How much can El Niño be blamed for the jump in CO2?

Something unusual happened in April this year. Between March and April there was a record month to month jump in atmospheric CO2 recorded at Mauna Loa. It went up by 2.71 ppmv. That's 0.6 ppmv higher than the previous highest month to month jump (2.11 ppmv) back in April 2004. However it's not wise to focus on month to month variations. For example, March could have been lower than expected, which would make the jump seem larger than it should be. (It wasn't.) This article explores some of what causes atmospheric CO2 to go up and down. It's not the answer to everything, however I learnt a lot doing the research and I have some unanswered questions too (like a quantitative answer to the title of this article). (Let me know if you see any mistakes I may have made.)

The chart below shows the month by month increase in atmospheric CO2 since the late 1950s. Hover over the chart for the values. The most recent is April at 407.57 ppmv.

Figure 1 | Monthly CO2 at Mauna Loa. Data source: SCRIPPS CO2 Program

Is CO2 sentient? Ari Halperin and Anthony Watts claim the carbon cycle is "fraud"

After a rattled Anthony Watts spat out dummies yesterday, today he's going for broke and has posted an article denying the carbon cycle (archived here). You may recall how, earlier this week Anthony fibbed to his readers, claiming "I don’t like to use the word “fraud”"? Well, here he is not five days later with a blog article alleging IPCC fraud. The supposed fraud? Well, it turns out that Anthony's guest blogger doesn't believe in the carbon cycle. You could say he's a carbon cycle denier.

Excuse the lengthy article. It's not exactly a primer, but there's some detail. I figured people who've never heard of the carbon cycle might find it useful. (The image is because at one point, Ari seems to be suggesting that CO₂ is sentient.)

The carbon cycle

The carbon cycle has been described as a fast cycle plus a slow cycle. The fast cycle involves short term fluxes as happens with photosynthesis (an annual cycle) and other short term processes of the order of decades (vegetative growth and decay etc). The slow cycle involves medium term fluxes on a timescale of centuries, particularly the exchange between the ocean and atmosphere, as well as very slow chemical and geological processes (thousands to millions of years), such as weathering of rocks.

No, water vapour is not what's *causing* global warming

Tim Ball wrote at WUWT an article with a misleading headline (as is usual at WUWT)):

Thanks To The IPCC, the Public Doesn’t Know Water Vapor Is Most Important Greenhouse Gas

This is a "back to basics" article. The basics being: CO2 is a greenhouse gas. As atmospheric CO2 increases, the earth gets hotter. As temperatures rise, more water evaporates.  Water is also a greenhouse gas. More atmospheric water vapour means the world gets hotter still.

The lack of basic scientific knowledge displayed at WUWT sometimes surprises even me.

Tim Ball FAILS Carbon Cycle 101 at WUWT

I'm flat out getting a few things done before the Christmas break, so this is just a short article. It's necessary because if you read WUWT, you'll leave it scratching your head wondering how it could claim to be a climate site.

Before I begin, if anyone wants to read up on the carbon cycle, one of the best sites that describes it for the non-scientists out there, is NASA's Earth Observatory website.

NASA's OCO-2 Satellite

The topic is NASA's OCO-2 project, which was launched earlier this year. NASA gave a report at AGU. They've been collecting data since early September. I'll let the scientists tell it, if you have the time:

It takes 16 days to get a full set of global data, with a million readings a reading a day which yields tens of thousands of data points. What they have to do is determine differences of maybe only one or two parts per million (there are around 400 ppm of CO2 in the air today).

I've been wanting to write this for a few days now, and have been prompted to get a move on by one of the sillier articles from conspiracy theorising Tim Ball (archived here).

Irons in the fire at WUWT...well there might not be so much in the oceans these days

Frequently Anthony Watts (owner of the blog WUWT) copies and pastes a press release about a new scientific paper so his readers can have something new to mock. He usually starts his headline with the word "Claim", just so his followers know they aren't supposed to "believe" science.  Many of his followers aren't too bright and they need these clues so they can tell how to respond.

Today Anthony puts aside his "claim" headline in favour of this (archived here):

Warming climates intensify greenhouse gas given out by oceans

From the University of Edinburgh and the department of soda pop science, comes something we already knew. I wonder who approved the grant for this one?

Anthony reckons this is something "we already knew". He doesn't spell out what he "already knew" but going by his "soda pop" reference, it's fairly clear that the paper discusses something that he didn't know already and he doesn't know now. He's confusing the findings of this study with the fact that CO2 dissolved in water will be released as the water warms. But that's not at all what this study was about. The study is about diatoms, silica, iron and carbon. (Click here to read more if you're on the home page.)

Dunning and Kruger in the Cenozoic Era at WUWT - very uplifting :)

Anthony Watts has a new article on his blog today (archived here).  It's about a paper in Nature about some research estimating the amount of CO2 released by tectonic activity, I suppose you'd call it.  When mountains are formed and fresh rock is exposed the scientists postulated that there was more chemical reactions going on than previously thought, releasing CO2.  The work was done by Mark A. Torres, A. Joshua West & Gaojun Li.

As usual, Anthony didn't link to the paper or press release itself but it wasn't hard to find either.  The paper has a dry title: Sulphide oxidation and carbonate dissolution as a source of CO2 over geological timescales.

Some science media outlets jazzed up the research up with a catchy headline, which Anthony borrowed (and no sign of a "claim"):

The Goldilocks principle: New hypothesis explains earth's continued habitability

Goldilocks & the 3 bears minus Goldilocks.
Robert Southey 1837

The Goldilocks principle was invoked because the paper was about how CO2 keeps the earth "not too hot and not too cold" - though it isn't always "just right" for everyone and everything, is it.


Anyway, the scientists worked out that over the Cenozoic era, marine analysis suggests there was extensive weathering of silicates when mountains were popping up all over the world, but there wasn't enough CO2 released from volcanic eruptions to balance the books.  They reckoned that "The resulting imbalance would have depleted the atmosphere of all CO2 within a few million years7."

So they put on their thinking caps and had a close look at some mountains in Peru.  They figured that there was CO2 being released from fresh rock exposed during tectonic activity.  The way I read their research, what they are saying is that when there's a lot of tectonic activity there was both more CO2 absorbed by weathering as well as more CO2 released by chemical reactions.

This is all on geological time scales, needless to say.  We're not talking in time frames of decades - this is the slow carbon cycle over thousands to millions of years.  That's for the CO2 absorption by silicate weathering and the release by chemical activity.  If volcanoes are big enough they can affect CO2 on much shorter time frames.

From the University of Southern California:

Torres and West studied rocks taken from the Andes mountain range in Peru and found that weathering processes affecting rocks released far more carbon than previously estimated, which motivated them to consider the global implications of CO2 release during mountain formation. ...

...Like many other large mountain ranges, such as the great Himalayas, the Andes began to form during the Cenozoic period, which began about 60 million years ago and happened to coincide with a major perturbation in the cycling of atmospheric carbon dioxide.

Using marine records of the long-term carbon cycle, Torres, West and Li reconstructed the balance between CO2 release and uptake caused by the uplift of large mountain ranges and found that the release of CO2 release by rock weathering may have played a large, but thus far unrecognized, role in regulating the concentration of atmospheric carbon dioxide over the last roughly 60 million years.

(If you go to the USC website, I suggest use Firefox or IE, not Chrome. It's not Chrome-friendly.  But the USC has the full press release.  Other sites have only got a short version.)

Here's a link to one of NASA's Earth Observatory articles - on the slow carbon cycle and more.

From the WUWT comments

Anthony didn't have anything to add to his copied press release.  The rabble, they are another story. Get a load of this comment from devijvers, who is crying out for someone to call Poe when s/he strums a variation on the "scientists don't know nuffin'" theme:

March 20, 2014 at 1:10 am
The CO2 cycle:
Ocean plant life syncs to the bottom, becomes part of the sediment and eventually becomes rock. This is how CO2 is sequestered in rock.The tectonic conveyor belt slowly takes the ocean floor to the subduction zones, melting the rock by means of magma.The CO2 now mixed in magma is ejected by volcanoes. Wheatering of the newly formed rocks releases CO2.
This article is pure nonsense. More CO2 needs to be released by the wheatering than is used for the wheatering, otherwise we would have ran out long time ago. Where did these people get their degrees?

Matthijs seems to think we could end up like Venus in the blink of an eye - or maybe like Mars and says:

March 20, 2014 at 1:16 am
Another one that claims nature is in balance.
It is not.
It is a chaotic system that will flow from state to state depending on events that occur.
No way of telling what the next state is.

AleaJactaEst has it all figured out.  Scientists can pack up and go home:

March 20, 2014 at 1:17 am
…”While human-made atmospheric carbon dioxide increases are currently driving significant changes in the Earth’s climate….” and what would those be then?
The Earth has and will continue to go through several oxidising and reducing cycles (Devonian Permian e.g.) base solely on land mass accretion and subduction whose engine is the deep mantle plumes, the heat of which is derived from radioactive decay. The rest of our surface cycles are simply reactions, not balances, to the aforementioned cycles.

Paul Pierett calls on scientists to lend authority to his argument that scientists don't know nuffin' - (yeah, he's a bit mixed up) - but he's yours, most sincerely, if you'll take him:

March 20, 2014 at 1:29 am
I think they are close but have the cart before the horse. They still blame man. Too, not too many look beyond man for command and control of CO2 levels and there is the fail point.
Let’s begin with Milankovitch Cycles and Sunspot Cycles for the cause in geological cycles. From there gain and understanding of Topography shifts North and South of the Equator As the Earth emerges from and Ice Age and Returns again with mini-ice ages in the middle.
The Glaciers, Polar Ice Caps store the excess CO2 and releases them in the Ocean exchange as the Earth warms up and Topography expands and is allowed to expand. For example, when Lord Monckton testified before Congress a couple of years ago, the woman tree ring scientist testified that the tree line in the Sierra was higher for tree stumps were at a much higher elevation than at the present tree line. Thus, less Glaciers and Polar Ice mass released more CO2 to the Oceans and more provided for Topography at higher elevations and Latitudes.
As for the Pyrite, adjustments were made as much for the Volcanoes over time which we saw with Mt. Pinatubo.
Most Sincerely
Paul Pierett 

Talking of being mixed up.  A prize for anyone who can figure out what is going on in Mike Alger's little brain when he says:

March 20, 2014 at 1:39 am
Once again there is an overriding paradigm assumption that it is CO2 that is the main driver of the climatic system throughout geologic history…an assumption that I think is flawed in its very core. Even the warmists admit that the direct contribution of another doubling of CO2 is probably at most 1degree C…it’s the feedbacks that cause the catastrophic warming they are so worried about. But the feedbacks aren’t caused directly by CO2, they are caused by the slight warming the CO2 allegedly causes. So why focus on what controls the CO2 throughout geologic history? Instead focus on what causes the warming and cooling, which probably has much more to do with CO2 concentrations than the other way around.

My oh my, and I've hardly skipped over any comments.  Dunning and Kruger would have a field day at WUWT today.  Okay, just one more.  This time from our good friend, Leo Geiger, who is no doubt destined for the WUWT bin sooner rather than later:

Leo Geiger says:

March 20, 2014 at 3:36 am
I wonder what the criteria is for deciding whether or not published research needs to be introduced here with the word “Claim:” added as a prefix in the title? This one avoids that particular characterization.

---

Mark A. Torres, A. Joshua West & Gaojun Li. "Sulphide oxidation and carbonate dissolution as a source of CO2 over geological timescales." Nature 507, 346–349 (20 March 2014) doi:10.1038/nature13030

CO2 is plant food? Not on your nellie, sez Anthony (Pavlov) Watts and his dogs!

Did anyone say deniers are nuts?  Here is a paper not just telling everyone that plants are using a heap more CO2, but quantifying just how much more CO2 has been absorbed.

How does Anthony Watts react?  After all his articles about how "CO2 is plant food", you'd think he'd be shouting from the rooftops that at last those wretched scientists started listening to science deniers, wouldn't you.

But no! He's posted the press release under the headline:

Climate Craziness of the Week: Plants blamed for us not roasting since 1950

Perhaps Anthony didn't like the way the conclusion was worded, although it's on the cards that he hasn't read the paper itself.  He probably just skimmed the press release he copied and pasted.  This call to arms from Anthony Watts is archived here.


Anyway, this is what Elena Shevliakova and her team found:

The results of our study indicate that historical enhanced vegetation growth has avoided release of 251–274 GtC, about an additional 85 ppm of atmospheric CO2 concentration, and a warming of 0.31 ± 0.06 °C. To accurately predict observed trends in both temperature and the atmospheric CO2 concentration over the 20th century, ESMs need to account for the interaction of LUC and enhanced vegetation growth, including vegetation regrowth on the secondary lands. CO2 fertilization is a plausible but debated mechanism for the ongoing land carbon sink. The empirical evidence for enhanced vegetation growth under elevated CO2 remains equivocal (29–32). The model used here does not include nitrogen or phosphorus limitations on carbon uptake. Some modeling (33) and observational (34–36) studies have found that nitrogen availability has not significantly affected global carbon uptake over the 20th century, whereas others have reached the opposite conclusion (37). The magnitude and the sign of the future net land carbon flux will impact the atmospheric CO2 growth rate, climate change, and any efforts to mitigate it. Because of the importance of the land sink in reconciling atmospheric CO2 and climate records, this study adds urgency to independently test and isolate the mechanisms responsible for the growing terrestrial C sink.

So the world would most probably have been quite a bit hotter already if not for the enhanced vegetation growth. You'll notice their caution though.  "The empirical evidence for enhanced vegetation growth remains equivocal." and "The model used here does not include nitrogen or phosphorus limitations on carbon uptake."

The researchers used a coupled climate–carbon cycle model (ESM2G) and gridded land use changes from 1700 to 2005. They "conducted three types of CO2 emissions-driven experiments from 1861 to 2005: historical (EH), historical without LUC (land use change)  (EHnoLU), and historical without the CO2 fertilization effect on vegetation (EHnoFR)".

The full paper is available at PNAS for those who are interested.  It reads well.

Shevliakova, Elena, et al. "Historical warming reduced due to enhanced land carbon uptake." Proceedings of the National Academy of Sciences (2013): 201314047. doi: 10.1073/pnas.1314047110

From the WUWT comments

Because Anthony led the way deriding the research, almost all of his fans followed suit.  They are well-trained pups. Here's a selection (archived here):

JohnWho says:

October 16, 2013 at 1:23 pm
“Without plants, Earth would cook under billions of tons of additional carbon”
And who would care?
Without plants, all creatures that rely on the plants would die.
So, even if they “cooked”, who would be around to eat them?
We would not have a runaway carbon cycle without plants – the carbon cycle would quickly cease to revolve, would it not?

MattN says:

October 16, 2013 at 1:24 pm
Dumbest “what if” ever. Complete waste of money.

Bob Tisdale says who needs real science when you've got blog pseudo-science at WUWT?

October 16, 2013 at 1:26 pm
Someone wasted taxpayer dollars for this? Ridiculous!!!

JohnWho has another crack and says:

October 16, 2013 at 1:29 pm
Please, Lord, stop me from reading the above:
“The planet’s land-based carbon “sink” — or carbon-storage capacity — has kept 186 billion to 192 billion tons of carbon out of the atmosphere since the mid-20th century,…”
Uh, sure is a good thing those plants did that. Wonder if they were removing carbon from the atmosphere before the mid-20th century, too?

Bob, Missoula agrees with Bob Tisdale that science is for the literate, not the scientific illiterati at WUWT:

October 16, 2013 at 1:30 pm
Bob you said what I wanted to but without cussing.

Sparks thinks all science is a big joke and says:

October 16, 2013 at 1:32 pm
I loved it, needed a good laugh!

Philip Lee is the first person to commend the researchers for (not really) saying that "CO2 is plant food".  But he gets climate models woefully wrong when he says:

October 16, 2013 at 1:34 pm
A useful admission that CO2 is plant food that promotes plant growth (that will provide food for humans) and will limit temperature in ways not modeled by climate models.

richardscourtney isn't shy about displaying his ignorance of climate models either (he seems to think, wrongly, they are "made to fit" the past), and says:

October 16, 2013 at 1:40 pm
Friends:
The report says
“A unique value of this study is that it simulates the past, for which, unlike the future, we have observations,” Saleska said. “Past observations about climate and carbon dioxide provide a test about how good the model simulation was. If it’s right about the past, we should have more confidence in its ability to predict the future.

No competent scientist would utter such nonsensical drivel.

If a model cannot emulate the past there is reason to suppose it cannot predict the future.
But an ability of a model to emulate the past does NOT of itself provide any “confidence in its ability to predict the future”. This is because there are an infinite number of ways to make a model fit the past but there is only one way the future will occur.
Richard

Bennett In Vermont shows off the Dunning Kruger Effect and says:

October 16, 2013 at 1:46 pm
If they had asked an indoor gardener they could have learned that most plants don’t even hit their maximum growth potential until the level of CO2 is above 1200 ppm. That’s when they really start to take off.

Oh well, we can’t let simple facts get in the way of a Mad Magazine style scientific paper.

Tim Collins says:

October 16, 2013 at 1:56 pm
Wow what a lot of words, and I guess salary? In order to state the bleeding obvious except for the absurd postulation that plants will have so much to eat they will stop being carbon dioxide hungry – yeah right.

Stop paying these academidiots now and make them get proper jobs.

Chad Wozniak - does Chad ever think about what he writes?  He writes almost the same lot of words no matter what article he's commenting on:

October 16, 2013 at 2:15 pm
How desperate can these people get?
Will Happer at Princeton must be just shaking his head.

Okay, that's enough.  I'm sure you get the idea.  They'll never be happy these science deniers.  Scientists quantify an effect the deniers have been bleating about incessantly and the deniers still deny.  Like Pavlov's dog trained to growl whenever they come across some real science.  It doesn't matter if they agree with it or disagree.  As long as it's science they'll growl, mock, complain, tell the scientists how wrong they are and wail "if only they'd asked us deniers..."

Climate extremes, carbon cycle and more, while the illiterati at WUWT scream in protest at the onslaught of knowledge!

Climate extremes and the carbon cycle

Anthony Watts has copied and pasted a press release about a new paper in Nature, which discusses how extremes of weather can have an impact on the carbon cycle.  He called it "Vicious carbon cycles".  I saw this paper myself and thought it looked an interesting, if concerning, area of research.  It's by Reichstein et al and called: Climate extremes and the carbon cycle, Nature 500, 287–295 (15 August 2013) doi:10.1038/nature12350.

This diagram illustrates how extreme weather can affect the carbon cycle (from the Nature paper).  Click the image for a larger view:

Figure 2: Overview of how carbon flows may be triggered, or greatly altered, by extreme events.  Emphasis is on the potential contrast between the concurrent and delayed signal in the atmosphere. The arrows pointing upward represent additional carbon dioxide in the atmosphere. The arrows pointing downward indicate that carbon dioxide is removed more slowly from the atmosphere. Orange arrows stand for short-term and purple arrows for long-term effects. 

What the paper is suggesting  is that there is more evidence that indicates that climate extremes, like droughts and storms can cause terrestrial carbon to decline, which offsets to some extent the expected increase through plants' response to the higher atmospheric CO2. (C3 plants grow faster with higher CO2, all else being equal).  The paper sets out a way to help improve the understanding of these interactions.  There are a number of news articles about it if you want to read more.

The carbon cycle and the biosphere - up north in the boreal forests

I intended to keep this short, but the above paper reminded me of another recent paper, this time in Science.  It's by Graven et al and is called Enhanced Seasonal Exchange of CO2 by Northern Ecosystems Since 1960, Science DOI: 10.1126/science.1239207.  So far it's just in ScienceExpress, but should show up in the main journal soon-ish.

What this one is exploring is the reason for the extra bounce in the seasonal CO2 levels as time goes by, in some parts of the northern hemisphere.  In particular, they found that looking at CO2 levels at three to six kilometres up in the air in the region north of 45 degrees latitude, the seasonal amplitude of CO2 levels has shot up by 50% since the 1950s.  This contrasts with the seasonal amplitude of CO2 at 10° to 45°N, which has expanded by less than 25%.  They figure that it's got to do with changes in the boreal forests up north and signals a major shift in the carbon cycle.

They discount the effect of wildfire, oceans and fossil fuels.  After discussing their reasons, the authors state:

We are led to conclude that ecological changes in boreal and temperate forests are driving additional increases in the summertime uptake of carbon. This inference from atmospheric data is qualitatively consistent with expanding evidence for significant changes occurring in these ecosystems. Forest inventories show increased stand area and biomass (27, 29). Other ground-based studies show that evergreen shrubs and trees are migrating northward in response to warming (43–45), and fire, logging and other disturbances (46, 47) are shifting the age composition toward younger, early successional forests that experience shorter, more intense periods of seasonal carbon uptake (25, 48). Satellite observations generally show trends toward increased greenness in northern ecosystems (4), although many areas of the boreal forest show browning trends in recent decades (49, 50). The atmospheric evidence helps to quantify the aggregate effect of these, and other, types of ecological changes over the past 50 years. 

While the animation below is more about CO2 closer to the ground, you can see the difference between the northern and southern hemispheres in regard to seasonal fluctuations of CO2 (as featured on the NOAA website).  Use the bar at the bottom to skip through if you don't have the full three and a half minutes to be mesmerised by the whole video.

The carbon cycle and the biosphere

What interests me in these two papers is the fact that they are getting more into the detail of changes that are happening to the world.  Looking more specifically at changes in the biosphere and changes to the carbon cycle, not just the atmosphere and oceans, and considering how they affect the entire system.  I think in the next few years there will be a lot studies like these ones being published.

The WUWT Illiterati Society

Anyway, here are some comments from WUWT in response to the top paper.  The commenters have nothing but disdain for anyone who adds to the world's knowledge.  You think this is an enlightened era?  Well, it wouldn't be if the WUWT crowd had their way.  I'm amazed they made the effort to learn how to read and write given they have so much contempt for learning.

Here's a sample - two out of only six comments so far.  That's one in three commenters have declared their allegiance to the Illiterati Society:



FrankK says:
August 15, 2013 at 10:17 pm  A further example of the ever-increasing number of passengers on the global climate gravy train sucking the growing teat of “further research required” requests.

SMCG says:
August 15, 2013 at 9:45 pm  One day someone will write a paper that doesn’t say wtte “the demand for further research remains very high”


Now I've finished this there are more comments pouring in on WUWT.  I haven't done a count to see if the one in three illiterati still holds true.  However, I'll leave you with a comment without which no WUWT article would be complete - an ice age cometh!


Richard111 says:
August 15, 2013 at 11:26 pm  Whatever. None of this will stop the coming ice age.

CO2 is a resident of the atmosphere

Sometimes it's as if WUWT is going methodically through the list of SkepticalScience myths, trying valiantly to revive them.  This time someone called Gösta Pettersson is muddling the residence time of an individual CO2 molecule with the time taken for all the CO2 in the atmosphere to go through a complete carbon cycle or the time taken to get to a new equilibrium state in the earth system.

Edit: Lars Karlsson has made a couple of comments pointing out that the issues in Gösta Pettersson's article are not as simple as I made them out to be.  (See comments below).

Any individual molecule of CO2 will get used up in photosynthesis or absorbed by the ocean (at present the ocean is still a net absorber of CO2 rather than a net emitter, because of the partial pressure of atmospheric CO2). But no sooner does that happen than another molecule pops into the air to replace it - maybe in exchange with the ocean or via plant respiration.  And while all this is going on we keep adding more CO2 to the air and the oceans, by burning fossil fuels and other activities like land clearing.

That ongoing cycle between vegetation, oceans, soil and atmosphere determines the residence time of a single molecule.  The length of time taken before atmospheric CO2 reaches a new equilibrium is much longer - of the order of centuries to millenia.

I rather like this diagram from realclimate.org to get a sense of the time frames involved.  It's designed to illustrate climate sensitivity.  Click the diagram to see a larger version.

Source: RealClimate.Org

There are any number of diagrams of the carbon cycle. For example this one from the NASA/Globe program. (Click to enlarge):

Credit: NASA/Globe Program

In the comments a number of people point out the mistake Gösta Pettersson made. Some deniers refuse to accept it, but that's par for the course at WUWT.  The question remains - why does Anthony Watts promote these false myths on his blog?  It can't be for any good reason.