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
One day someone will write a paper that doesn’t say wtte “the demand for further research remains very high”
First sentence: “update” should be “uptake”
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
Caesar, nos es quoque plenus of carbo carbonis. Plumbum nos ut vomitorium.
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.
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.
” 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.
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.
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?
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.
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.
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.
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.
“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!
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.
Whatever. None of this will stop the coming ice age.
And since there is no evidence of an increase in extreme weather, this study and its conclusions is inconsequential.
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 ….
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/
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.
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.
2kevin says: August 15, 2013 at 9:53 pm
Caesar, nos es quoque plenus of carbo carbonis. Plumbum nos ut vomitorium.
plenus of ?
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.
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…
Lady Life;
Here’s a little Brain Bounce for you: in North America, earthworms are an invasive, alien species. They were introduced by Europeans.