Guest essay by Eric Worrall
According to a new study, increased transpiration from CO2 engorged plants will return more water vapour to the atmosphere, reducing runoff available to fill reservoirs.
Mid-latitude freshwater availability reduced by projected vegetation responses to climate change
Justin S. Mankin, Richard Seager, Jason E. Smerdon, Benjamin I. Cook & A. Park Williams
Abstract
Read more: https://www.nature.com/articles/s41561-019-0480-x
Plants are expected to generate more global-scale runoff under increasing atmospheric carbon dioxide concentrations through their influence on surface resistance to evapotranspiration. Recent studies using Earth System Models from phase 5 of the Coupled Model Intercomparison Project ostensibly reaffirm this result, further suggesting that plants will ameliorate the dire reductions in water availability projected by other studies that use aridity metrics. Here we complicate this narrative by analysing the change in precipitation partitioning to plants, runoff and storage in multiple Earth system models under both high carbon dioxide concentrations and warming. We show that projected plant responses directly reduce future runoff across vast swaths of North America, Europe and Asia because bulk canopy water demands increase with additional vegetation growth and longer and warmer growing seasons. These runoff declines occur despite increased surface resistance to evapotranspiration and vegetation total water use efficiency, even in regions with increasing or unchanging precipitation. We demonstrate that constraining the large uncertainty in the multimodel ensemble with regional-scale observations of evapotranspiration partitioning strengthens these results. We conclude that terrestrial vegetation plays a large and unresolved role in shaping future regional freshwater availability, one that will not ubiquitously ameliorate future warming-driven surface drying.
Sadly the full study is paywalled, but I think we get the idea; Plants are bad. The study suggests anything which increases transpiration, like anthropogenic CO2 emissions or presumably other changes which lead to increased transpiration, like planting trees, increases stress on the global supply of fresh water.
Of course, there are a few contradictory studies which suggest rainfall decreases if trees are cleared, studies which suggest plant transpiration plays an important positive role in the water cycle, but these studies are based on observations rather than climate projections.
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This is a ridiculous paper. It is arguing the jungles create deserts by using up all the water.
This model-study reads just like a pay-for-play payola effort with one eye on the computer and one eye constantly on the grant inbox. Like all the other Leftist alarm pieces about the effects of CO2 it can safely be ignored.
[MODS] three posts this evening, none showing, what’s up with that.
Just those two words, Models and Projections says it all.
Perhaps they should have added that as there is now less water used by
the plant then this would add to the Greenhouse effect as the water goes back
into the atmosphere.
Meanings.
Model, a electronic device which is programmed to say what the user wants
to hear.
Projections, a guess, what if this was to happen.
As with so much of “”Climate Science”” its complete nonsense.
MJER VK5ELL
More trees bad, less trees good? I believe this is a new version of recent hypothesis that more plant growth will dilute the nutrition per sq/cm in vegetables, and this dilution will be bad, because, um, well, why is it bad? The vegetable will ostensibly have MORE nutrition, because it’s a bigger, healthier fruit or tuber or leaf, or whatever, but you might need to eat one extra bite, of which the plant has generously provided because of it’s enhanced growth, in order to get all the nutrition of the more concentrated pre-CAGW vegetable?
These people in academe are going insane right before our eyes. I’m calling bullshit. The King is naked.
Clearly computers cause climate change.
So now the oceans aren’t going to rise, after all?
As I’ve said before, some papers truly deserve to be paywalled. They don’t deserve to see the light of day and the fools who wish to read them should be made to pay. This seems like a good example.
Wonder what the cost of burying water so it can’t evaporate into cloud formation might be. Water vapor is much more potent green house gas than CO2 from what I hear.
You just need to build a waterproof roof over the ocean to stop evaporation.
“Wonder what the cost of burying water so it can’t evaporate into cloud formation might be. Water vapor is much more potent green house gas than CO2 from what I hear.”
It’s cost effective and already being done for the FRACKING process!!!
Im sure their model is 100% accurate for the entire planet.
Yep, The Amazon and The Congo don’t exist.
https://en.wikipedia.org/wiki/List_of_rivers_by_discharge
My point is that the planet earth is a CLOSED system. That scientists are usually wrong. That next week some other LIMITED study or “model” is going to find the OPPOSITE but “scientists” will ignore the results or claim they are “rethinking” their whatever.
The water on earth stays on earth. A US dollar is only good in the US. Closed systems.*
Scientists reject anything that doesn’t fit their CONSENSUS and preconceptions. I’ll bet you won’t even read ONE of the articles at rsr .org / hydroplate before you dismiss the theory as false. (I reference that because the Hydroplate Theory is contrary to my initial claim that the earth is a closed system. Read until you learn why.)
*What goes around, comes around. Read about the Hydroplate Theory until you understand that. The UNIVERSE is a closed system.
“—————-reduce runoff across vast swathes of north America”. Wow – that will lead to sea levels falling. (sarc
Refilling the aquifers.
Wasn’t there a study that said plants have maximum-rate clocks and that increases in CO2 reduces the number of “breathing holes” and reduces waste transpiration someplace… in the 1980s?
Because I remember it being referenced last damned year in the study that CO2 doesn’t increase plant growth size or by land-area it just makes it easier for them to digest soil effectively and thus produces less waste overall.
Since plants don’t digest soil you clearly remember wrongly.
“Wasn’t there a study that said plants have maximum-rate clocks and that increases in CO2 reduces the number of “breathing holes” and reduces waste transpiration someplace… in the 1980s? Because I remember it being referenced last damned year in the study that CO2 doesn’t increase plant growth size or by land-area it just makes it […]
Since plants don’t digest soil you clearly remember wrongly.”
Uhn… yes the study is correct. The breathing holes are called stomata. And correct, more CO2 causes fewer stomata, and hence less transpiration
All impacts of climate change are bad and all bad things are climate change impacts.
https://tambonthongchai.com/2018/06/21/climate-change-impacts1/
Na na nah nya….my model’s better than your model
[even if the results of my model are ludicrous]
Wherre’s the peer review here?
As an afterthought, how did the planet get on before the start of agriculture and clearing around 10,000 years ago ? No water for anything or anybody ?
Its worse than we thought!
Think of the children!
‘ang on. I thought global warming was going to make it more ‘umid?
And doesn’t more CO2 make plants use water more efficiently? I wish some of these scientists types got their story straight.
Let me pose a question here, more or less to the point; If plants derive all their carbon from atmospheric carbon dioxide, who is releasing all that nasty carbon dioxide into the air? after all, they are supposed to be regurgitating at night the CO2 they took in from the air and could not process; and if plants obtain their nutrients from water that comes into contact with the soil, how does the water know to reject any carbon it comes into contact with in the soil? After all, reading those articles about ancient indians and “terra preta” (black soil) in the Amazon and in Africa, surely the prized black colour comes from carbon? So why does it lose it’s blackness, so that said indians / Africans have to find another patch? Perhaps we don’t understand things quite as much as we think we do.
Then don’t rely on runoff. Rely on desalinization.
CO2 is good for plant life. You can’t possibly deny that, pretending to be a scientist. Oops! Snookered? No, of course not. We just find a hypothetical disadvantage to ‘prove’ that actually CO2 is not good after all.
How about: “Growth will deplete global water supplies.”
The logic displayed in these results only serve to display how models can be driven to prove anything, even illogical conclusions.
Did no one arrive at a testable hypothesis prior to running the model? Were the conclusions not examined for being consistent with real world effects? This appears to be climate scientists/modelers that have no biology expertise at all.
studies are a farce NOT science in any way, just BS those paying for the study desire it to find.
We have always been at war with Oceana’s plants.
And here I thought these CO2 “horror” stories couldn’t get even more silly. Boy was I wrong!
its funny watching wuwt wannabe lumberjacks take their chainsaws to science.
Widowmaker comes to mind