the seasonal and year to year variations and shifts between years with consecutive growth and stagnation, both at global and regional scales. The overall CH4 trend over the period is reproduced, but for some periods the model fails to reproduce the strength of the growth. The observed growth after 2006 is overestimated by the model in all regions. This seems to be explained by a too strong increase in anthropogenic emissions in Asia, having global impact. Our findings confirm other studies questioning the timing or strength of the emission changes in Asia in the EDGAR v4.2 emission inventory over the last decades. The evolution of CH4 is not only controlled by changes in sources, but also by changes in the chemical loss in the atmosphere and soil uptake. We model a large growth in atmospheric oxidation capacity over the period 1970–2012. In our simulations, the CH4 lifetime decreases by more than 8 % from 1970 to 2012, a significant shortening of the residence time of this important greenhouse gas. This results in substantial growth in the chemical CH4 loss (relative to its burden) and dampens the CH4 growth. The change in atmospheric oxidation capacity is driven by complex interactions between a number of chemical components and meteorological factors. In our analysis, we are able to detach the key factors and provide simple prognostic equations for the relations between these and the atmospheric CH4 lifetime."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Bruce Steele

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Re: Carbon Cycle
« Reply #264 on: November 11, 2015, 04:35:48 PM »
I have posted here on the vulnerability of Red King Crab larva to near term acidification in Alaska.
Most of the work on adaptation for fisheries has focused on Pacific Oysters , an aquacultured species.
I worry that wild fisheries will be left in the lurch without similar lab cultured work on wild stocks.
The following link shows Alaskan researchers making the first out plants of lab raised Red King Crab.
They state several reasons for their work but acidification is one of them.

http://www.nmfs.noaa.gov/stories/2014/01/01_06_14long_live_the_king.html

Bruce Steele

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Re: Carbon Cycle
« Reply #265 on: November 11, 2015, 04:50:02 PM »
Tanner Crab is another species sensitive to near term acidification although less so than Red King Crab. A new economic analysis shows "Catch & profits would be expected to decrease by 50% in 20 years if natural mortality is affected by ocean acidification" .  Punt et al 2015.  See below

http://icesjms.oxfordjournals.org/content/early/2015/11/06/icesjms.fsv205

Bruce Steele

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Re: Carbon Cycle
« Reply #266 on: November 15, 2015, 08:13:00 PM »
There is a very good article over at Skeptical Science on ocean acidification by Rob Painting. It is focused on why a rapid rise in atmospheric Co2 results in a reduction in available carbonate and an increase in bicarbonate. With a rapid increase in Co2 carbonate can be reduced to levels where it becomes undersaturated and the shells of certain shellfish begin to dissolve. This is already happening in parts of the
California Current in nearshore areas annually dominated by upwelling.
 The article also explains why in past eras with high levels of atmospheric Co2 shellfish could still thrive. The rate of change in Co2 is the important factor because with a slow rate of change the natural weathering of terrestrial carbonates and silicates can maintain levels of alkalinity in the oceans sufficient to maintain supersaturation of carbonates. The article also talks to the unique nature of the current situation and the unprecedented rapidity of the current rise of Co2.
     Wili ( I think the same Wili that posts here ) asks why 300 million years is used as a limit to the records of past extinction events tied to acidification. I believe the reason is the lack of geological material still extant from earlier eras. Tectonics have recycled most of the crust from earlier times. If someone here has other ideas I would be interested to hear their thoughts.    

http://www.skepticalscience.com/Why-were-the-ancient-oceans-favorable-to-marine-life-when-atmospheric-carbon-dioxide-was-higher-than-today.html

Bruce Steele

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Re: Carbon Cycle
« Reply #267 on: November 29, 2015, 04:29:23 PM »
As the amount of Anthropogenic Co2 has increased  the atmospheric, terrestrial and oceanic percentages of the CO2 sinks have remained constant. This is a good thing because if either the terrestrial or oceanic sinks begin to fail the atmospheric portion will as a result rise at a faster pace than the current rate. It appears an increase in the population of coccoliths in the Atlantic , a tenfold increase from 1965, is at least partially responsible for the increasing efficiency of the oceanic sink.
 Although we humans are benefiting from this population increase in coccoliths there is likely an inflection point sometime in the future where the rising level of acidification will reverse this trend.
Coccoliths, like many other calcifying phytoplankton, dissolve when CO2 builds to a point where undersaturation results. For now the coccoliths are working to our benefit but when they and other calcifying phytoplankton begin to fail so to shall part of the oceanic carbon sink. If we cross this rather critical chemical rubicon it will be many tens of thousands of years before the current 25% ocean
25% terrestrial and 50% atmosphere portions of the carbon cycle are restored.

    http://www.sciencemag.org/content/early/2015/11/24/science.aaa8026

http://phys.org/news/2015-11-rapid-plankton-growth-ocean-carbon.html

Bruce Steele

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Re: Carbon Cycle
« Reply #268 on: December 02, 2015, 05:18:49 PM »
From a fishermen's perspective a list of species vulnerable to increased ocean acidification is an important list. That list isn't very big at this point but it contains some extremely important species from an economic standpoint. Red King Crab, Tanner Crab, and Pacific Oysters are all on the list and Pteropods are on it as a very sensitive prey species.
 "    Ocean acidification, a decrease in ocean pH due to absorption of anthropogenic atmospheric CO2, has variable effects on different species. To examine the effects of long-term exposure on Tanner crab (Chionoecetes bairdi) embryonic development, hatching success, and calcification, ovigerous females were reared in one of three treatments: ambient pH (∼8.1), pH 7.8, and pH 7.5 for 2 years. Embryos and larvae in year 1 were from oocytes developed in the field and appear resilient to high pCO2. Embryos and larvae in year 2 were from oocytes developed under high pCO2 conditions. Oocyte development appears sensitive to high pCO2, effects carryover and altered embryonic development, and reduced hatching success with on average 71% fewer viable larvae hatched in the pH 7.5 treatment than in the other treatments. Per cent calcium was reduced among females exposed to pH 7.5 waters, and their carapaces were noticeably more pliable than those in the other treatments. Softer carapaces may result in reduced defences against predators, and a reduction in the ability to feed on prey with hard parts such as shells. The results from this long-term study suggest that projected ocean pH levels within the next two centuries will likely have a pronounced impact on Tanner crab populations unless the crab are able to acclimatize or adapt to changing conditions.


Swiney K. M., Long W. C. & Foy R. J., in press. Effects of high pCO2 on Tanner crab reproduction and early life history—Part I: long-term exposure reduces hatching success and female calcification, and alters embryonic development. ICES Journal of Marine Science. Article (subscription required)

http://news-oceanacidification-icc.org/2015/12/02/effects-of-high-pco2-on-tanner-crab-reproduction-and-early-life-history-part-i-long-term-exposure-reduces-hatching-success-and-female-calcification-and-alters-embryonic-development/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+wordpress%2FlRgb+%28Ocean+acidification%29


Bruce Steele

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Re: Carbon Cycle
« Reply #269 on: December 17, 2015, 07:00:45 PM »
Domoic acid is a neurotoxin produced by a diatom ( Pseudo-Nitzchia ) that bioaccumulates in fish and shellfish. There has been a large event this year along the Calif. Coast, health warnings  go out with
when TA reaches 20ppm and some seafood samples have reached 1000ppm, triggering crab and coastal pelagic fishing closures.

A paper written by Dave Hutchins showed that high dissolved Co2 and phosphorus limited conditions caused Domoic acid to increase by a factor of four. The level of pCO2 that caused this DA spike was
700 ppm in the lab and the level of pCO2 measured at a buoy off Santa Barbara reached 650ppm in April this year just as the first DA warnings were being issued.

  http://mooring.ucsd.edu/projects/cce/data/img_old/cce2_01_xco2_999.png

Large plankton blooms in upwelling regions tend to draw down phosphorus levels as the bloom matures. I don't have numbers on the phosphorus levels that accompanied this DA event but a large plankton bloom may have caused phosphorus limited conditions.

http://www.aslo.org/lo/toc/vol_56/issue_3/0829.html

I fixed the bad link to the Article( open access  PDF ) In reviewing it I also realized that phosphorus limitation resulted in a thirty fold increase with high pCO2 contribution a four fold increase at 730 ppm
 

Domoic acid can also present trouble for birds and mammals as was recently pointed out by Laurent.
« Last Edit: December 18, 2015, 12:40:43 PM by Bruce Steele »

AbruptSLR

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Re: Carbon Cycle
« Reply #270 on: January 11, 2016, 11:56:12 PM »
The linked article offers a nice (accessible) summary of the ocean acidification problem, and concludes that geoengineering offers no solution for this crisis:

http://www.huffingtonpost.com/pierce-nahigyan/ocean-acidification-is-ba_b_8952240.html

Extract: "The ocean absorbs about 30 percent of the CO2 emitted from human activites. As the volume of atmospheric CO2 grows, the ocean collects its proportionate share. To give you an idea of how much that is, in 2013, countries emitted nearly 40 billion tons of carbon. According to the World Meteorological Organization, that represents the biggest surge in CO2 concentration since 1984.

That's bad news for the climate, but it's really bad news for the ocean. When the ocean absorbs CO2, it converts the gas into carbonic acid. Until the Industrial Revolution, there wasn't enough carbonic acid in the water to unbalance the ecosystem. But after more than a century of unchecked carbon emissions, the ecosystem has been measurably upended. The pH level of surface waters has dropped from 8.18 to 8.07, which is the lowest its been in the last 300 million years.

So what does more acid in the ocean mean? For one thing, it means less calcium carbonate. This mineral is a key ingredient in the shells of several marine species, and without it, fewer shellfish are surviving to adulthood. One oyster farm in Washington state reported that their oyster production declined by 42 percent in just 10 years. The tiny shellfish that feed Alaska's salmon stocks are also in danger, to say nothing of the state's lucrative crab fishery.

Carbonic acid not only dissolves calcium carbonate, it also dissolves limestone, which makes it more difficult for coral to grow. Combine that with the reduction of pteropods and other zooplankton at the bottom of the food chain and the impacts to marine life are potentially catastrophic.

Life above sea level will also be impacted. Investigations of carbon upwelling zones along the West Coast suggest that lower pH levels make it more difficult for certain phytoplankton to absorb nutrients, rendering them vulnerable to disease and toxins. And that's a problem, because healthy phytoplankton produce about 60 percent of the oxygen on Earth.

Some diatoms, like Pseudo-nitzschia, actually produce more toxin at lower pH levels. According to Dr. Vera Trainer, an oceanographer with NOAA's Fisheries Marine Biotoxins Program, ingesting toxins from Pseudo-nitzschia can cause permanent short-term memory loss and in some cases death. Studies have shown that this species of phytoplankton can be five times more toxic at levels of ocean acidification already occurring off the California coast. NOAA suspects that a string of bird and whale deaths in 2015 may be due to domoic acid poisoning, a byproduct of these toxic algae blooms.

...

When we take a step back, the bleak picture we've painted here comes into focus. The ocean is acidifying, making it less hospitable to marine life and less profitable to coastal economies; as it acidifies, some phytoplankton make less oxygen and others become more poisonous; as they become more poisonous, they contaminate our water and kill more fish. And while this is going on, ocean warming is just making it all worse.

Unfortunately, that's not the bad news. The bad news is, it could take a millennium for the ocean to recover from what we've done to it. Humanity does not have the power to reverse this crisis. In the best case scenario (i.e., we stop burning fossil fuels), it can only be prevented from getting worse."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Bruce Steele

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Re: Carbon Cycle
« Reply #271 on: January 16, 2016, 07:36:18 AM »
I once read a science piece on the effects of decreasing pH on  developing sea urchin larva. It's been about ten years since I saw that first evidence of changing atmospheric  Co2 levels and how it might impact the ocean and the sea urchins that provided me with a living. The oyster story came after the 2004 Shiryama  paper that caught my attention. Within two years the oyster hatcheries began to experience difficulties. I always thought using industry , aquaculture and wild fisheries , was a way to draw a focus on the problems of acidification. Much of the interest at a Congressional level, bipartisan interest, interest that can potentially drive legislation centers on industry and commercial interests.
The aquaculture oyster industry has very much contributed to educating the public and the halls of Congress. The full education on acidification and it's potential impacts goes far far beyond money interest of course but getting the public or legislators to understand what might happen if a little creature like a peteropod begins to fail. That is a challenge.
 The biological carbon pump may be damaged , it may already be starting in some places. Like the post ASLR put up says it will take a very long time to repair should we ignore each milestone, each new species whose individual members  no longer thrive. Shells that don't rain into the depths.
Tiny lives so easily ignored. First only in a few places in that great sea, then bigger areas, and the carbon that would rain down dwindles. The carbon pump falters. There is the story that counts , there is so much we don't know , but a great many people need to understand and care. It is a very sad story and it is difficult to get people to understand. 
 
So from an article written by a group of scientists looking back over the last ten years of evidence and trying to pick parts of the story to illustrate the larger risks I will quote some extracts.

     "Impaired shell production will reduce the strength of the biological carbon pump because less carbonate ballast will be produced in the upper regions of the water column ( Bednarsek  et al 2014 ).   Pteropods are responsible for an estimated 
20%-42% of the total carbonate production in the ocean ( Bednarsek et al 2012 )
so carbon pump effects may be large. At saturation states projected to occur in the northeastern Pacific by 2050 at a depth of 100 m, the flux of biological removal may be halved ( Bednarsek et al 2014 )
 This reduction in the carbon pump could potentially create a positive feedback that reduces the rate of biological removal of carbon from the upper atmosphere under conditions of intensifying carbon enrichment from anthropogenic sources. "

  http://bioscience.oxfordjournals.org/content/66/1/14.abstract

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Re: Carbon Cycle
« Reply #272 on: January 16, 2016, 08:15:21 AM »
Since I misspelled Shirayama and forgot to include the lead author , Kurihara I should at least include a link. Here is what ocean acidification looked like in 2004. Kurihara and Shirayama 2004

http://www.int-res.com/articles/meps2004/274/m274p161.pdf


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Re: Carbon Cycle
« Reply #273 on: January 20, 2016, 04:16:06 PM »
The linked article indicates that due to climate change related warming of the Indian Ocean, the mixing of the surface, and nutrient-rich deep, waters has decreased resulting in about a 20% reduction in phytoplankton.  While the article focuses on the impacts of this on seafood, it also means a reduction of a negative feedback, which will result in accelerating global warming in the future:

http://www.reuters.com/article/sri-lanka-fishing-climatechange-idUSKCN0UX0IQ

Extract: ""Rapid warming in the Indian Ocean is playing an important role in reducing phytoplankton up to 20 percent," said Roxy Mathew Koll, a scientist at the Centre for Climate Change Research at the Indian Institute of Tropical Meteorology in Pune.
Over six decades, rising water temperatures appear to have been reducing the amount of phytoplankton – microscopic plants at the base of the ocean food chain – available as food for fish, according to research released in December by Koll and other scientists from the United States, South Africa and France.
That “may cascade through the food chain, potentially turning this biologically productive region into an ecological desert,” Koll said. Such a change would curb food security not only in Indian Ocean rim countries but also global fish markets that buy from the region, he said.
As waters in parts of the Indian Ocean have warmed by 1.2 degrees Celsius over the last century, the mixing of surface water and nutrient-rich deeper waters have slowed, the scientists said. That has prevented nutrients from reaching the plankton, which are mostly active in surface waters."

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Re: Carbon Cycle
« Reply #274 on: January 21, 2016, 01:37:32 AM »
The linked article indicates that sediments of river-dominated ocean margins (RiOMars) represent accumulation centers for Corg and that microbial metal reduction in Corg remineralization due to dissimilatory Fe(III) reduction may be more significant than previously thought in continental slope sediments.  This could mean that carbon cycling in the marine environment could serve as a positive feedback to emit CO₂ into the atmosphere at a rate faster than previously considered:

Jordon S. Beckler, Nicole Kiriazis, Christophe Rabouille, Frank J. Stewart & Martial Taillefert (20 January 2016), "Importance of microbial iron reduction in deep sediments of river-dominated continental-margins", Marine Chemistry, Volume 178, Pages 22–34

doi:10.1016/j.marchem.2015.12.003


http://www.sciencedirect.com/science/article/pii/S0304420315300633

Abstract: "Remineralization of organic carbon in deep-sea sediments is thought to proceed primarily via aerobic respiration and sulfate reduction because the supply of nitrate and metal oxides is not usually significant in deep-sea sediments. Dissimilatory metal reduction, on the other hand, may represent a dominant pathway in coastal and continental shelf sediments where delivery of terrigenous Fe(III) and Mn(IV/III) oxides is sufficiently high or where physical mixing processes near the sediment–water interface can result in the reoxidation of Fe2 + or Mn2 +. Passive continental margin sediments receiving outflow from large rivers are well-known deposition centers for organic carbon and may also be hotspots for metal-reducing microbial activity, considering the simultaneous rapid deposition of unconsolidated metal oxides of terrigenous origin. Despite its potential, only a few studies have examined the role of microbial metal reduction in Corg remineralization in these environments. To investigate carbon remineralization processes in continental margin sediments, shallow cores across channels and levees in the Congo River fan (~ 5000 m) and Louisiana slope (< 1800 m) were profiled for the main redox species involved in early diagenesis using a combination of voltammetric gold mercury (Au/Hg) microelectrodes and conventional analyses. Interestingly, metal reduction dominated carbon remineralization processes in the top ~ 20 cm of sediment subject to high deposition, while evidence for sulfate reduction was lacking. These findings suggest that dissimilatory Fe(III) reduction may be more significant than previously thought in continental slope sediments, which may have important implications on carbon cycling in marine environments. In addition, these findings may have geological implications in controlling atmospheric oxygen levels over geological time and the evolution of microbial life on Earth."
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Re: Carbon Cycle
« Reply #275 on: January 27, 2016, 08:25:26 PM »
." Our results suggest that reduced respiration lead to increased net carbon fixation at high CO2. However, the increased primary production did not translate into increased carbon export, and did consequently not work as a negative feedback mechanism for increasing atmospheric CO2 concentration."

http://www.biogeosciences-discuss.net/bg-2015-608/

More evidence acidification may impair the carbon pump.

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Re: Carbon Cycle
« Reply #276 on: February 07, 2016, 07:40:33 PM »
From the same Mesocosm studies in the Baltic Sea that the above posted link was based upon. A shift in the microbial community.
"Overall our results point to a shift towards a more regenerative system with potentially increased productivity but reduced carbon export."

 http://www.biogeosciences-discuss.net/bg-2015-606/bg-2015-606.pdf


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Re: Carbon Cycle
« Reply #277 on: February 12, 2016, 11:24:07 PM »
The linked article indicates that for the past ten years the North Atlantic has been absorbing 50% more CO₂ than during the previous ten years.  Thus we are performing a one short experiment of the impact of accelerating ocean acidity on marine life:

http://climatenewsnetwork.net/north-atlantic-doubles-carbon-intake/?utm_source=Climate+News+Network&utm_campaign=6687b69c4e-North+Atlantic+doubles+carbon+intake&utm_medium=email&utm_term=0_1198ea8936-6687b69c4e-38798465&mc_cid=6687b69c4e&mc_eid=441cf4f801

Extract: "The North Atlantic Ocean is responding rapidly to climate change: it has absorbed 50% more carbon from human activities in the last 10 years, than in the previous decade, a new study shows.



The extra CO2 absorbed means a change in ocean chemistry: the oceans are becoming increasingly acidic at an unprecedented rate, with unknown consequences for corals, shellfish and juvenile fish."
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Re: Carbon Cycle
« Reply #278 on: February 23, 2016, 07:36:26 PM »
The linked reference indicates that the coral in the Great Barrier Reef will sustain more damage from ocean acidification than previously realized in AR5:

Mathieu Mongin, Mark E. Baird, Bronte Tilbrook, Richard J. Matear, Andrew Lenton, Mike Herzfeld, Karen Wild-Allen, Jenny Skerratt, Nugzar Margvelashvili, Barbara J. Robson, Carlos M. Duarte, Malin S. M. Gustafsson, Peter J. Ralph & Andrew D. L. Steven (2016), "The exposure of the Great Barrier Reef to ocean acidification", Nature Communications, Volume: 7, Article number: 10732, doi:10.1038/ncomms10732

http://www.nature.com/ncomms/2016/160223/ncomms10732/full/ncomms10732.html

Abstract: "The Great Barrier Reef (GBR) is founded on reef-building corals. Corals build their exoskeleton with aragonite, but ocean acidification is lowering the aragonite saturation state of seawater (Ωa). The downscaling of ocean acidification projections from global to GBR scales requires the set of regional drivers controlling Ωa to be resolved. Here we use a regional coupled circulation–biogeochemical model and observations to estimate the Ωa experienced by the 3,581 reefs of the GBR, and to apportion the contributions of the hydrological cycle, regional hydrodynamics and metabolism on Ωa variability. We find more detail, and a greater range (1.43), than previously compiled coarse maps of Ωa of the region (0.4), or in observations (1.0). Most of the variability in Ωa is due to processes upstream of the reef in question. As a result, future decline in Ωa is likely to be steeper on the GBR than currently projected by the IPCC assessment report."
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Re: Carbon Cycle
« Reply #279 on: February 24, 2016, 07:06:11 PM »
Both of the linked articles discuss our on-going "longest-global-coral-bleaching" event ever observed; which is likely due to a combination of on-going global warming and the impact of the near-El Nino 2014 event combined with the Super El Nino 2015-16 event:

http://www.climatecentral.org/news/longest-global-coral-bleaching-20062


http://robertscribbler.com/2016/02/23/human-hothouse-sets-off-longest-coral-die-off-on-record/

Extract: "The big coral die-off began in the Western Pacific as a massive ocean temperature spike built up during 2014. Back then, ocean heat accumulation had hit a very high ramp. A vicious, century-and-a-half long increase in atmospheric greenhouse gasses re-radiated greater and greater portions of the sun’s energy hitting the Earth — transferring the bulk (about 90 percent) to the world ocean system."

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Re: Carbon Cycle
« Reply #281 on: March 17, 2016, 03:31:44 PM »
" Simulations with a modified version of the Long-term Ocean-atmosphere-Sediment CArbon cycle Reservoir model, which includes a fully coupled carbon-calcium cycle, indicate that increased weathering rates and ocean acidification (potentially caused by Siberian Trap volcanism) are not capable of producing trends observed in the record, as previously claimed. Our model results suggest that combined effects of carbon input via Siberian Trap volcanism (12,000 Pg C), the cessation of biological carbon export, and variable calcium isotope fractionation (due to a change in the seawater carbonate ion concentration) represents a more plausible scenario. This scenario successfully reconciles δ13C and δ44Ca trends observed in the sediment record, as well as the proposed warming of >6°C."
 
This article includes " the cessation of biological carbon export " in achieving the carbon excursion documented by the sediment record for the largest extinction event in the history of earth.

http://onlinelibrary.wiley.com/doi/10.1002/2015PA002834/abstract;jsessionid=CFEA9879A89D177F6B001267074A461F.f03t04

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Re: Carbon Cycle
« Reply #282 on: March 17, 2016, 03:50:05 PM »
Although the 5,000 Gt carbon used in this simulation is less than half( 12,000 ) that used to drive the
Model used in the end Permian event( see last post ) the speed of the current CO2 anthropogenic release is much faster. Terrestrial weathering and deep sea calcium export and sedimentation can't keep up with the speed of the current event and the processes that regulate ocean pH . Only on a scale of tens of thousands of years do these processes modify the effects of current rates of anthropogenic CO2 inputs.

   http://news-oceanacidification-icc.org/2016/03/02/simulated-effect-of-deep-sea-sedimentation-and-terrestrial-weathering-on-projections-of-ocean-acidification/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+wordpress%2FlRgb+%28Ocean+acidification%29
« Last Edit: March 17, 2016, 04:26:59 PM by Bruce Steele »

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Re: Carbon Cycle
« Reply #283 on: March 17, 2016, 04:23:54 PM »
This study investigates the effects of potential CO2 fertilization upon phytoplankton in mitigating future atmospheric levels as well as future ocean pH. If extra CO2 stimulates bioproductivity and the carbon pump how does that impact future atmospheric and oceanic conditions? At least two recent mesocosym studies have shown carbon export and the carbon pump are negatively rather than positively effected under future BAU CO2 emissions so depending upon CO2 fertilization to continue far into the future is questionable but this study does address to what degree we are dependent upon continued increasing  efficiency of the biological carbon pump. It should also be pointed out that the failure of the carbon pump may be responsible for some part of the carbon excursion experienced during the end Permian event ( see the Komar and Zeebe article in earlier posting #281)

   " It is also found that the effect of CO2-calcification feedback on ocean carbon uptake is comparable and could be much larger than the effect from CO2-induced warming. Our results highlight the potentially important role CO2-calcification feedback plays in ocean carbon cycle and projections of future atmospheric CO2 concentrations."

http://www.nature.com/articles/srep20284
« Last Edit: March 17, 2016, 04:33:33 PM by Bruce Steele »

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Re: Carbon Cycle
« Reply #284 on: April 01, 2016, 06:51:54 PM »
The linked reference discusses how drainage of groundwater is turning grasslands on peat from a carbon sink into a carbon source:

Bärbel Tiemeyer, Elisa Albiac Borraz, Jürgen Augustin, Michel Bechtold, Sascha Beetz, Colja Beyer, Matthias Drösler, Martin Ebli, Tim Eickenscheidt, Sabine Fiedler, Christoph Förster, Annette Freibauer, Michael Giebels, Stephan Glatzel, Jan Heinichen, Mathias Hoffmann, Heinrich Höper, Gerald Jurasinski, Katharina Leiber-Sauheitl, Mandy Peichl-Brak, Niko Roßkopf, Michael Sommer & Jutta Zeitz (31 March 2016),  "High emissions of greenhouse gases from grasslands on peat and other organic soils", Global Change Biology,  DOI: 10.1111/gcb.13303


http://onlinelibrary.wiley.com/doi/10.1111/gcb.13303/abstract

Abstract: "Drainage has turned peatlands from a carbon sink into one of the world's largest greenhouse gas (GHG) sources from cultivated soils. We analyzed a unique data set (12 peatlands, 48 sites and 122 annual budgets) of mainly unpublished GHG emissions from grasslands on bog and fen peat as well as other soils rich in soil organic carbon (SOC) in Germany. Emissions and environmental variables were measured with identical methods. Site-averaged GHG budgets were surprisingly variable (29.2 ± 17.4 t CO2-eq. ha−1 yr−1) and partially higher than all published data and the IPCC default emission factors for GHG inventories. Generally, CO2 (27.7 ± 17.3 t CO2 ha−1 yr−1) dominated the GHG budget. Nitrous oxide (2.3 ± 2.4 kg N2O-N ha−1 yr−1) and methane emissions (30.8 ± 69.8 kg CH4-C ha−1 yr−1) were lower than expected except for CH4 emissions from nutrient-poor acidic sites. At single peatlands, CO2 emissions clearly increased with deeper mean water table depth (WTD), but there was no general dependency of CO2 on WTD for the complete data set. Thus, regionalisation of CO2 emissions by WTD only will remain uncertain. WTD dynamics explained some of the differences between peatlands as sites which became very dry during summer showed lower emissions. We introduced the aerated nitrogen stock (Nair) as a variable combining soil nitrogen stocks with WTD. CO2 increased with Nair across peatlands. Soils with comparatively low SOC concentrations showed as high CO2 emissions as true peat soils because Nair was similar. N2O emissions were controlled by the WTD dynamics and the nitrogen content of the topsoil. CH4 emissions can be well described by WTD and ponding duration during summer. Our results can help both to improve GHG emission reporting and to prioritize and plan emission reduction measures for peat and similar soils at different scales."
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Re: Carbon Cycle
« Reply #285 on: April 06, 2016, 11:54:35 PM »
The linked reference discusses that gross primary production controls the subsequent winter CO₂ exchange in boreal peatlands:

Junbin Zhao, Matthias Peichl, Mats Öquist & Mats B. Nilsson (2 April 2016), "Gross primary production controls the subsequent winter CO2 exchange in a boreal peatland", Global Change Biology, DOI: 10.1111/gcb.13308


http://onlinelibrary.wiley.com/doi/10.1111/gcb.13308/abstract


Abstract: "In high latitude regions, carbon dioxide (CO2) emissions during the winter represent an important component of the annual ecosystem carbon budget; however, the mechanisms that control the winter CO2 emissions are currently not well understood. It has been suggested that substrate availability from soil labile carbon pools is a main driver of winter CO2 emissions. In ecosystems that are dominated by annual herbaceous plants, much of the biomass produced during the summer is likely to contribute to the soil labile carbon pool through litter fall and root senescence in the autumn. Thus, the summer carbon uptake in the ecosystem may have a significant influence on the subsequent winter CO2 emissions. To test this hypothesis, we conducted a plot-scale shading experiment in a boreal peatland to reduce the gross primary production (GPP) during the growing season. At the growing season peak, vascular plant biomass in the shaded plots was half that in the control plots. During the subsequent winter, the mean CO2 emission rates were 21% lower in the shaded plots than in the control plots. In addition, long-term (2001-2012) eddy covariance data from the same site showed a strong correlation between the GPP (particularly the late summer and autumn GPP) and the subsequent winter net ecosystem CO2 exchange (NEE). In contrast, abiotic factors during the winter could not explain the inter-annual variation in the cumulative winter NEE. Our study demonstrates the presence of a cross-seasonal link between the growing season biotic processes and winter CO2 emissions, which has important implications for predicting winter CO2 emission dynamics in response to future climate change."
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Re: Carbon Cycle
« Reply #286 on: April 08, 2016, 04:27:13 PM »
The linked reference presents observational findings that boreal forests can turn from a carbon sink into a carbon source in a short period of time (less than two decades):

David Hadden & Achim Grelle (15 June 2016), "Changing temperature response of respiration turns boreal forest from carbon sink into carbon source", Agricultural and Forest Meteorology, Volume 223, Pages 30–38, doi:10.1016/j.agrformet.2016.03.020


http://www.sciencedirect.com/science/article/pii/S0168192316302131


Abstract: "Seventeen years (1997–2013) of carbon dioxide (CO2) fluxes were measured in a boreal forest stand in northern Sweden using the eddy covariance technique. During the measurement period the forest turned from a net carbon sink into a net carbon source. The net ecosystem exchange (NEE) was separated using values from periods of darkness into the gross components of total ecosystem respiration (TER) and gross primary productivity (GPP), which was calculated as GPP = −NEE + TER. From the gross components we could determine that an increase in TER during the autumn (September to end of November) and spring (March to end of May) periods resulted in the forest becoming a net source of CO2. We observed no increase in the GPP from the eddy covariance measurements. This was further supported by measurements of tree growth rings. The increased TER was attributed to a change in the forest’s temperature response at lower temperatures (−5 to 10 °C) rather than to a temperature increase. This study shows that changes in ecosystem functioning can have a larger impact on the carbon balance than climate warming per se."
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Re: Carbon Cycle
« Reply #287 on: April 08, 2016, 04:31:24 PM »
The linked reference cites an overlooked tropical oceanic CO₂ sink:

J. Severino P. Ibánhez, Moacyr Araujo & Nathalie Lefèvre (5 April 2016), "The overlooked tropical oceanic CO2 sink", Geophysical Research Letters, DOI: 10.1002/2016GL068020


http://onlinelibrary.wiley.com/doi/10.1002/2016GL068020/abstract


Abstract: "The intense rainfall in the tropical Atlantic spatially overlaps with the spread of the Amazon plume. Based on remote-sensed sea surface salinity and rainfall, we removed the contribution of rainfall to the apparent Amazon plume area, thus refining the quantification of its extension (0.84 ± 0.06 106 to 0.89 ± 0.06 106 Km2). Despite the previous overestimation of the Amazon plume area due to the influence of rainfall (>16%), our calculated annual CO2 flux based on rainfall-corrected sea surface CO2 fugacity confirms that the Amazon River plume is an atmospheric CO2 sink of global importance (-7.61 ± 1.01 to -7.85 ± 1.02 Tg C year-1). Yet, we show that current sea-air CO2 flux assessments for the tropical Atlantic could be overestimated in about 10% by neglecting the CO2 sink associated to the Amazon plume. Thus, including the Amazon plume, the sea-air CO2 exchange for the tropical Atlantic is estimated to be 81.1 ± 1.1 to 81.5 ± 1.1 Tg C year-1"
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Re: Carbon Cycle
« Reply #288 on: April 21, 2016, 06:48:59 PM »
Eight years ago a group of industry representatives and scientists had a series of meetings to design a path forward for how the states , Calif. Oregon and Washington could address their shared needs for a California current acidification plan.
 Because of the problems with hatchery raised oysters the number one priority was to design a way to monitor the seawater intakes for a real time measure of the saturation state of aragonite. The technology wasn't available at the time but it has since been developed and put into use. One of the hatchery owners has described it as putting headlights on your car. Hatcheries have been able to monitor and modify seawater saturation and most of the hatchery crashes of oysters have been eliminated. Many of those instruments and methodologies are now being applied to other hatcheries on the U.S. east coast as well as in the Gulf states.
 Another major goal was setting up a monitoring network and although this is a goal that is never going to be as complete as the spacial variability of the problem demands there has been great headway made. The monitoring equipment at the hatcheries along the coast is an import advancement to the already existing offshore component of monitoring.
 A third goal we talked about was some sort of biological proxy for the effects of acidification on calcifying organisms in the wild. Bednarsek et al 2016 have published a paper utilizing
Pteropods as proxy for the biological effects of acidification in Eastern boundary currents around the world.
  http://www.imber.info/Products/Newsletters/Issue-n-30-April-2016#toc_3_6


 

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Re: Carbon Cycle
« Reply #289 on: April 22, 2016, 04:50:50 PM »
The negative effects of O/A on Pteropods has been the subject of several posts above. Here is one showing a large negative impact on a temperate Copepod species. Pteropods and copepods are important prey species for fish and animals further up the food chain. Negative effects on these two species will likely affect higher trophic levels and as a result fisheries.

 "The critical role played by copepods in ocean ecology and biogeochemistry warrants an understanding of how these animals may respond to ocean acidification (OA). Whilst an appreciation of the potential direct effects of OA, due to elevated pCO2, on copepods is improving, little is known about the indirect impacts acting via bottom-up (food quality) effects. We assessed, for the first time, the chronic effects of direct and/or indirect exposures to elevated pCO2 on the behaviour, vital rates, chemical and biochemical stoichiometry of the calanoid copepod Acartia tonsa. Bottom-up effects of elevated pCO2 caused species-specific biochemical changes to the phytoplanktonic feed, which adversely affected copepod population structure and decreased recruitment by 30%. The direct impact of elevated pCO2 caused gender-specific respiratory responses in A.tonsa adults, stimulating an enhanced respiration rate in males (> 2-fold), and a suppressed respiratory response in females when coupled with indirect elevated pCO2 exposures. Under the combined indirect+direct exposure, carbon trophic transfer efficiency from phytoplankton-to-zooplankton declined to < 50% of control populations, with a commensurate decrease in recruitment. For the first time an explicit role was demonstrated for biochemical stoichiometry in shaping copepod trophic dynamics. The altered biochemical composition of the CO2-exposed prey affected the biochemical stoichiometry of the copepods, which could have ramifications for production of higher tropic levels, notably fisheries. Our work indicates that the control of phytoplankton and the support of higher trophic levels involving copepods have clear potential to be adversely affected under future OA scenarios."


Cripps G., Flynn K. J. & Lindeque P. K., 2016. Ocean acidification affects the phyto-zoo plankton trophic transfer efficiency. PLoS ONE 11(4):e0151739. Article.

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Re: Carbon Cycle
« Reply #290 on: April 27, 2016, 11:14:11 PM »
The linked research indicates that evidence of anthropogenically-driven reductions on oceanic oxygen can currently be observed in limited parts of the ocean and will become widespread by 2030-2040 (see image):

Matthew C. Long, Curtis Deutsch & Taka Ito (29 February 2016), "Finding forced trends in oceanic oxygen", Global Biogeochemical Cycles, DOI: 10.1002/2015GB005310


http://onlinelibrary.wiley.com/doi/10.1002/2015GB005310/abstract

Abstract: "Anthropogenically forced trends in oceanic dissolved oxygen are evaluated in Earth system models in the context of natural variability. A large ensemble of a single Earth system model is used to clearly identify the forced component of change in interior oxygen distributions and to evaluate the magnitude of this signal relative to noise generated by internal climate variability. The time of emergence of forced trends is quantified on the basis of anomalies in oxygen concentrations and trends. We find that the forced signal should already be evident in the southern Indian Ocean and parts of the eastern tropical Pacific and Atlantic basins; widespread detection of forced deoxygenation is possible by 2030–2040. In addition to considering spatially discrete metrics of detection, we evaluate the similarity of the spatial structures associated with natural variability and the forced trend. Outside of the subtropics, these patterns are not wholly distinct on the isopycnal surfaces considered, and therefore, this approach does not provide significantly advanced detection. Our results clearly demonstrate the strong impact of natural climate variability on interior oxygen distributions, providing an important context for interpreting observations."

See also:
http://phys.org/news/2016-04-widespread-loss-ocean-oxygen-2030s.html

Extract: "A reduction in the amount of oxygen dissolved in the oceans due to climate change is already discernible in some parts of the world and should be evident across large regions of the oceans between 2030 and 2040, according to a new study led by the National Center for Atmospheric Research (NCAR)."

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Re: Carbon Cycle
« Reply #291 on: April 29, 2016, 07:40:11 PM »
As a follow-on by my Reply #290, Robert Scribbler has a nice article about the NCAR study on the climate change induced depletion of oxygen in most of the oceans by 2030:

https://robertscribbler.com/2016/04/28/ncar-global-temperature-increase-depletes-oxygen-in-most-ocean-zones-by-the-2030s/

Extract: "NCAR: Global Temperature Increase To Lower Oxygen Content of Most Ocean Zones by the 2030s
A reduction in the amount of oxygen dissolved in the oceans due to climate change is already discernible in some parts of the world and should be evident across large regions of the oceans between 2030 and 2040. — The National Center for Atmospheric Research in a press release on April 27th.
Loss of oxygen in the world’s oceans. It’s one of those really, really bad effects of a human-forced warming of our Earth. One of the those climate monsters in the closet that Steve Pacala talks about. The kind of thing we really don’t want to set loose.



The new NCAR study provides an excellent description of how warming the world’s surface waters can reduce ocean oxygen levels:
The entire ocean—from the depths to the shallows—gets its oxygen supply from the surface, either directly from the atmosphere or from phytoplankton, which release oxygen into the water through photosynthesis. Warming surface waters, however, absorb less oxygen. And in a double whammy, the oxygen that is absorbed has a more difficult time traveling deeper into the ocean. That’s because as water heats up, it expands, becoming lighter than the water below it and less likely to sink.



The fact that the NCAR study indicates that global warming has already reduced ocean oxygen levels in a region that is producing both dead zones and, in the case of Nambia, periods during which hydrogen sulfide producing bacteria appear at the surface, is cause for some concern. For by the 2030s, the NCAR model study indicates that global warming will be actively reducing ocean oxygen levels across the vast majority of the North Pacific, a majority of the South Pacific, most of the South Atlantic, and pretty much all of the Indian Ocean region covered in the new research. This raises the risk that open water dead zones like the ones seen off Africa and even hydrogen sulfide producing hot spots like Nambia may begin to creep into other regions of the world ocean — generating further threats to sea life, to fishing industry, and to human beings who depend on healthy oceans for livelihood and for life."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Carbon Cycle
« Reply #292 on: May 02, 2016, 07:54:36 PM »
The linked reference indicates that when the Amazon forest is subjected to repeated droughts that it sequesters progressive less carbon with each new drought.  Thus as we are now in a positive PDO phase we can expect that the Amazon (and other rainforests) will progressive absorb less carbon, for at least the next 20 to 30 years):

T.R. Feldpausch e.at. (30 April 2016), "Amazon forest response to repeated droughts", Global Biogeochemical Cycles", DOI: 10.1002/2015GB005133

http://onlinelibrary.wiley.com/doi/10.1002/2015GB005133/abstract

Abstract: "The Amazon Basin has experienced more variable climate over the last decade, with a severe and widespread drought in 2005 causing large basin-wide losses of biomass. A drought of similar climatological magnitude occurred again in 2010; however, there has been no basin-wide ground-based evaluation of effects on vegetation. We examine to what extent the 2010 drought affected forest dynamics using ground-based observations of mortality and growth utilizing data from an extensive forest plot network. We find that during the 2010 drought interval, forests did not gain biomass (net change: −0.43 Mg ha-1, CI: −1.11, 0.19, n = 97), regardless of whether forests experienced precipitation deficit anomalies. This loss contrasted with a long-term biomass sink during the baseline pre-2010 drought period (1998 − pre-2010) of 1.33 Mg ha-1 yr-1 (CI: 0.90, 1.74, p < 0.01). The resulting net impact of the 2010 drought (i.e., reversal of the baseline net sink) was −1.95 Mg ha-1 yr-1 (CI:−2.77, −1.18; p < 0.001). This net biomass impact was driven by an increase in biomass mortality (1.45 Mg ha-1 yr-1 CI: 0.66, 2.25, p < 0.001), and a decline in biomass productivity (−0.50 Mg ha-1 yr-1, CI:−0.78, −0.31; p < 0.001). Surprisingly, the magnitude of the losses through tree mortality was unrelated to estimated local precipitation anomalies, and was independent of estimated local pre-2010 drought history. Thus, there was no evidence that pre-2010 droughts compounded the effects of the 2010 drought. We detected a systematic basin-wide impact of drought on tree growth rates across Amazonia, with this suppression of productivity driven by moisture deficits in 2010, an impact which was not apparent during the 2005 event [Phillips et al., 2009]. Based on these ground data, both live biomass in trees and corresponding estimates of live biomass in roots, we estimate that intact forests in Amazonia were carbon neutral in 2010 (−0.07 PgC yr-1 CI:−0.42, 0.23), consistent with results from an independent analysis of airborne estimates of land-atmospheric fluxes during 2010 [Gatti et al., 2014]. Relative to the long-term mean, the 2010 drought resulted in a reduction in biomass carbon uptake of 1.1 PgC, compared to 1.6 PgC for the 2005 event [Phillips et al. 2009]."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Carbon Cycle
« Reply #293 on: May 03, 2016, 09:08:20 PM »
The linked reference indicates there are well over 1 trillion species of microbes in the oceans and earth (mostly in the soil as indicated in the attached image).  As the Earth warms-up a fraction of these microbes will likely contribute to the acceleration of carbon emissions from microbes:

Kenneth J. Locey and Jay T. Lennon (2016), "Scaling laws predict global microbial diversity", PNAS, doi: 10.1073/pnas.1521291113

http://www.pnas.org/content/early/2016/04/26/1521291113.full

Abstract: "Scaling laws underpin unifying theories of biodiversity and are among the most predictively powerful relationships in biology. However, scaling laws developed for plants and animals often go untested or fail to hold for microorganisms. As a result, it is unclear whether scaling laws of biodiversity will span evolutionarily distant domains of life that encompass all modes of metabolism and scales of abundance. Using a global-scale compilation of ∼35,000 sites and ∼5.6⋅106 species, including the largest ever inventory of high-throughput molecular data and one of the largest compilations of plant and animal community data, we show similar rates of scaling in commonness and rarity across microorganisms and macroscopic plants and animals. We document a universal dominance scaling law that holds across 30 orders of magnitude, an unprecedented expanse that predicts the abundance of dominant ocean bacteria. In combining this scaling law with the lognormal model of biodiversity, we predict that Earth is home to upward of 1 trillion (1012) microbial species. Microbial biodiversity seems greater than ever anticipated yet predictable from the smallest to the largest microbiome."

Conclusion: "We estimate that Earth is inhabited by 1011–1012 microbial species. This prediction is based on ecological theory reformulated for large-scale predictions, an expansive dominance scaling law, a richness scaling relationship with empirical and theoretical support, and the largest molecular surveys compiled to date. The profound magnitude of our prediction for Earth’s microbial diversity stresses the need for continued investigation. We expect the dominance scaling law that we uncovered to be valuable in predicting richness, commonness, and rarity across all scales of abundance. To move forward, biologists will need to push beyond current computational limits and increase their investment in collaborative sampling efforts to catalog Earth’s microbial diversity. For context, ∼104 species have been cultured, less than 105 species are represented by classified sequences, and the entirety of the EMP has cataloged less than 107 species, 29% of which were only detected twice. Powerful relationships like those documented here and a greater unified study of commonness and rarity will greatly contribute to finding the potentially 99.999% of microbial taxa that remain undiscovered."

Caption: "Fig. 2. The dominance-abundance scaling law (dashed red line) predicts the abundance of the most abundant microbial taxa (Nmax) up to global scales. The pink hull is the 95% prediction interval for the regression based on 3,000 sites chosen by stratified random sampling (red heat map) from our microbial data compilation. Gray cross-hairs are ranges of published estimates of N and Nmax for large microbiomes, including Earth (Materials and Methods, Approximating Ranges of Nmax for Large Microbiomes). The light-gray dashed line is the 1:1 relationship. The scaling equation and r2 only pertain to the scatterplot data."


See also:
http://www.upi.com/Science_News/2016/05/03/Study-Earth-may-host-1-trillion-species/7691462279730/

Extract: "Using a series of large data sets, ecological models and global scaling laws, researchers estimated that Earth likely hosts upwards of 1 trillion species. Their models incorporated data sets on microbial, plant and animal communities compiled by governments, academic institutions and citizen scientists."
« Last Edit: May 03, 2016, 09:43:06 PM by AbruptSLR »
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AbruptSLR

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Re: Carbon Cycle
« Reply #294 on: May 06, 2016, 05:30:24 PM »
The linked reference finds that the archaea & bacteria on the deep seafloor are sensitive to climate change:

Roberto Danovaro, Massimiliano Molari, Cinzia Corinaldesi and Antonio Dell’Anno (29 Apr 2016), "Macroecological drivers of archaea and bacteria in benthic deep-sea ecosystems", Science Advances, Vol. 2, no. 4, e1500961, DOI: 10.1126/sciadv.1500961

http://advances.sciencemag.org/content/2/4/e1500961

Abstract: "Bacteria and archaea dominate the biomass of benthic deep-sea ecosystems at all latitudes, playing a crucial role in global biogeochemical cycles, but their macroscale patterns and macroecological drivers are still largely unknown. We show the results of the most extensive field study conducted so far to investigate patterns and drivers of the distribution and structure of benthic prokaryote assemblages from 228 samples collected at latitudes comprising 34°N to 79°N, and from ca. 400- to 5570-m depth. We provide evidence that, in deep-sea ecosystems, benthic bacterial and archaeal abundances significantly increase from middle to high latitudes, with patterns more pronounced for archaea, and particularly for Marine Group I Thaumarchaeota. Our results also reveal that different microbial components show varying sensitivities to changes in temperature conditions and food supply. We conclude that climate change will primarily affect deep-sea benthic archaea, with important consequences on global biogeochemical cycles, particularly at high latitudes."

See also:
https://www.skepticalscience.com/deep-sea-microbes-key-ocean-climate-feedback.html

Extract: "A new study published Friday in Science Advances finds that seabed bacteria and archaea (which look like bacteria but have very different genetics and biochemistry) are sensitive to climate. Because their habitat covers 65% of the entire globe, they form a huge part of the biosphere and are important in the regulation of carbon in the deep ocean, which affects long-term climate change."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

werther

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Re: Carbon Cycle
« Reply #295 on: May 07, 2016, 09:29:06 AM »
Usually, I only look at the Methane numbers for Barrow every once a while. Today, I visited some other places and took the period 1995-2016 to capture both super-El Nino’s.
This is an overview of Northern Hemisphere graphs:



And this for the SH:



On first sight, all show a steepening of the graph since ’06. Most even steeper since ’14. Most show a bump for 1998-2000 too. But the uphill drive since ’14 is worse.

The effect is biggest in the Polar regions. Even at the South Pole. Mind, South Pole, Mauna Loa, Summit; they’re all stations at app. 3000 m ASL.  At SL, look at Ny Alesund (Svalbard) or Crozet Island (Roaring Forties), Palmer Station (Antarctic Peninsula).

Especially those graphs around the West Wind Drift circling Antarctica make me nervous… Have to have a better look there.


Bruce Steele

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Re: Carbon Cycle
« Reply #296 on: May 13, 2016, 05:03:48 PM »
Abstract
We assess the potential magnitude of the economic effects of an ocean acidification (OA) catastrophe by focusing on marine ecosystem services most likely to be affected. It is scientifically plausible that by 2200 OA could cause a complete collapse of marine capture fisheries, complete destruction of coral reefs, and significant rearrangement of marine ecosystems. Upper-bound values for losses from the first two effects range from 97 to 301 billion 2014 dollars per year (0.09 - 0.28% of current world GDP). We argue that aquaculture output would not be reduced, due to the high potential for adaptation by this young industry.

https://www.aeaweb.org/articles?id=10.1257/aer.p20161105

"an ocean acidification ( OA ) catastrophe"  is a quote that pikes my interest. So for $9.50 I will get the full article. I somehow doubt an economist could put a value on the collapse  or partial collapse of the carbon pump.

AbruptSLR

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Re: Carbon Cycle
« Reply #297 on: May 18, 2016, 05:13:49 PM »
The linked SkS article describes the particulars of ocean deoxygenation, and indicates that it "… is the 3rd but less-reported member of an evil climate change trinity, along with global warming and ocean acidification."

https://www.skepticalscience.com/Ocean_Oxygen_another_climate_shoe_dropping.html

Extract: "Ocean deoxygenation is the 3rd but less-reported member of an evil climate change trinity, along with global warming and ocean acidification. It is not so much another shoe dropping out of our CO2 emissions as it is a large boot kicking ocean ecosystems, with significant knock-on impacts for hundreds of millions of people who depend on the oceans for a living, and with feedbacks on climate."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

TerryM

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Re: Carbon Cycle
« Reply #298 on: May 18, 2016, 08:07:05 PM »
Wonder if Bruce Steel could comment on oceanic oxygen loss. Is this something else we should fear in the days ahead?
Terry

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Re: Carbon Cycle
« Reply #299 on: May 19, 2016, 07:20:23 AM »
Terry, I am sure I couldn't do a better job describing the links between decreasing oxygen, increasing acidity and ocean warming than the skeptical science piece describes. I can link some added insights perhaps but in the head spinning run up in papers and research perhaps even a day or two adds to the information matrix we are able to pull information from. My head spins.
 I have been posting information about the precarious position Pteropods are in. Most of the studies have been done on the shell dissolution of adult animals. 
Today I read an article that finds Pteropod eggs are even more at threat than the adults. Pinning down a date for when dissolved CO2 ( pCO2 ) reaches 1200 at 600 meters in the Antarctic may be open for debate but an 80% reduction in pteropod egg survival is decades and not centuries away.
 Living animals that can make a diel migration from the surface to 600 meters carry surface production to depth , part of that is in fecal transport and part in animals that die at depth. Going deeper isn't an option when the shell material is dissolved at greater depths and lower pH. As pteropods are diminished smaller phytoplankton will thrive in surface waters as one of their main predators decrease. The strength of the carbon pump will diminish  however as the smaller organisms will not ballast surface production to depth as efficiently as heavier shelled pteropods . They won't make a diel migration and they won't produce carbonate shells . They will stay closer to the surface where bacterial remineralization will result in CO2 and nutrients being released closer to the surface where CO2 and nitrogen can re-enter the atmosphere.

   https://news-oceanacidification-icc.org/2016/05/18/pteropod-eggs-released-at-high-pco2-lack-resilience-to-ocean-acidification/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+wordpress%2FlRgb+%28Ocean+acidification%29

The switch from larger to smaller phytoplankton has been modeled with an eye to the efficacy of the carbon pump. A 30 % reduction by ~ 2030 is at best a ballpark number considering the potential Pteropod crash hadn't been well described. Maybe the Pteropods can somehow adjust their preferred depth habitats and hang in there a couple decades extra but I think they are as threatened as the coral reef systems . 

  http://marine.unc.edu/event/seminar-dr-curtis-deutsch-uwash/

Where surface productivity releases it's CO2 via bacterial remineralization is a big deal. The depth that the ballasting of that productivity reaches before acidification eats away the carbonate shell that drives much of the ballast weight and stops it's descent is also important. Low oxygen levels are  at mid depth as the bacterial remineralization consumes oxygen where organic matter is released from it's descent. As acidification builds the depth that calcium dissolves gets closer to the surface. Much of the West Coast of North America will be bathed in undersaturated waters from surface to depth by 2040-2050 for several months each year. The largest problems in low oxygen will be expansions of already existing oxygen minima areas largely associated with eastern boundary currents, the Canary current, the Humboldt current, the California current and the Benguela current. There has also been very low pH levels measured in upwelling areas of southern Oman.
 It is difficult to look past the next eighty years. Carbon released by permafrost melt, boreal and tropical fires and potential shallow water hydrate releases will add to atmospheric CO2 levels long after athropogenic fossil fuel contributions begin to wane. The amount of carbon released in those feedbacks will likely be met with a compromised carbon pump. The CO2 therefore will stay in the atmosphere longer and cause extra heating.