As readers of HotWhopper know by now, Anthony Watts peddles disinformation. He's scatty about it. He'll put up contradictory articles without batting an eyelid. There is no rhyme or reason to the various bits of pseudo-science he promotes. It ranges from "OMG it's insects" to "a massive ice age cometh" by 2020.
Up to 33% of the extra CO2 will stay in the air for a thousand years...
Today Anthony Watts claims (archived here):
One has to wonder though, since CO2 residence time has been said to be anywhere from five year to hundreds, or even thousands of years, with no solid agreement yet, how they can be so sure of themselves?He's wrong (again), of course. There is a reasonable understanding of how long CO2 stays in the air at least in human time frames. It might not be all that precise because it can't be all that easy to predict how the plants and oceans will respond, given the rapidity of the changes we're subjecting them to. There's no precedent.
Anthony is too lazy to read the science or else he's deliberately peddling lies. Or maybe it's just another example of how he doesn't have a clue. On par with his confusion over temperature anomalies and baselines.
He's wrong on his numbers, most definitely. There is no suggestion that CO2 only stays in the atmosphere for five years. And his "thousands of years" could be "hundreds of thousands of years". According to David Archer's 2005 research, a lot of CO2 would drop out in the first few decades if we stopped adding any at all. After 300 years it would have flattened out with somewhere between 17% and 33% of what we've added staying in the air for a thousand years. After 100,000 years there would still be about 7% of the added CO2 in the air.
Anthony Watts posts a ludicrous chart
Have a gander at this silly chart that Anthony put up. Click to enlarge it as always.
|Source: WUWT of course. Where else would you find such a dumb chart!|
Notice the age of the papers in the chart? The chart is all wrong even with the old papers. I checked out the Keeling and Bacestow paper (which, interestingly, says a lot about CFCs and the destruction of ozone). Needless to say, it doesn't say that CO2 can all drop out of the air in less than 10 years. In fact, here are some quotes (my bold italics):
As discussed below, the CO2 concentration of the atmosphere is likely to vary considerably over the next several hundred years. This time is too short for the atmosphere and ocean to attain equilibrium either with respect to climate or chemical processes....
... The present discussion principally emphasizes that the world’s oceans cannot be expected to remove a major fraction of the industrial CO2 from the air for a long time in comparison with the lifetime of human institutions. Although other mechanisms of CO2 withdrawal may exist, it is probably prudent to expect the concentration of atmospheric CO2 to persist above twice the preindustrial level for at least several centuries.
And I also checked his "100 years" from IPCC AR4. Anthony Watts is wrong again. Here is a quote:
While more than half of the CO2 emitted is currently removed from the atmosphere within a century, some fraction (about 20%) of emitted CO2 remains in the atmosphere for many millennia.
Do the sums
By my calculations by our actions we've added more than 900 billion tonnes of carbon dioxide to the air in only 150 years or so.
What Anthony Watts is claiming is that "someone said" that if we stopped adding CO2 to the air tomorrow, all that we've added could all be absorbed by the land and oceans in five years. All 900 billion tonnes of it. That represents about 255 billion tonnes of carbon. All being absorbed by plants and oceans in five years.
Think about that. The total mass of biomass, minus bacteria, is estimated at 560 billion tonnes. So far, plants have taken up about 25% of all the extra carbon we've dug up and thrown away. That's about 141 billion tonnes. Another 30% or around 170 billion tonnes has been absorbed by the oceans. It's unimaginable that plants could absorb, say, another 116 billion tonnes in only five years. Biology wouldn't allow it. Just as it's unimaginable that the waters of the world could absorb 140 billion tonnes of carbon in only five years. Physics wouldn't allow it.
The net flux into the ocean in 2000 was estimated at around 2 billion tonnes of carbon a year. For the oceans to absorb 140 billion tonnes in five years, that would be 28 billion tonnes a year or a fourteen fold increase. If we stopped adding CO2 to the air, each year the partial pressure of CO2 in the air would drop as CO2 was absorbed. So each year a bit less would be absorbed by the ocean. But even if the oceans could absorb at the same rate as in 2000, it would take 70 years to absorb 140 billion tonnes of carbon.
Leaving my basic calculations alone, scientists have done the sums and estimated how long it would take for carbon to be absorbed. As I said above, according to David Archer (2005), after about 300 years much of the added CO2 would have dropped out of the air but "17– 33% of the fossil fuel carbon will still reside in the atmosphere 1 kyr from now, decreasing to 10– 15% at 10 kyr, and 7% at 100 kyr".
Below is a graphic prepared by Robert Rohde of Global Warming Art.
|Image created by Robert A. Rohde / Global Warming Art|
There's fat chance of us stopping all CO2 emissions in the immediate future but a chance we can seriously cut them over the next two or three decades if we put our minds to it. The sooner we start in earnest the better.
Four degrees could be the limit for plant absorption of CO2
The article that Anthony Watts scoffed at when he wrote his "five year" residence time lines were as an introduction to a press release of a new paper. The paper by Friend et al in PNAS is about a study of plant uptake of CO2 (open access at the moment). The researchers found that at 4 degrees of warming, the biosphere will become saturated with carbon and will lose its capacity to absorb CO2 because of the heat and drought associated with global warming. Anthony as usual didn't provide a link to the paper or the press release, but the research is getting a bit of publicity. From the Cambridge press release:
As the world continues to warm, consequent events such as Boreal forest fires and mid-latitude droughts will release increasing amounts of carbon into the atmosphere - pushing temperatures ever higher.
Initially, higher atmospheric CO2 will encourage plant growth as more CO2 stimulates photosynthesis, say researchers. But the impact of a warmer world through drought will start to negate this natural balance until it reaches a saturation point.
The modelling shows that global warming of 4 degree will result in Earth’s vegetation becoming “dominated” by negative impacts - such as ‘moisture stress’, when plant cells have too little water - on a global scale.
Carbon-filled vegetation ‘sinks’ will likely become saturated at this point, they say, flat-lining further absorption of atmospheric CO2. Without such major natural CO2 drains, atmospheric carbon will start to increase more rapidly - driving further climate change.
From the paper itself:
Vegetation carbon residence time not only is important because of its contribution to GVM [global vegetation model] uncertainty, but also represents a key stage in the cascade of carbon from the atmosphere, through various organic and inorganic surface pools, and back to the atmosphere. Changes in vegetation carbon residence times can cause major shifts in the distribution of carbon between pools, overall fluxes, and the time constants of terrestrial carbon transitions, with consequences for the land carbon balance and the associated state of ecosystems.
From the WUWT comments
Anthony Watts has the audience he deserves. There are a few silly people who talk about how the temperature in their area can vary a lot in a day or a year therefore they aren't scared of a piddly four degree increase in the average global surface temperature! They don't understand how averages are worked out or that there is a huge difference in terms of human comfort (or lack of) between a top of 43 degrees Celsius and a top of 53 degrees Celsius. (Comments are archived with the WUWT article here.)
December 16, 2013 at 1:04 pm
My area experiences a 100-degree annual temperature swing. The notion 4 degrees would have any noticeable effect on vegetation is laughable.
RHS says "those plants won't notice a thing!":
December 16, 2013 at 1:08 pm
I’m with talldave2, being in Denver, we’ve experience lows last week of minus 10 and an expected high today of 60. With a swing of 70 degrees in about 7 days, it is hard to imagine we’d notice a thing with a 4 degree difference.
nicholas tesdorf says "scientists don't know nuffin'":
December 16, 2013 at 1:08 pmActually, nicholas, the IPCC "says" 20% of our CO2 pollution stays in the air for many thousands of years.
German and Austrian taxpayers who are funding this sort of alarmist nonsense from the Potsdam Institute for Climate Impact Research in Germany and the International Institute for Applied Systems Analysis in Austria should feel savagely aggrieved. One glance at the chart of peer reviewed literature would tell one that CO2 remains in the atmosphere for less than 10 years, not 100 years. The IPCC might as well claim 1,000 years and make a real meal of it all.
December 16, 2013 at 1:26 pmUmm, the warmer world means that there is more drought and fires and plants will die and burn and give up CO2 making it warmer still.
A warmer world will create drought??? I stopped reading at that point.
Rob Potter is another one who commits the logical fallacy of personal incredulity and thinks that "scientists don't know nuffin'". He says that he doesn't like the definition of residence time of carbon in vegetation. He's not interested in that. In fact he doesn't even believe that droughts will get worse as the world heats up. He thinks that all the moisture in the air will stop droughts from happening. Silly Rob doesn't know that we will have more droughts and more floods, sometimes in the same place at the same time. I suppose he thinks he knows all this because he thinks that scientists (who don't know nuffin') told him so.
December 16, 2013 at 1:29 pm
Wait a minute, all the discussion of residence time has referred to CO2 in the atmosphere, not plants. In the very first sentence they have re-defined this as “the length of time carbon remains in vegetation during the global carbon cycle – known as ‘residence time’ -”. This is a bait and switch as non-one is concerned with residence time in plants, only in the atmosphere.
And even more junk when they use 4 degrees as the end of the world scenario, but the effect on plants is the supposed widespread drought that this 4 degree rise creates. Really? Such a rise in temperature is going to remove water vapour from the atmosphere? Despite the fact that such an increase would release a great deal of frozen water from glaciers and get it into liquid form where it will evaporate easier? The simplistic idea that warmer equals drier is the complete opposite of the basic CAGW meme that CO2 effect in the atmosphere is amplified by the increased water vapour which it causes.
No, pile of junk from the first to the last. No basis in physical or biological fact (as the people who have pointed out how well plants grow at a wide range of temperatures have already pointed out).
RockyRoad says the Earth system has no limits. All the world is infinite.
December 16, 2013 at 1:50 pm
There’s somehow a limit to how many trees grow, or how much grass the earth supports, or how many newspapers end up in landfills, or….
These guys are lying like a lot of other politicians I’m familiar with.
Richard M says it's not going to get any warmer:
December 16, 2013 at 2:31 pm
It isn’t going to warm anywhere near 4° which makes the entire paper a big s0-what. We will likely experience two cool PDOs this century and a solar minimum of some unknown degree. Chances are it won’t be any warmer in 2100 then it is right now, and it could be cooler.
james griffin keeps referring to "previous Holocenes". He used to have six of them IIRC. This time he's reduced it to five and says:
December 16, 2013 at 3:16 pm
At least one of the previous five Holocene’s had temperatures 5C higher than today….as soon as one sees the words “climate models” we know it is a waste of time
RicHard. says blithely, ignoring the references to boreal forest fires and mid-latitude droughts :
December 16, 2013 at 3:21 pm
4 degrees is meaningless in agriculture. Each country has its own indiginous plants that are well able to withstand this increase. It is when you plant non indiginous plants that there could be a problem.
bob prudhomme doesn't think that humans were able to breathe until well into the twentieth century at the earliest and says (excerpt):
December 16, 2013 at 3:41 pm
If co2 drops to 200 to 300 ppm then human beings quit breathing .
Arno Arrak is a physics denier and says:
December 16, 2013 at 4:09 pm
Regarding the carbon residence time. It is actually irrelevant because carbon dioxide is not warming the world
Archer, D. (2005), Fate of fossil fuel CO2 in geologic time, J. Geophys. Res., 110, C09S05, doi:10.1029/2004JC002625
Andrew D. Friend, Wolfgang Lucht, Tim T. Rademacher, Rozenn Keribin, Richard Betts, Patricia Cadule, Philippe Ciais, Douglas B. Clark, Rutger Dankers, Pete D. Falloon, Akihiko Ito, Ron Kahana, Axel Kleidon, Mark R. Lomas, Kazuya Nishina, Sebastian Ostberg, Ryan Pavlick, Philippe Peylin, Sibyll Schaphoff, Nicolas Vuichard, Lila Warszawski, Andy Wiltshire, and F. Ian Woodward. Carbon residence time dominates uncertainty in terrestrial vegetation responses to future climate and atmospheric CO2. PNAS, December 16, 2013 DOI: 10.1073/pnas.1222477110