Vicious Carbon Cycles

From the Helmholtz Association

Extreme weather, climate and the carbon cycle

Extreme weather and climate events like storms, heavy precipitation and droughts and heat waves prevent the uptake of 3 giga-tonnes of carbon by the global vegetation. A team of scientists under the lead of Markus Reichstein, Director of the Max Planck Institute for Biogeochemistry in Jena, Germany, investigated the effect of extremes on the carbon cycle from the terrestrial ecosystem perspective for the first time.

In the current issue of Nature (14th of August 2013), they use Earth observation methods and numerical models to show that especially extreme droughts lead to a strong reduction in the carbon sequestration of forests, grass- and croplands. This reduction in the regional and global carbon uptake has the potential to influence the global climate. Especially large scale events like the heat wave in western and southern Europe in the year 2003 provide the evidence that such extremes events have a much stronger and long lasting impact on the carbon cycle than expected so far.

One part of the question is the response of arable ecosystems: plants take up carbondioxide, soils are an important storage for the carbon produced by plants, which they release driven by increasing temperature. However, in the case of croplands we observe a complex interplay of these natural processes with the human management either increasing or reducing the impacts of an event. “In general the timing of an event in the course of the development of crops clearly influences the magnitude of the impact on the carbon cycle. Extreme temperature in spring can foster growth, prevent pollination, or have no effect at all, depending on when they appear in the cropping cycle and the type of crop” says Martin Wattenbach from the GFZ German Research Centre for Geosciences, who contributed to this part of the study. “Rice yields are reduced when temperatures rise above 37°C, but only in the short period of pollination in spring”

It is possible for farmers to mitigate extremes like droughts and heat waves by, for example, irrigation. However, they are limited by the amount of water available at the time of the event and their technical resources. Since information on spatial and temporal patterns of management practise such as irrigation and annual crop distribution during an extreme event are largely unknown, the demand for further research remains very high. In addition to this part of the carbon cycle playing a relevant role in climate, the long term supply with agricultural produce may also be affected.

###

Reichstein, M., Bahn, M., Ciais, P., Frank, D., Mahecha, M.D., Seneviratne, S. I., Zscheischler, J., Beer, C., Buchmann, N., Frank, D.C., Papale, D., Rammig, A., Smith, P., Thonicke, K., van der Velde, M., Vicca, S., Walz, A., and Wattenbach, M. (2013): “Climate extremes and the carbon cycle”, Nature. doi: 10.1038/nature12350, 14.08.2013

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SMCG
August 15, 2013 9:45 pm

One day someone will write a paper that doesn’t say wtte “the demand for further research remains very high”

Lance Wallace
August 15, 2013 9:47 pm

First sentence: “update” should be “uptake”

CRS, DrPH
August 15, 2013 9:52 pm

Thanks, Anthony! Gee, plants don’t take up as much carbon dioxide during a drought….whoulda thunk? As far as irrigation, my mentor, Dr. John “Jack” Sheaffer, developed an excellent wastewater treatment/land application process many years ago & even has a letter of commendation from then-President Richard Nixon! See this article for more info: http://news.uchicago.edu/article/2010/03/22/hammond-project-turn-waste-wealth

2kevin
August 15, 2013 9:53 pm

Caesar, nos es quoque plenus of carbo carbonis. Plumbum nos ut vomitorium.

Lewis P Buckingham
August 15, 2013 10:04 pm

As I understand the theory, global warming leads to greater sea area and heating of the upper 700 metres of the ocean.
This in turn will increase the biomass of plankton, the efficient users of CO2.
So one would expect that the CO2 to be increasingly taken up in such a global warming state.
Perhaps these researchers need more funds to actually work this out.

FrankK
August 15, 2013 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.

Greg
August 15, 2013 10:19 pm

” Since information on spatial and temporal patterns of management practise such as irrigation and annual crop distribution during an extreme event are largely unknown, the demand for further research remains very high. ”
IOW, this study draws could-be/may-be conclusions from totally insufficient information…. blah, blah, global warming… please give generously.

Lady Life Grows (Esther Cook)
August 15, 2013 10:25 pm

Actually, I have concluded that there really is climate change going on, and it truly is dangerous. It is drought caused by human farming that bares (exposes) the soil. It is mitigated by animal herd management–and by carbon dioxide, which helps plants recover the territory.
When land is stripped by non-Organic farming methods, especially those which poison the soil, there is less life (earthworms and so on) in the soil, and I believe that it is actually the loss of that soil-sequestered carbon which has led to the measured rise in atmospheric CO2.
The solution is Permaculture. Recent discoveries show how Desert land can be reclaimed. You can also find some interesting things from http://www.originalsonicbloom.com
You can also read Michael Pollan’s “The Omnivore’s Dilemma” or any of Joel Salatin’s books on agriculture that heals the land.

Leo Morgan
August 15, 2013 10:30 pm

I’ve long wondered how much carbon is captured by bacteria, contributing to sediment at the bottom of lakes and oceans, and similarly how much is captured by fish excrement, fish corpse, dead seaweeds, phytoplankton and algae falling into sediment?
Surely these capture methods will increase as carbon increases and the planet warms?
Does anyone have a link to an article that discusses these in terms accessible to an intelligent layman?

Henry Clark
August 15, 2013 10:34 pm

Regarding the implicit theme related to this article of (incorrectly) implying global warming will mean more extreme droughts on average:
As counterintuitive as it might superficially seem, for the world as a whole, there is *less* drought during times of global warming and more drought during times of global *cooling.* That is because the ocean surface changes temperature as well as the land, and global warmth means more evaporation from oceans aiding precipitation over land. In fact, the world was far more arid than now with far more desert area (including polar deserts: cold but with low precipitation) during the cold Last Glacial Maximum, as strikingly seen in the following color-coded map comparison:
http://upload.wikimedia.org/wikipedia/commons/0/08/Aridity_ice_age_vs_early_holocene_vs_modern.jpg
(which is from the illustrations and data at http://www.esd.ornl.gov/projects/qen/nerc.html )
Of course, some local trends go the opposite direction of global trends sometimes, but, overall, on average, if the world has more droughts in the future due to climate change, that would be from global cooling, not global warming.
What global warming has occurred since the Little Ice Age has overall increased (not decreased) vegetation, simultaneous with carbon fertilization and with growing seasons in many regions being less shortened by frost damage.

WJohn
August 15, 2013 10:41 pm

Préci:_ Plants do not do so well when they are not watered.
Some people help their plants by watering them.
No one has counted how many people water their plants.
I want to travel the world, especially the nice warm bits and count these people.
Please give generously.

August 15, 2013 11:10 pm

Wow. Droughts suppress crop yields and irrigation mitigates affects of droughts. I bet farmers all over the world are shocked by this. Shocked I say! Up until now, the design and implementation of irrigation systems had become a multi-billion dollar industry based solely on rich farmers who bought them so they could generate rainbows on demand.

August 15, 2013 11:15 pm

I notice also that they studied the affects of untimely heat on crop production. Had they studied the effects of untimely frost on crop production, they’d have come up with much larger numbers. Again, farmers would have been completely surprises by this, they’ve been engaged in selective breeding of plant species with shorter growing seasons and higher resistance to untimely frost for the last few centuries because they were bored and had nothing else to do.

August 15, 2013 11:21 pm

“It is possible for farmers to mitigate extremes like droughts and heat waves by, for example, irrigation. However, they are limited by the amount of water available at the time of the event and their technical resources.”
Genius!

WJohn
August 15, 2013 11:24 pm

Next week :- The arboreal habits of Ursus Aamericanus.
Research funding is needed for:-
a) A big thesaurus. No one will publish without impressive ten dollar words
b) A calculator for expediting numerical methods (big sums)
c) A shovel
d) to z) Others unspecified but costing upwards of several hundred thousand dollars.

Richard111
August 15, 2013 11:26 pm

Whatever. None of this will stop the coming ice age.

Chris Schoneveld
August 15, 2013 11:37 pm

And since there is no evidence of an increase in extreme weather, this study and its conclusions is inconsequential.

JJ
August 15, 2013 11:41 pm

In the current issue of Nature (14th of August 2013), they use Earth observation methods and numerical models to show that especially extreme droughts lead to a strong reduction in the carbon sequestration of forests, grass- and croplands. This reduction in the regional and global carbon uptake has the potential to influence the global climate.
I love it how, in the face of nearly two decades of model-invalidating flat temperatures, the ‘global warming’ machine keeps spitting out stories of newly discovered positive feedbacks. These folks need to start explaining why actual the temps are lower than their model predictions, not why their model predictions should have been higher ….

Tom Harley
August 15, 2013 11:49 pm

The CSIRO are blowing up a storm once again with the ‘global warming agenda’, oops, carbon pollution agenda, scaring marine mammals half to death. I would have thought the extra CO2 would be a boon to mammals such as dugong: http://pindanpost.com/2013/08/16/scaring-the-dugongs-silly/

August 15, 2013 11:56 pm

What is a climate “event”? Wouldn’t that take some time to occur? How would you know when it started? A change in the…….weather? I stopped taking this latest Planck in the Platitudeform seriously at that very first assertion.

dp
August 15, 2013 11:57 pm

I’m pretty sure I read on this site recently that abundance of CO2 has led to the reversal of desertification around the world. Good thing, too, or this post would be worrying. On the other hand I’ll bet a couple hundred feet of packed snow would be a bad thing too – worse, in fact than warming. Watt’s a skeptic to do? Is anyone really looking forward to a colder world where global temperatures are reversed to the 1880’s level?
Meanwhile I saw several potted fuchsias and one rangy hydrangea thumbing a ride up Snoqualmie Pass today – clearly looking to escape the UHI in Issaquah. An image fit for Cartoons by Josh.

Mike McMillan
August 16, 2013 12:06 am

2kevin says: August 15, 2013 at 9:53 pm
Caesar, nos es quoque plenus of carbo carbonis. Plumbum nos ut vomitorium.

plenus of ?

Ian W
August 16, 2013 12:27 am

Max Planck must be spinning in his grave, and the “Max Planck Institute” is not normally known for such facile research. As WJohn says August 15, 2013 at 10:41 pm it is an exercise in stating the obvious, not only obvious but information known by most first grade pupils, using unnecessarily orotund report language.
Such as obvious statements:-
Plants do not grow well when they are not watered, which becomes:
“Earth observation methods and numerical models to show that especially extreme droughts lead to a strong reduction in the carbon sequestration of forests, grass- and croplands.”
and
If you irrigate plants in a drought they grow better, which becomes:
It is possible for farmers to mitigate extremes like droughts and heat waves by, for example, irrigation.”
The extent to which the obvious is repeatedly restated but obfuscated makes me wonder whether this is actually a ponderous joke being played on the funding politicians and the journal Nature. It is almost as though there is a bet running at the Max Planck Institute on how easily these politicians can be duped out of funds and journals into publishing, just by using the green CAGW/Climate Change ‘hot-button’ words buried in report language. These statements of the obvious are then repeated in ‘hushed tones’ by the once proud but now disappointingly gullible journals.

August 16, 2013 1:15 am

Meanwhile, deserts are greening thanks to more CO2 that makes that plants need less stomata and thus lose less water vapour. And the global uptake of CO2 by the biosphere only increased over the past decade…
Again a study which has its origin in failing models…

August 16, 2013 1:27 am

Lady Life;
Here’s a little Brain Bounce for you: in North America, earthworms are an invasive, alien species. They were introduced by Europeans.

DirkH
August 16, 2013 1:29 am

” the demand for further research remains very high. ”
Oh goody, the leeches have DEMANDS now.

August 16, 2013 1:30 am

Ferdinand;
Yes, it will be amusing, should I last so long, to read in a few decades how humanity greened and rescued the biosphere in spite of itself by emitting CO2 that it didn’t want to. Hyuk-hyuk, he said!

August 16, 2013 2:03 am

Not long ago I read a paper – report (very alarmist) from one of the employees of Dutch institute KNMI (sorry I can not quickly find the link) that yes, the number of extreme events in the World – global, has increased but … no drought.
Increased frequent of extreme precipitation.
… but if the increased number of droughts …
I remember only two papers:
Terrestrial Gross Carbon Dioxide Uptake: Global Distribution and Covariation with Climate, Beer et al. 2010. (http://www.sciencemag.org/content/329/5993/834.abstract):
“Most likely, the association of GPP and climate in process-oriented models can be improved by including negative feedback mechanisms (eg, adaptation) that might stabilize the systems.
The ecological role of climate extremes: current understanding and future prospects, Smith, 2011. (http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2745.2011.01833.x/pdf):
“Finally, with a long-term field experiment where statistically extreme drought events were applied to constructed European grassland communities for five consecutive years, (Jentsch et al. 2011) show a lack of large effects for the majority of the 32 response parameters measured. For example, above- and below-ground productivity remained unchanged across all years of the study …”

August 16, 2013 2:18 am

I will not refuse myself the pleasure of cite:
“Managing the risks of extreme events and disasters to advance climate change adaptation” (www.ipcc-wg2.gov/SREX/images/uploads/SREX-SPMbrochure_FINAL.pdf), 2012.:
“There is medium confidence that some regions of the world have experienced more intense and longer droughts, in particular in southern Europe and West Africa, but in some regions droughts have become less frequent, less intense, or shorter, for example, in central North America and northwestern Australia.
“Furthermore, there is low agreement in this evidence, and thus overall low confidence at the global scale regarding even the sign of these changes.”

Jimbo
August 16, 2013 2:18 am

In the current issue of Nature (14th of August 2013), they use Earth observation methods and numerical models to show that especially extreme droughts lead to a strong reduction in the carbon sequestration of forests, grass- and croplands.

They say ‘extreme droughts’ which sounds a bit obvious. Just look at the middle of the Sahara. Just this year we had papers showing how arid areas are becoming greener and arable land becoming more productive due to co2 fertilisation [HERE]. I also understand that more co2 in the atmosphere makes vegetation more drought resistant. It looks like this paper has been published to keep the funds flowing in the right direction in the face of contradictory observations.
As a footnote see one Hartmut Grassl, the a former “director of the Max Planck Institute for Meteorology in Hamburg until 2005” and “once director of the UN World Climate Program in Geneva from 1994 to 1999”. He can now be found on the Board of Trustees of the large re-insurer Munich Re. You can also find the other German alarmists at Potsdam Institute for Climate Impact Research — PIK in bed with the insurance industry. Munich Re has been fanning climate alarmism since the 1970s I believe.

wayne Job
August 16, 2013 3:03 am

Gobblygook looking for a hand out, these people need to get a real job. Maybe tending pot plants in some ones productive office and researching their reaction to water, CO2 and the office temperature, you never know they might learn some thing.

Keith
August 16, 2013 3:09 am

Right at the beginning, they state “Extreme weather and climate events”, then state merely weather events “like storms, heavy precipitation and droughts and heat waves”.
Now a climate ‘event’ might be something like Yellowstone, Toba and Laki going kerblooey all at once, but calling a heat wave or a downpour a climate-anything is ridiculous. Still, gotta keep that junk-science funding handle turning…

Alan the Brit
August 16, 2013 3:34 am

“Since information on spatial and temporal patterns of management practise such as irrigation and annual crop distribution during an extreme event are largely unknown, the demand for further research remains very high.”
I translate: “largely unknown” = “Not a frigging clue”!
Haven’t read the latest musings from UK’s Wet Office, but there last projections of portentous BS puter modelling, went something like this……”some areas will have more rainfall, some area will have less rainfall, some areas will have more drought, some areas will have less drought, some areas will have higher temperatures, some areas will have lower temperatures”. It was embarrassing reading to be frank.

lurker, passing through laughing
August 16, 2013 3:49 am

The vast majority of the carbon cycle takes place in bodies of water, like oceans, where droughts don’t really have much impact, if I recall.

Eric H.
August 16, 2013 3:59 am

So…increased atmospheric CO2=climate change=more extreme events=less CO2 uptake for vegetation=more CO2=more climate change…OMG, the feedback mechanism is more positive than we estimated!!!! (do I really need a sarc tag?)

Bob
August 16, 2013 4:16 am

Mike Bromley the Kurd says:
August 15, 2013 at 11:56 pm
What is a climate “event”? Wouldn’t that take some time to occur? How would you know when it started? A change in the…….weather? I stopped taking this latest Planck in the Platitudeform seriously at that very first assertion.
——————————————————————————–
We had a big thunderstorm with high wind and hail last Saturday. Does that count?
Biogeochemistry—impressive. Now they just need to add physics to the title. “physicalbiogeochemistry” or “biogeochemicalphysics” would make it sound much more impressive.
I’ve heard rumors that we had droughts and the like long before we had an Environment and Climate.

Richard M
August 16, 2013 4:17 am

Since irrigation is a man-made process this study sounds like humans help reduce the impact of completely natural droughts. That won’t go over well with the anti-humanists.

Ian W
August 16, 2013 4:23 am

Stop taking this paper so seriously. As I said earlier http://wattsupwiththat.com/2013/08/15/vicious-carbon-cycles/#comment-1391721 this is a joke played by the researchers and everyone is falling for it including their funders and the journals. Scatter some hot-button warmist phrases through a report that states the blindingly obvious and get funded for it AND published.
Scamming the scammers brilliant.

CodeTech
August 16, 2013 5:18 am

Repeated use of the word “EXTREME!”… check
Use of the phrase “more than expected”… check

evidence that such extremes events have a much stronger and long lasting impact on the carbon cycle than expected so far

Vague, indefinite terms… check

human management either increasing or reducing the impacts of an event

Statement of the blatantly obvious… CHECK

It is possible for farmers to mitigate extremes like droughts and heat waves by, for example, irrigation. However, they are limited by the amount of water available at the time of the event and their technical resources.

Completely one-sided presentation of research… CHECK and DOUBLE CHECK

Extreme weather and climate events like storms, heavy precipitation and droughts and heat waves prevent the uptake of 3 giga-tonnes of carbon by the global vegetation.

(Whereas, of course, optimal conditions experienced at non-extreme locations could easily enhance the uptake by 3 gigatonnes or more)
Hand out for more money… Triple Check, and Mate!

the demand for further research remains very high

Yep, it’s “climate science” all right.

Kon Dealer
August 16, 2013 5:28 am

So how does this “paper” account for the increased annual variation in CO2 levels measured at Hawaii?
These Northern summer/winter cyclical changes indicate greater activity in the biosphere, not less, as this latest alarmist excretion would like us to believe.

izen
August 16, 2013 5:57 am

@- Leo Morgan
“I’ve long wondered how much carbon is captured by bacteria, contributing to sediment at the bottom of lakes and oceans, and similarly how much is captured by fish excrement, fish corpse, dead seaweeds, phytoplankton and algae falling into sediment?”
These are the usual ways in which carbon on the active biological cycle is sequestered into the long term geological cycle. It has of course been the subject of extensive study, and the rate at which it happens is recorded rather neatly in any sediment core you take from lakes and oceans.
@- “Surely these capture methods will increase as carbon increases and the planet warms?
Does anyone have a link to an article that discusses these in terms accessible to an intelligent layman?”
Well unless you have a conspiracy theory which causes you to reject the most comprehensive compilation of scientific knowledge on this subject I would suggest starting with –
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch7s7-3-4.html
However if you find that assumes more intelligence than you think a layman can apply to the subject, or you arbitrarily reject it for non-scientific ideological reasons then try –
http://www1.whoi.edu/62987_ocean.pdf

Gail Combs
August 16, 2013 6:04 am

Lady Life Grows (Esther Cook) says:
August 15, 2013 at 10:25 pm
Actually, I have concluded that there really is climate change going on, and it truly is dangerous. It is drought caused by human farming that bares (exposes) the soil. It is mitigated by animal herd management….
>>>>>>>>>>>>>>>>>>>>>
I agree and my farm, once a rented tobacco field and now pasture is an example. The farm used to have the richest soil in the county according to the Ag extension agent and the old soil survey. There was over two feet of loam now all washed into the sea and only the clay subsoil remained. The farm was barely able to support weeds when I purchased it.
Good soil conservation practices are well known but they cost quite a bit of money so they are not used on rented fields or on corporate owned farms that are only bought and sold for the purpose of making a profit. Betting the farm: As world population expands, the demand for arable land should soar. At least that’s what George Soros, Lord Rothschild, and other investors believe.
Farm families who have owned their farms for generations are much more likely to look at their land as a generational investment to be carefully taken care of.

Gary Pearse
August 16, 2013 6:45 am

I would have thought carbonation of rain water while in the air would have increased the removal of carbon D from the atmosphere.

michael hart
August 16, 2013 6:52 am

Leo Morgan, you are already more of a scientist, and less of a layman, than Izen is. You are able to ask questions.

Gail Combs
August 16, 2013 6:52 am

dp says: @ August 15, 2013 at 11:57 pm
I’m pretty sure I read on this site recently that abundance of CO2 has led to the reversal of desertification around the world….
>>>>>>>>>>>>>>>>>
Yes, more CO2 means C3 plants do not have to have the stomata open as wide or as long and therefore they do not suffer as much water loss. A principle response of C3 plants to increasing concentrations of atmospheric CO2 (CO2) is to reduce transpirational water loss by decreasing stomatal conductance (gs) and simultaneously increase assimilation rates. Via this adaptation, vegetation has the ability to alter hydrology and climate.
CO2 increase also does the same for C4 plants. This is a very interesting study/survey of the literature on C4 Plants Adaptation to High Levels of CO2 and to Drought Environments It also touches on C3 plants. It makes a number of good observations although it is from the point of view:
“..Increase in global average temperatures would further result in drastic shifts in the annual precipitation with a 20% reduction per year, and about 20% loss in soil moisture (Schiermeier, 2008). Regarding plants, higher atmospheric CO2 levels tend to reduce stomatal conductance and transpiration, thereby lowering latent heat loss and causing higher leaf temperatures (Bernacchi et al., 2007). Thus, in the future, plants will likely experience increases in acute heat and drought stress, which can impact ecosystem productivity (Cias et al., 2005) and biodiversity (Thomas et al., 2004)….”
I guess these botanists never ever heard of evaporation rate and its correlation to temperature.

C4 Plants Adaptation to High Levels of CO2 and to Drought Environments
….The C4 photosynthesis is an adaptation of the C3 pathway that overcomes the limitation of the photorespiration, improving photosynthetic efficiency and minimizing the water loss in hot, dry environments… Most C4 plants are native to the tropics and warm temperate zones with high light intensity and high temperature. Under these conditions, C4 plants exhibit higher photosynthetic and growth rates due to gains in the water, carbon and nitrogen efficiency uses<….
Some of the world’s most productive crops and pasture, such as maize (Zea mays), sugar cane (Saccharum officinarum), sorghum (Sorghum bicolor), amaranth, paspalums (Paspalum notatum and P. urvillei), bermudagrass (Cynodon dactylon), blue grama (Bouteloua gracilis) and rhodes grass (Chloris gayana) are C4 plants. In addition, the most troublesome weeds like nutgrass, crabgrass and barnyard, are also C4 species. Although C4 plants represent only a small portion of the world ́s plant species, accounting for only 3 % of the vascular plants, they contribute about 20% to the global primary productivity because of highly productive C4-grass-lands (Ehleringer et al., 1997)….
….This is the reason why at temperatures below ca. 25–28 oC, C4 photosynthesis is less efficient than C3 photosynthesis under light-limiting conditions. It is interesting to note, that while global distribution of C4 grasses is positively correlated with growing season temperature, the geographic distribution of the different C4 subtypes is strongly correlated with rainfall (Ghannoum et al., 2011). On the contrary, C4 plants are rare to absent in cold environments. Although there are examples of plants with C4 metabolisms that show cold adaptation, they still require warm periods during the day in order to exist in cold habitats….
High CO2 aggravates nitrogen limitations and in doing so may favor C4 species, which have greater photosynthetic nitrogen use efficiency (Sage & Kubien, 2003). On the other hand, elevated CO2 can also increase water use efficiency, in part by decreasing stomatal conductance and transpiration (Ainsworth et al., 2002). The irradiance is also a paramount factor; enhanced photosynthesis under elevated CO2 conditions was observed in C4 plants grown under high irradiance, while there was not much response when grown under low irradiance (Ghannoum et al., 2000).
Another aspect of plant metabolism which may vary under exposure to increased CO2 is the respiration. As highlighted by Reddy and colleagues (2010) in C4 plants little is known about the impact of elevated CO2 on the respiratory rates, which are reduced in C3 species and thus, probably contributing to increase biomass yield…
General effects of elevated CO2 on photosynthetic heat tolerance were recently investigated in a comparative study including C3 and C4 species and they can be summarized as follows:
(i) in C3 species, elevated CO2 typically increases heat tolerance of photosynthesis, except for plants grown at supra-optimal growing temperature, then elevated CO2 may provide no benefit or even decrease photosynthesis;
(ii) in C4 species, elevated CO2 frequently decreases photosynthetic thermotolerance, at near-optimal growing temperature as well as supra-optimal growing temperature (Wang et al. 2008; Hamilton et al., 2008).
Although both C3 and C4 plants experience reductions of similar magnitude in stomatal conductance with increasing CO2 (e.g., 20%–50% with a doubling of CO2) (Sage, 1994; Reich et al., 2001; Wang et al., 2008), the lower stomatal conductance of C4 plants at any given CO2 level means lower average transpiration and higher leaf temperatures in C4 plants, which may increase heat related damage in C4 plants compared with C3 plants in the same habitat. On the other hand, elevated CO2 increases leaf size (Morison & Lawlor, 1999), and this should increase leaf temperatures during heat stress more in C3 than C4 species, given the greater average stimulation of growth in elevated CO2 in C3 species (Poorter & Navas, 2003)….

The above was written from the point same point of view as the paper under discussion and the authors try real hard to show ‘Global Warming’ will injure plants and thus the insertion of the drought resistance/water conservation from elevated CO2 “…means lower average transpiration and higher leaf temperatures in C4 plants, which may increase heat related damage…”
Another interesting tidbit:
Studies have revealed that about 10 percent of the moisture found in the atmosphere is released by plants through transpiration. The remaining 90 percent is mainly supplied by evaporation from oceans, seas, and other bodies of water (lakes, rivers, streams).

artw
August 16, 2013 6:54 am

WJohn says:
August 15, 2013 at 10:41 pm
From: Institute for Climate Disruption Research
To: WJohn
Re: Grant request
Sir,
Your request for funding to travel and count people who water their plants is denied. The very notion of doing field work, collecting data, is counter to the principles of this department. Collection of field data just isn’t done!
However, should you wish this department to reconsider your research request, please submit a draft Abstract and Conclusion of your proposed paper, in compliance with the Institute’s Research Mandates, Section 2, paragraph 3. The Institute takes it’s responsibilities very seriously, as subparagraph 3b states “The Institute shall review the Abstract and Conclusions of any proposed research prior the start of such research.” As you know, the Institute cannot allow any research to be done which might even hint at a suggestion that global warming, climate change or climate disruption has any other cause other than anthropomorphic. Why this would be counter to the teachings of High Priest Gore and Chief Acolyte Mann.
Your options for research are limited to 1) literature review, in the mode of Cook, et al (the Department really believes that this is the future of all research, so much easier to get the results desired), or 2) employment of a suitable model*, in which all inputs variables, feedbacks and outputs can be tightly controlled (ref. Research Mandates, Section 4, paragraph 4, subparagraphs 2-6).
Compliance Officer
Dept of Climate Disruption Research
* Should you chose to employ a model, and insist on fieldwork as part of this research, the Compliance Office shall assign, in accordance with Research Guidelines Section 4, paragraph 4, subparagraph 8, a Compliance Officer to accompany said model to the field, to ensure the correct data is sent back to you at the Institute, as researchers are not permitted to do field work.

artw
August 16, 2013 6:59 am

artw says:
August 16, 2013 at 6:54 am
Forgot the /sarc tag

Tim Clark
August 16, 2013 7:03 am

Well, at its best, this paper is just another pathetic data extrapolation leading to dire consequences for mankind causing me irritable climate syndrome.

Gail Combs
August 16, 2013 7:07 am

Bob says: @ August 16, 2013 at 4:16 am
What is a climate “event”?
>>>>>>>>>>>>>>>>>
A glacial an interglacial, an ice age, a Bond event, a Dansgaard–Oeschger event, a Heinrich event…
Everything the warmists talk of is just weather.

Gail Combs
August 16, 2013 7:10 am

CodeTech says: @ August 16, 2013 at 5:18 am
Repeated use of the word “EXTREME!”… check….
>>>>>>>>>>>>>>>>>>
ROTFLMAO, I wonder if the Warmist Journals and ‘Pal reviewers’ use the same check list.

u.k.(us)
August 16, 2013 7:11 am

Brian H says:
August 16, 2013 at 1:27 am
Lady Life;
Here’s a little Brain Bounce for you: in North America, earthworms are an invasive, alien species. They were introduced by Europeans.
======
Not sure it is that simple?
Per:
http://www.inhs.uiuc.edu/~mjwetzel/IllinoisEarthworms.html
“Introduction. Reynolds and Wetzel (2004) reported 161 species of earthworms representing 37 genera in 10 families known to occur in North America north of Mexico; of these, 45 are considered introduced (Reynolds and Wetzel 2004). In a recent update of that 2004 publication, Reynolds and Wetzel (2008) expanded their scope of North American earthworm distributions to include Mexico, Puerto Rico, Hawaii, and Bermuda. This recent update included 253 species representing 59 genera in 10 families; of these, 67 are considered to be introductions. There are at least 14 introduced species in North America that are known only from greenhouses and other indoor cultures in one or more states from which they have been reported (but it is important to emphasize that some of these species have also been reported in ‘nature’, particularly in some of the more southern/warmer areas of the continent). “

mitigatedsceptic
August 16, 2013 7:19 am

So let’s just ask for more money for research?
I have yet to read an alarmist paper that is not littered with hints and outright demands for money.
It’s like going through a market in the East followed by begging children; except these are not children; they are informed adults who know when to jump onto a passing bandwagon. They are real scary because they are so adept at fleecing us.

kadaka (KD Knoebel)
August 16, 2013 7:27 am

From izen to Leo Morgan on August 16, 2013 at 5:57 am (bold added):

Well unless you have a conspiracy theory which causes you to reject the most comprehensive compilation of scientific knowledge on this subject I would suggest starting with –
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch7s7-3-4.html

Heh.
Please see this: IPCC AR4 also gets a failing grade on 21 chapters
Based on a citizen auditing of IPCC AR4 sources, 21 out of 44 chapters have 59% or less peer-reviewed sources. This volunteer effort arose due to proven reports of “grey literature” being used that was cited as authoritative scientific facts, but included things like (see article for links) “… press releases, newspaper and magazine clippings, working papers, student theses, discussion papers, and literature published by green advocacy groups.
Working group 3, Chapter 4 was the lowest, had only 15% peer-reviewed sources.
However, you are incredibly lucky, as you were referenced to WG1, Ch7, which was the best of all at 96% peer-reviewed sources. You may freely assume the references were deliberately chosen to slant the results for (C)AGW-pushing purposes, as is well known, but you have better odds of finding something accurate and possibly current and usable than the rest of the IPCC report.
Have fun.

GlynnMhor
August 16, 2013 7:49 am

Esther Cook writes of: “… books on agriculture that heals the land.”
Agriculture does quite the opposite.
There is no more devastating activity for destroying ecosystems than farming.
Farming strips the land of all natural growth, natural habitats, natural animals and plants, and replaces huge areas with invasive species chosen by humans for their utility to humans.

DirkH
August 16, 2013 7:56 am

izen says:
August 16, 2013 at 5:57 am
“Well unless you have a conspiracy theory which causes you to reject the most comprehensive compilation of scientific knowledge on this subject I would suggest starting with –
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch7s7-3-4.html

Izen, are you a Greenpeace member? A WWF bureaucrat? Why do you endorse that compilation of grey literature?

August 16, 2013 8:24 am

Well, the carbon cycle is big (20x current human production) and fast (200gt/yr), but mean? Naah, Carbon is money and we are in a depression. Watch everything grow, watch and learn.
The perturbations they mention push the cycle from k to r selected critters, but the net effect is lunch money in the cycle, as is human production.

bit chilly
August 16, 2013 8:41 am

i would suggest izen is probably just stupid.like many ordinary citizens were in the beginning,for swallowing this guff.
so this latest lot of tripe has the audacity to suggest ,that despite claims that increases in co2 are entirely man made,and increases in temperature man made as a result,there are in fact weather events taking place around the planet every year that alter the level of co2 in the atmosphere naturally ?
who ever would have thought.better not let the IPCC see this paper,they will never get funding again.
it shows how stupid some of these people are when they are using contradictory evidence to support their own failed by observation hypothesis.

izen
August 16, 2013 8:55 am

@- DirkH
“Izen, are you a Greenpeace member? A WWF bureaucrat? Why do you endorse that compilation of grey literature?”
The main ‘grey’ literature in the WG1 scientific part of the report is a quote from Isaac Newton. The rest including the part about the climate carbon cycle is all based on science. If you had read the linked section you would have seen that the references given are NOT grey literature. Presumably you are not that familiar with the work you are criticising and dismissing so ignorantly.

BBould
August 16, 2013 9:59 am

For accuracy – Wikipedia says “Of the 182 taxa of earthworms found in the United States of America and Canada, 60 or almost 33% are invasive species.” Not ALL!

richardscourtney
August 16, 2013 11:36 am

izen:
At August 16, 2013 at 8:55 am you say to DirkH

The main ‘grey’ literature in the WG1 scientific part of the report is a quote from Isaac Newton. The rest including the part about the climate carbon cycle is all based on science. If you had read the linked section you would have seen that the references given are NOT grey literature. Presumably you are not that familiar with the work you are criticising and dismissing so ignorantly.

I cannot speak for DirkH but I am very familiar with that document. I read and studied every word of each its drafts and I have repeatedly studied all of its published version. It provides a one-sided and distorted version of the science which is based on selectivity in its references and distortion of some of its referenced statements.
Simply, it is biased ordure useful as a reference to one ‘side’ of the scientific debate.
However, the NIPCC Report (which I also helped produce) provides the other half of the issues. Taken together the two documents provide a useful overview of the science.
Richard

kadaka (KD Knoebel)
August 16, 2013 11:43 am

From izen on August 16, 2013 at 8:55 am:

The main ‘grey’ literature in the WG1 scientific part of the report is a quote from Isaac Newton.

ref: http://www.noconsensus.org/ipcc-audit/IPCC-report-card.php
WG1
Chapter #-references %non-peer-reviewed
01 264 20%
02 759 5%
03 804 4%
04 257 15%
05 289 4%
06 609 7%
07 869 4%
08 686 6%
09 535 6%
10 545 5%
11 609 11%
Wow, that’s a LOT of non-peer-reviewed references.

The rest including the part about the climate carbon cycle is all based on science. If you had read the linked section you would have seen that the references given are NOT grey literature.

Total WG1 references: 6226
Have you, izen, personally examined and vetted all 6226 references? Or do the titles look sufficiently science-like therefore they must be based in science? Including the personal correspondence?
Homeopathy is based in science. Many things are based in science, like Star Trek. Climate Science is based in science. Is “based in science” an absolute guarantee, no verification required, that something is scientific?

milodonharlani
August 16, 2013 11:54 am

izen says:
August 16, 2013 at 8:55 am
Apparently you have never read IPCC’s own statements on grey literature. IPCC says it can’t function without grey literature. Here’s its statement last year in response to a New Scientist article:
The IPCC has always recognized that non-peer reviewed literature, such as reports from
governments and industry, or national statistics, can be crucial for the IPCC’s assessments.
The appropriate use of such literature expands the breadth and depth of the assessment by
including relevant information. At its previous meeting in Kampala in November 2011, the
Panel agreed to strengthen the rules governing the use of literature from all sources. The
procedures to validate sources of information from non-peer reviewed literature, and to ensure
its quality, were reaffirmed. The procedures specify that the use of non-peer reviewed
literature brings with it an extra responsibility for the author teams. IPCC writing teams were
explicitly required to critically assess and to review the quality and validity of all cited literature.
As in the past, copies of cited information that is not publicly or commercially available must be
held, preferably electronically, in order to be made available to reviewers upon request during
the review of IPCC draft reports. The Panel did not discuss non-peer reviewed literature at its
latest meeting in Geneva.
Here’s a list of some of its rules on grey literature:
http://nofrakkingconsensus.com/2011/01/21/grey-literature-ipcc-insiders-speak-candidly/
IPCC does not practice science but advocacy, in which puffery is not only allowed but encouraged.

D.J. Hawkins
August 16, 2013 4:51 pm

Ferdinand Engelbeen says:
August 16, 2013 at 1:15 am
Meanwhile, deserts are greening thanks to more CO2 that makes that plants need less stomata and thus lose less water vapour. And the global uptake of CO2 by the biosphere only increased over the past decade…
Again a study which has its origin in failing models…

It will be interesting to see what happens over the next decade or two re CO2 vs temperature with respect to deserts greening up. If temperatures drop and CO2 continues to rise, will this offset the more drought-prone conditions one finds in a cooling world, allowing greening to continue? Where would the balance point be?

D.J. Hawkins
August 16, 2013 5:15 pm

kadaka (KD Knoebel) says:
August 16, 2013 at 11:43 am
From izen on August 16, 2013 at 8:55 am:
The main ‘grey’ literature in the WG1 scientific part of the report is a quote from Isaac Newton.
ref: http://www.noconsensus.org/ipcc-audit/IPCC-report-card.php

The really interesting take-away for me is that as the rankings in the table go from “greyest” to “least grey”, it is crystal clear that over time the Working Group reports have become more and more dependent on non-peer reviewed literature.

Janice Moore
August 16, 2013 10:46 pm

@ Art W (6:45AM) — LOL — nice writing and done so well that your “sarc tag” was superfluous. Thanks for the laughs.
********************************************
Well, Ian W, if you say so…. lol (you’re likely right),
but, wow. Given: … Extreme temperature in spring can foster growth, prevent pollination, or have no effect at all, depending …
I think Max Planck would say: “Your “investigations” add 6.55 × 10 *(-27th) to the knowledge of humanity”. Actually, he would have just stared, turned, and walked away in disgust. Then, seeing the sign on the outside of the building snorted, “‘Max Planck Institute?’ You’ve got to be kidding.”
As a result of reading the above article and seeing that sign, Herr Planck made the film below. “I must salvage what remains of my tattered reputation,” he said, “I must tell the world who Max Planck really was.”
First, let me say that I have never been associated with the Max Planck Institute, nor shall I ever be. Their research is garbage and……

Okay, okay, JUST KIDDING (sort of).

Disputin
August 17, 2013 10:31 am

So, as it gets hotter, drier, wetter, etc., etc., the atmospheric concentration goes up. Since we know that warming leads CO2 concentration, that’s nice confirmation.