Deserts 'greening' from rising CO2

From CSIRO and “increased CO2 has benefits” department:

High_Resolution[1]

Satellite data shows the per cent amount that foliage cover has changed around the world from 1982 to 2010. Click for a full-sized and detailed image.

 Increased levels of carbon dioxide (CO2) have helped boost green foliage across the world’s arid regions over the past 30 years through a process called CO2 fertilisation, according to CSIRO research.

In findings based on satellite observations, CSIRO, in collaboration with the Australian National University (ANU), found that this CO2 fertilisation correlated with an 11 per cent increase in foliage cover from 1982-2010 across parts of the arid areas studied in Australia, North America, the Middle East and Africa, according to CSIRO research scientist, Dr Randall Donohue.

“In Australia, our native vegetation is superbly adapted to surviving in arid environments and it consequently uses water very efficiently,” Dr Donohue said. “Australian vegetation seems quite sensitive to CO2 fertilisation. 

The fertilisation effect occurs where elevated CO2 enables a leaf during photosynthesis, the process by which green plants convert sunlight into sugar, to extract more carbon from the air or lose less water to the air, or both.

This, along with the vast extents of arid landscapes, means Australia featured prominently in our results.”

“While a CO2 effect on foliage response has long been speculated, until now it has been difficult to demonstrate,” according to Dr Donohue.

“Our work was able to tease-out the CO2 fertilisation effect by using mathematical modelling together with satellite data adjusted to take out the observed effects of other influences such as precipitation, air temperature, the amount of light, and land-use changes.”

The fertilisation effect occurs where elevated CO2 enables a leaf during photosynthesis, the process by which green plants convert sunlight into sugar, to extract more carbon from the air or lose less water to the air, or both.

If elevated CO2 causes the water use of individual leaves to drop, plants in arid environments will respond by increasing their total numbers of leaves. These changes in leaf cover can be detected by satellite, particularly in deserts and savannas where the cover is less complete than in wet locations, according to Dr Donohue.

“On the face of it, elevated CO2 boosting the foliage in dry country is good news and could assist forestry and agriculture in such areas; however there will be secondary effects that are likely to influence water availability, the carbon cycle, fire regimes and biodiversity, for example,” Dr Donohue said.

“Ongoing research is required if we are to fully comprehend the potential extent and severity of such secondary effects.”

This study was published in the US Geophysical Research Letters journal and was funded by CSIRO’s Sustainable Agriculture Flagship, Water for a Healthy Country Flagship, the Australian Research Council and Land & Water Australia.

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pat

In fact all zones have had a measurable increase in biomass. Which will often be followed by an increase in atmospheric moisture. These are good things.

Kurt in Switzerland

That looks like rather good news! Are any of their results disputed?
I would be very interested to hear the comment from the Climate Science Establishment.
Kurt in Switzerland

Matt Bergin

We will but only after they quit gnashing their teeth sweep up the hair that is suddenly all over the floor.

Ashby

Interesting. I would think such an effect would also be somewhat cumulative e.g. those greened deserts may be capable of absorbing more CO2 over the near future as the plant density increases, thereby increasing natural carbon sinks.

BBould

Do we get the same CO2 readings from all over the globe?

Steve Case

Old news, but it needs to be repeated often.

Dodgy Geezer

Increased desert greening! A ruination of a natural environment!!
Won’t someone think of the lesser spotter sand lizards!!

Joe Crawford

Has anyone also tied in changes in precipitation to this increase in foliage? I would think that as the foliage increases the shadowing effect might reduce soil evaporation. I just don’t know whether the increased moisture lost by the foliage itself would be greater than that saved in the soil.

rabbit

Vegetation cools the atmosphere both directly through transpiration and through increased cloud cover. And as Ashby pointed out, vegetation is also a CO2 sink.
So the question is how much does this counteract CO2 greenhouse warming. A little? A lot?

sergeiMK

So an small increase in a trace gas can affect the vegitation – but the same increase can absolutely not have affect the climate!!.
Very strange, truly a magical gas.

Matt Bergin

SergiMK I think you will find that most of the people here agree that CO2 has some effect on the atmosphere it is the Catastrophic part we don’t agree with

sergeiMK,
Yes, that is true. You can see that at current concentrations, CO2 has no measurable effect on global temperature.
But it does have a measurable effect on plant life.

Brian Davis

SergeiMK, few would deny that CO2 affects the climate, just that it won’t lead to any dramatic or potentially catastrophic warming.

GregK

“We’ll all be rooned”
An increase in vegetation will lead to an increase in bushfires, which will lead to more CO2, which will lead to more vegetation, which will……….oh dear

Barry Cullen

@Pat – But if the atmospheric moisture is increased by the increase in vegetation, then you’ve found the link between CO2 and increased water vapor, THE main GHG, and we’re all doomed! It’s worse than I thought!
Sarc off/

Duster

Precipitation in desert areas is by definition scant to begin with. Locations within parts of the Atacama in Chile have never had measurable precipitation in recorded history. One point that is past over rather quickly is that photosynthesis fixes carbon dioxide by bonding it with water yielding carbohydrates. In desert regions, that water has to be available before the plants can use it. However, plant respiration often reverses at night resulting in nocturnal increases in CO2 and water vapor. Deep rooted pants will pull water from below the reach of others and then release during respiration. The darker foliage acts to precipitate dew (think Dune, the novel, not the film), so increased foliage can increase the surface availability of water. The spikey nature of many desert plants is ideal for precipitating dew and directing the droplets back to the plant’s trunk or main stem, or to the ground directly above the roots. The growth bounding limit is reached when the community demand for water balances available moisture, and the deeper rooted plants begin to compete for ground water, drawing down the elevation of ground water beyond reach of the deeper root systems..
This happens in forests as well as deserts and can be the direct result of fire suppression. A forester from the Deschutes N.F. in Oregon explained this, remarking that the beetles, while a problem, were really a symptom of the intense competition for water, which weakened trees. He concluded at the time that there were two or three times as many trees in the forest (in the 1990s) as the 19th century historical record indicated, and that fire suppression was the direct cause of the overpopulation that drew the beetle problems and directly caused the “drought” that was killing trees.

Chad B.

Looking at the very high intensity greening around the southern portion of the Sahara – does this mean that particular desert is shrinking? If so will the definition of desert (which I have normally heard in terms of inches of rainfall per year) need to change?

usurbrain

Rain is not needed to green an area. There are areas in the Hawaiian Islands that never receive rainfall yet they are covered with green grass and even support livestock. The grass receives much of its H20 from the dew that settles on it after the sun sets.

JEM

So get out there and remind your Prius-driving neighbor that they’re contributing to desertification.

JEM

A bumper-sticker for SUVs: “I’m doing more to feed Africa than Bono ever did”

DirkH

I guess they left out the Sahara and most of North Africa because a rise from zero to a positive number would be a bit inconvenient for their percentage scale?

DirkH

Look at the southern border of the Sahara – percentage increase at the top of the range, in other words – the drier and more arid a landscape was in 1982 the bigger the percentage increase. grey = infinity?

climatologist

Which came first, the temperature or the CO2?

Chad B.

Dirk,
The sections that are grey are still plantless. Check them out on google maps. Moving from 0% coverage to 0% coverage is technically an infinite gain. However, it is also an infinite loss as well. I think leaving it grey is appropriate.

Lady Life Grows

Carbon dioxide is the basis of all life (on Earth, anyway). CO2 and H20 are almost all that we are made of (with some, N,P, S and minerals thrown in here and there).
To get the CO2 from the air, plants have little openings on the undersides of their leaves, called stomata, the Greek word for mouths. The wider they are open, the more CO2 they get–and the more water vapor they lose. Thus, the increase in CO2 has had a water-sparing effect and our deserts are greening.
This is a good time to tell you all about a major crop science breakthrough called Sonic Bloom (R). A combination of specific sound frequencies and foliar feeding produces a large increase in plant growth, with a boost in nutrient values as well. It is organic, for those interested in that.
Research shows that this method of crop nutrition causes big changes to the stomata. They become larger and more detailed. The plants become much more drought tolerant, so much so that many farmers have had the biggest crop of their lives while drought killed their neighbors crops.
You can learn more and purchase your own test kit from http://www.originalsonicbloom.com This is a delightful website, full of colorful pictures and interesting stories. Disclosure: I do not get anything whatsoever from promoting Sonic Bloom(R) except the satisfaction of increasing life on Earth, which is my Life Purpose.

climatologist,
On more recent time scales, temperature came first. T even leads CO2 on a scale of hundreds of millennia.
CO2: the biosphere is starved of it. We need more CO2. More is better.

Brian Johnson UK

sergei
“So an small increase in a trace gas can affect the vegitation – but the same increase can absolutely not have affect the climate!!.
Very strange, truly a magical gas.”
Your sarcasm missed the fact that we humans only produce 3% of the Greening CO2, Mother Nature provides the rest……

Gras Albert

Hmmmmm
Trenberth and his mates are busy wringing their hands, casting about, fishing for any explanation for the missing heat! But heat is energy, energy that photosynthesis uses when producing record crop yields and a greening planet! Think of the work done an acre to lift the water, stems, trunks and leaves of crops, woodland and forest from below the surface to the height of maize, soft fruits and jungle canopy. And then multiply that by millions of acres…
A quick search provided not one reference to a paper estimating the extra work done and therefore energy required to explain such an obvious, massive increase in global vegetation…
Trenberth’s energy budget diagram doesn’t mention ‘green’ energy consumption, could it just be that the missing ‘heat’ can be explained by the increase in vegetation, for how else do plants grow?

Jimbo

Below is the above study I believe and some other recent paper abstracts on co2 fertilization.

Randall J. Donohue et. al. – 31 May, 2013
Abstract
CO2 fertilisation has increased maximum foliage cover across the globe’s warm, arid environments
[1] Satellite observations reveal a greening of the globe over recent decades. The role in this greening of the ‘CO2 fertilization’ effect – the enhancement of photosynthesis due to rising CO2 levels – is yet to be established……
http://onlinelibrary.wiley.com/doi/10.1002/grl.50563/abstract

May 2013
Abstract
A Global Assessment of Long-Term Greening and Browning Trends in Pasture Lands Using the GIMMS LAI3g Dataset
Our results suggest that degradation of pasture lands is not a globally widespread phenomenon and, consistent with much of the terrestrial biosphere, there have been widespread increases in pasture productivity over the last 30 years.
http://www.mdpi.com/2072-4292/5/5/2492

10 APR 2013
Abstract
Analysis of trends in fused AVHRR and MODIS NDVI data for 1982–2006: Indication for a CO2 fertilization effect in global vegetation
…..The effect of climate variations and CO2 fertilization on the land CO2 sink, as manifested in the RVI, is explored with the Carnegie Ames Stanford Assimilation (CASA) model. Climate (temperature and precipitation) and CO2 fertilization each explain approximately 40% of the observed global trend in NDVI for 1982–2006……
http://onlinelibrary.wiley.com/doi/10.1002/gbc.20027/abstract

MarkW

sergeiMK says:
July 8, 2013 at 10:00 am
—-
Who said CO2 has no impact on the climate? Nobody here.
The point is that CO2 has very little impact on the climate.
BTW, if CO2 weren’t a greenhouse gas, then yes, it could affect plants without affecting the climate.
Please learn to think before you post.

Jim from Maine

““Ongoing research is required if we are to fully comprehend the potential extent and severity of such secondary effects THAT OUR MODELS HAVE INDICATED EXIST.”
There…fixed it for ya.

Willis Eschenbach

Global farm production is worth on the order of 3 trillion dollars annually. Assuming that it’s not just the arid lands but all lands that have benefitted from the increased CO2, that’s a net social benefit from CO2 of $300 billion dollars per year.
Now, global carbon emissions are on the order of 10 billion tonnes per year these days. This means that the social benefit of carbon emissions is about $30 per tonne …
Somehow, when Obama declared his “social cost of carbon” figures, I doubt if he included that benefit …
w.

Bruce Cobb

“…however there will be secondary effects that are likely to influence water availability, the carbon cycle, fire regimes and biodiversity, for example,” Dr Donohue said.
Darn those pesky “secondary effects”. I guess they just had to throw those in, though. They just can’t help themselves. Tough for them to kick the “CO2 is eeevil” mantra.

Jimbo

It’s worse than we thought, we must act now.

Abstract (2013)
“…..,.,.the increase in gross primary productivity (GPP) in response to a doubling of CO2 from preindustrial values is very likely (90% confidence) to exceed 20%, with a most likely value of 40–60%…..”
Biogeosciences, 10, 339-355, 2013
http://www.biogeosciences.net/10/339/2013/
doi:10.5194/bg-10-339-2013, 2013.

Oh…and
PLEASE PLEASE PLEASE GIVE US MORE MONEY!
There…that oughta do it.
Jim

DirkH

Chad B. says:
July 8, 2013 at 10:58 am
“Dirk,
The sections that are grey are still plantless. Check them out on google maps. ”
Google maps updates photos of small German cities at most every 5 years. Why should they EVER update photos of the Sahara? I got a better idea, you go to google images and enter something like “green Sahara”. You will find photos of plants somewhere in the Sahara. Granted, these are isolated spots where wells are or rare rainfalls happened. But be that as it may – these plants should profit the most from rising CO2 as they are water-limited and can form less stomata when CO2 is higher. And – I would expect the border from the Sahel to the Sahara to shift. I would expect plants to conquer previously desert territory.

David Schofield

What happened to Sergei? Is a hit and run all they have?

Auto

So my failures in the gardening department are despite a surplus of plant steroids.
I’d better go back to making comments on WUWT than!
Auto

Ragnaar

Dusters says: “…remarking that the beetles, while a problem, were really a symptom of the intense competition for water, which weakened trees… …that fire suppression was the direct cause of the overpopulation that drew the beetle problems and directly caused the “drought” that was killing trees.” I had the privilege to take a nature walk in the Lubrecht Experimental Forest with a Professor from the U of MT, Missoula who was knowledgable in this area. We saw Beetles and magnificiant Ponderosa Pines. He mentioned that some thought is being given to letting Fire solve the Beetle problem under the right conditions. For example, a brush fire that doesn’t jump to the forest crown. Ocassional small fires keeps the brush load small enough so that fires cannot make the jump to the Ponderosa forest crown. The Ponderosa Pine has evolved to survive small fires just fine. Some do think that high levels of fire suppression have had a negative effect on Ponderosa Pines, increasing the chances of more severe forest crown level fires.

Old'un

Looks suspiciously like unacceptable NEGATIVE FEEDBACK to me. Excommunication is clearly looming for Dr Donohue and his fellow apostates.

Jimbo

Does anyone have an idea what the effect on water vapour would be?
It looks like water vapour has been flat / declining?, contrary to what the climate models assume.
http://pielkeclimatesci.wordpress.com/2012/07/16/new-paper-weather-and-climate-analyses-using-improved-global-water-vapor-observations-by-vonder-haar-et-al-2012/

Chas

Old’N “Looks suspiciously like unacceptable NEGATIVE FEEDBACK to me.”
-No need to worry because vegetation is mostly darker than soil so (other things being equal, which of course they aren’t) someone could claim that the lower albedo vegetation could lead to more warming ie positive feedback, which coupled to all the other positive feedbacks that get published means that earth should explode in a ball of flames , yesterday 😉

Kasuha

That map must be interpreted carefully. For instance, areas south from Sahara are in general “almost desert” with very little vegetation so even large relative increase (30%) does not mean very large total increase in biomass.
I would really like to see also a map describing absolute biomass amount changes.

John

To Kurt in Switzerland (9.28 comment):
Yes, of course this is bad news! How ignorant can you get???
Anything that is adapted to the precise level of aridity, and the precise plant community of two decades ago, may be facing extinction! You thoughtless Swiss, Nature can’t possibly be so resilient as to tolerate vegetation growing a bit better and saving a little more water!!
I thought you might be sensitive to our planet, but now I see that you are an ignoramus whose lack of understanding will mean that you will be implicitly implicated when climate disaster strikes the earth! Oooooh, I can’t stand this pain any longer, living on the same planet with people like you!!

RockyRoad

How diabolical that the country fighting CO2 the most is having the most benefit.

Louis

Gaia worshipers are going to be doubly upset at CO2 when they find out it might be helping to fulfill a Bible prophesy: “…and the desert shall rejoice, and blossom as the rose.” – Isaiah 35:1

DirkH

RockyRoad says:
July 8, 2013 at 12:39 pm
“How diabolical that the country fighting CO2 the most is having the most benefit.”
Are you Australian? Well in that case, we appreciate that you fell for Kyoto, but as a German I’d like to insist that we’re getting ripped off even more (by our own government whose only talent is to out-green the Greens).

RockyRoad

Kashua, I’ve read that parts of the Sahel (strip immediately south of the Sahara) were nothing but sand with nary a blade of grass half a century ago are now verdant grazeland. That’s not a very quantified difference, admittedly.

Chas

And what is worse.. the green vegetation might lead to more water being excavated causing more clouds and more precipitation and oh no …. more green vegetation… aaaaah.
Of course this extra vegetation is bad because it is anthropogenic.
Just as less vegetation is bad (desertification) because that is caused by humans.

Chas

…In fact the Christian religion’s arcadian vision of a garden of eden has a lot to answer for.
Yes, we are piloting spaceship earth but we now have too many nagging back seat drivers.
We should stop the car and tell these mother in law types to get out.