Large wind and solar farms in the Sahara would increase heat, rain, vegetation

September 6, 2018, University of Illinois at Urbana-Champaign
Large-scale wind and solar installations in the Sahara would increase precipitation, a new study finds. Credit: Map by Eviatar Bach CC BY 4.0

Wind and solar farms are known to have local effects on heat, humidity and other factors that may be beneficial—or detrimental—to the regions in which they are situated. A new climate-modeling study finds that a massive wind and solar installation in the Sahara Desert and neighboring Sahel would increase local temperature, precipitation and vegetation. Overall, the researchers report, the effects would likely benefit the region.

The study, reported in the journal Science, is among the first to model the climate effects of wind and solar installations while taking into account how vegetation responds to changes in heat and precipitation, said lead author Yan Li, a postdoctoral researcher in natural resources and environmental sciences at the University of Illinois.

"Previous modeling studies have shown that large-scale wind and solar farms can produce significant climate change at continental scales," Li said. "But the lack of vegetation feedbacks could make the modeled climate impacts very different from their actual behavior.

The new study, co-led with Eugenia Kalnay and Safa Motesharrei at the University of Maryland, focused on the Sahara for several reasons, Li said.

"We chose it because it is the largest desert in the world; it is sparsely inhabited; it is highly sensitive to land changes; and it is in Africa and close to Europe and the Middle East, all of which have large and growing energy demands," he said.

The wind and simulated in the study would cover more than 9 million square kilometers and generate, on average, about 3 terawatts and 79 terawatts of electrical power, respectively.

"In 2017, the was only 18 terawatts, so this is obviously much more energy than is currently needed worldwide," Li said.

The model revealed that caused regional warming of near-surface air temperature, with greater changes in minimum temperatures than maximum temperatures.

"The greater nighttime warming takes place because can enhance the vertical mixing and bring down warmer air from above," the authors wrote. Precipitation also increased as much as 0.25 millimeters per day on average in regions with wind farm installations.

"This was a doubling of precipitation over that seen in the control experiments," Li said. In the Sahel, average rainfall increased 1.12 millimeters per day where wind farms were present.

"This increase in precipitation, in turn, leads to an increase in vegetation cover, creating a positive feedback loop," Li said.

Solar farms had a similar positive effect on temperature and , the team found. Unlike the wind farms, the solar arrays had very little effect on wind speed.

"We found that the large-scale installation of solar and wind farms can bring more rainfall and promote vegetation growth in these regions," Kalnay said. "The rainfall increase is a consequence of complex land-atmosphere interactions that occur because solar panels and wind turbines create rougher and darker land surfaces.

"The increase in rainfall and vegetation, combined with clean electricity as a result of solar and wind energy, could help agriculture, economic development and social well-being in the Sahara, Sahel, Middle East and other nearby regions," Motesharrei said.

Explore further: The public health benefits of adding offshore wind to the grid

More information: Y. Li el al., "Climate model shows large-scale wind and solar farms in the Sahara increase rain and vegetation," Science (2018). science.sciencemag.org/cgi/doi … 1126/science.aar5629

Related Stories

Wind energy's swift growth, explained (Update)

April 23, 2018

The wind industry is growing quickly around the world, especially in China and the U.S., where the total amount of electricity generated by wind turbines nearly doubled between 2011 and 2017.

Recommended for you

44 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

MR166
1.4 / 5 (13) Sep 06, 2018
The first sand storm and the whole project would be toast.
Grallen
3.7 / 5 (7) Sep 06, 2018
You really think that?...
howhot3
4.3 / 5 (9) Sep 06, 2018
Such Doom and Gloom. An earthquake could have big consequences around a nuclear plant or hydroelectric plant for that matter. Then everybody's toast. Damn the risk Full Speed Ahead with the Sahara solar/wind.
Thorium Boy
1.4 / 5 (11) Sep 07, 2018
This is wholly-unsupported global warming nonsense. One the one hand, the gwk's pretend the heat island effect doesn't impact climate, which when you have a city of 5 million and an area of 300 square miles, THAT has an impact. A few hundred acres of solar panels and windmills have NO effect on a desert of 50 MILLION square miles.
fireofenergy1
4 / 5 (4) Sep 07, 2018
We still need an entire watering infrastructure, including lots of desalination plants, in order to reverse global warming.
Vast infrastructure will be needed to water the C4 plants necessary, that sequester the excess CO2 deep into the soil, and which gives rise to an entire new continent's worth of agriculture, which has to be done without pesticides. This transition to multispecies agriculture has to occur with existing croplands, too, in order to get the full benefit of excess CO2 sequestration and healthy organic food, worldwide.
9 million sq km is about the entirety of the Sahara desert, and surely, we don't have to cover it all with dark (very hot) solar panels. 20 TW on average solar and 1/2 left for Ag and cities. Save other 1/4 of the desert to be left natural.
Connect to other desert solar via global grid.
That's the cheapest, most profitable, pro growth way to become a type 1 civilization AND reverse global warming at the same time!
Partisan unity, too!
Joker23
1.6 / 5 (13) Sep 07, 2018
Global Warming, Global Warming...it's bad..we need a carbon tax......oh Global warming, Global warming,,Solar energy, wind farms.......oooohhhh, that could increase Precipitation, cause warming and benefit the area....................Just exactly what am I missing here? When will these envioro-idiots take a course in Thermodynamics and find that:: Ta Daaa...There is no such thing as ''free energy''.
greenonions1
4.5 / 5 (8) Sep 07, 2018
Joker
.There is no such thing as ''free energy''
What does that have to do with this topic? If I put my solar cooker in the sun, and boil some water - is that not free energy? Please elaborate on your point here.
antialias_physorg
4.1 / 5 (13) Sep 07, 2018
The first sand storm and the whole project would be toast.

You really need to start getting your world view from other sources than Hollywood movies.
RyanHeins
5 / 5 (5) Sep 07, 2018
I remember some research showing a huge amount of dust and sand from the Sahara gets lifted high in the atmosphere, carried across the Atlantic, and deposited in the Amazon rain forest acting as fertilizer. What happens to that process if we increase vegetation in the Sahara? Moreover, how can we pretend to understand what will happen when we try to change the climate of a region as large as the Sahara?
greenonions1
4 / 5 (4) Sep 07, 2018
Ryan
Moreover, how can we pretend to understand what will happen when we try to change the climate of a region as large as the Sahara.
I don't think we can Ryan. Kind of a catch 22 right. If we can't fully understand the consequences of our actions - does that mean we should do nothing, and then not fully understand the consequences of doing nothing - which is of course not doing nothing - as we are pumping millions of tons of C02, and other pollutants into the atmosphere. So maybe the best course of action is to predict the best we can, make the best choices we can based on current data, and then monitor, and adjust as we go.
Surveillance_Egg_Unit
2.1 / 5 (7) Sep 07, 2018
All breathing life forms are pumping out CO2 every time they exhale. Does the CO2 factor mean that we should stop breathing because we are producers of a GHG?

And plants and trees require CO2 to grow. That is their food. Would you deprive plants and trees of their food? Plants also exhale Oxygen at night and would not be able to exhale Oxygen if they did not take in CO2 in the first place.

Cause and effect is not always a bad thing. What IS bad is the wanton pollution and pollutants that humans carelessly and unconcernedly litter the planet with, with no thought but their own needs and desires.

And in the State of California, the homeless are allowed to defecate in the streets of San Francisco without much thought to how to prevent it from happening. The only concern is how to continue to allow such humans to do whatever they please without also displeasing visitors and tourists. Democrat politicians are a stain on society and the proof is right there in that city.
Surveillance_Egg_Unit
2.3 / 5 (6) Sep 08, 2018
I remember some research showing a huge amount of dust and sand from the Sahara gets lifted high in the atmosphere, carried across the Atlantic, and deposited in the Amazon rain forest acting as fertilizer. What happens to that process if we increase vegetation in the Sahara? Moreover, how can we pretend to understand what will happen when we try to change the climate of a region as large as the Sahara?
says RyanH

It also covers European cities:

https://www.cityl.../477081/

https://www.washi...4ef2b191

http://www.eurone...o-europe
greenonions1
5 / 5 (6) Sep 08, 2018
Surveillance
Democrat politicians are a stain on society
So - when commenting on an article about the effect of installing large scale wind and solar in the Sahara Desert - you veer off into homeless people defecating in the Street - and attacking Democrat (now making it U.S. centric) politicians. I would agree with you that we have some serious problems in our society - such as poverty, homelessness, crime, disease etc. etc. I would not agree with your characterization of the nature of the cause (Democrat politicians.) I think it is way more complex than that - but that one of the issues - is really stupid people - who engage in tribal politics vs complex, solution base thinking.
Surveillance_Egg_Unit
2.1 / 5 (7) Sep 08, 2018
LOL it certainly isn't the Republicans in San Francisco who are allowing all the streets to be littered as such by, not only homeless people, but by the mentally ill whose rights to defecate in the streets are protected by Democrat Party politicians...those who regard themselves as the protectors of the voluntarily indigent who voluntarily pollute the streets of that formerly beautiful city. Such pollution in the streets, sidewalks, alleyways, and parks is a symptom of what the Democrat politicians have allowed to happen and to continue happening as long as they have been in power.
And children, with or without their parents cannot walk the streets without seeing used hypodermic needles thrown casually on the sidewalks and other places.
The Democrat-led city of San Francisco is a dangerous place now, and it has been deemed by many visitors, as well as residents.
There are many kinds of pollution and pollutants, and the Dems aren't too concerned about this one. Talk is cheap
Surveillance_Egg_Unit
2.3 / 5 (6) Sep 08, 2018
The Sahara was once a sea called Tethys - this indicates that it is/was a natural and normal process that occurred long before humans had the ability to change the climate as some believe.

https://www.smith...0952735/

The Earth is a living dynamo and nobody can stop her when she insists on changing things her way. But humans should be educated as to the prevention of further pollution of the planet - including that of Nuclear processes.

Windmills in the Sahara could be either detrimental - or beneficial. But it seems to me that the flight of sand to other parts of the world, caused by wind as it is - may cause unforeseen problems if windmills are installed in the desert.
Surveillance_Egg_Unit
2.3 / 5 (6) Sep 08, 2018
I was quite impressed with this part, because it may be the cause of the surge of humans "out of Africa" when the Sahara became a desert.

"The emergence of the Sahara 7 million years ago would have affected the plants and animals in the region—and possibly the early ancestors of human beings. For instance, Sahelanthropus tchadensis, which may be the earliest member in the human family tree, lived just to the south of the Sahara (in what is now northern Chad) around the time of the transition. Overall, the team writes, the study adds to evidence that changes in precipitation "were fundamental to the evolution and dispersal of hominins in north Africa." "
Old_C_Code
2 / 5 (8) Sep 08, 2018
greenFrontalLobes says: "... as we are pumping millions of tons of C02, and other pollutants into the atmosphere"

CO2 is not a pollutant. You brainwashed dope.

The man made 30% rise in CO2 has made Earth greener. FACT.
greenonions1
4.3 / 5 (6) Sep 08, 2018
CO2 is not a pollutant. You brainwashed dope

Although it has some very important and beneficial effects, CO2 meets the legal and encyclopedic definitions of a "pollutant", and human CO2 emissions pose a threat to public health and welfare
You're good with the expletives Old_C - but not so good when it comes knowledge. Maybe I am brainwashed. I certainly was as a child - growing up in a conservative christian home - and being fed a diet of bullshit from the bibull. Broke myself out of that one - and consider myself more of a free thinker now.
The man made 30% rise in CO2 has made Earth greener. FACT
We know that - we can read - you brain washed dope. https://phys.org/...rth.html
We also know of the downside to suddenly loading our atmosphere with carbon - https://www.futur...34522-2/
If you read more - you might understand more - you brain washed dope...
Old_C_Code
2.1 / 5 (7) Sep 08, 2018
greenCerebralHemorrhage: futurity.org? LOL, you are brainwashed man.
Old_C_Code
2 / 5 (8) Sep 09, 2018
greenBrainStem says: "We also know of the downside to suddenly loading our atmosphere with carbon"

No we don't. That's complete BS.

You have no idea. And you guys deserve insults from the endless lying doom & gloom this GW crowd spews.
greenonions1
4.3 / 5 (6) Sep 09, 2018
No we don't. That's complete BS
Yes we do - because we have thousands of scientists studying it. For example - the scientists studying the ocean - are sounding big alarms on many fronts. Micro plastics from the millions of tons of plastics getting dumped - are getting into the food chain, and showing up in our bodies. Aciidification is threatening coral reefs, and negatively impacting many life forms - https://www.pmel....ation%3F Over fishing is causing fish populations to plumet - https://www.thegu...r-oceans
you guys deserve insults
For being concerned about the future of our planet. No - science deserves a more educated world - in which we pay attention to the data. Sadly there are too many people like you - who are ignorant/arogant, hate science, and so full or your own importance - you are proud of throwing insults.
HannaB
2.3 / 5 (3) Sep 09, 2018
The first sand storm and the whole project would be toast
Not just sand storms. The subSaharian Africa is full of aggressive Muslim and nomadic tribes, which don't respect any borders, private property the less. But I doubt this project would ever pay its way.
Old_C_Code
1.6 / 5 (7) Sep 09, 2018
Thousands of scientists yes, getting funding from government grants, for a religion.

We are fed up with your bulls*** greenBrain

greenonions1
5 / 5 (4) Sep 09, 2018
Thousands of scientists yes, getting funding from government grants, for a religion
Science is not a religion. It is simply the exploration of what is. You should do some reading on the subject. Much medical research is funded by the N.I.H. Do you think doctors are part of a religion - and trying to do nefarious things with our bodies - in order to support their religion?

We are fed up with your bulls*** greenBrain
Who is 'we?' What group do speak for? I speak for myself alone.

Look at your first comment. The need to blurt rubbish out on a science site - in order to promote conspiracy theories. Who is full of shit?
Old_C_Code
2 / 5 (8) Sep 09, 2018
I didn't say science is a religion. Your doom & gloom climate science is though.

A bunch of young punks and old goofs with no courage to even begin to question this insane so called 'science'.

The Sun is easily the biggest factor in long term climate, and it's never mentioned!
Old_C_Code
2 / 5 (4) Sep 09, 2018
My first comment = >The man made 30% rise in CO2 has made Earth greener. FACT.

Rubish? You truly are brainwashed, as a child by your parents, as an adult by your cowardice.

Conspiracy theory? God you are as dumb as pntaylor.
gkam
3 / 5 (2) Sep 09, 2018
C code does not seem to realize when he call names, it is obvious that he lost the argument.

Ignorance , . pure ignorance, spurred on by hate and political prejudice.

Life is much more complex than eight digits.
Old_C_Code
2.3 / 5 (3) Sep 09, 2018
gkam: you are dopes, you need to know you are full of s***.

No argument lost you idiot, you won't answer the question because you are brainwashed fools.

I asked what does a man made 30% increase in CO2 do to Earth?

The correct answer is: we don't know, but it has made Earth 14% greener.

You deserve the name calling you meathead.
greenonions1
3 / 5 (2) Sep 09, 2018
You deserve the name calling you meathead
As do you - you show total ignorance of the subject.

Apologies about mixing up the comments - I was mixing up your first comment on the other thread - claiming there was a farm in the picture - and thus the glacier could not be retreating. The point being that you are like a little child - always waiting to jump in and show how you know better than the scientists - but you clearly really know nothing. We do know a lot about what adding carbon to the atmosphere is doing - and the science says it is not a good thing to do. Fortunately you are in a minority - bunch of deniers who don't understand science - and the ship is turning. We are trying to heed the science - and develop the technologies to free ourselves from FF. You will for sure go down in history as one of the idiots..
Old_C_Code
3 / 5 (2) Sep 09, 2018
greenBrainStem: you'll go down in history as unaccomplished, your writing proves it. Though it's nice to see you admit that you don't know s*** about what the climate will do.
But pretend you do, till someone starts calling you names....lol
Old_C_Code
3 / 5 (2) Sep 09, 2018
What has a man made increase of 30% CO2 done to Earth?

How is that question non-science? You dumbazz.
greenonions1
5 / 5 (2) Sep 09, 2018
you'll go down in history as unaccomplished
Probably. You don't know me - and what history will say of me is irrelevant to a discussion of science. You continue to show such a lack of understanding of basics. Your opinion, and my opinion mean nothing.
you don't know s*** about what the climate will do
Well - I know some stuff about what the climate scientists tell us. They said it would get warmer, and it did. Same for melting ice sheets. So to say that we 'dont know shit' (double negative by the way) - are you from the rural south by any chance? - about what the climate will do - makes you double ignorant. The models have been validated - and we are building on that knowledge.
till someone starts calling you names....lol
Your name calling just shows up your ignorance.
greenonions1
5 / 5 (1) Sep 09, 2018
Old_C
The Sun is easily the biggest factor in long term climate, and it's never mentioned

Corrrection - you don't think it is ever mentioned - because you don't read any science - and you don't know how to use google.
https://www.ucsus...tR-hKiM8
https://history.a...olar.htm
https://www.clima...y-source
https://eos.org/p...-climate
https://phys.org/...ied.html
https://e360.yale..._warming
https://www.scien...99000724
https://www.scien...5858.htm

I could go on all day. Enjoy the reading...
Old_C_Code
3 / 5 (2) Sep 09, 2018
I don't read any science? Ugh... Dude that's so lame...

That's only 8 links on the Sun, they are good, but there are 10's of thousands of climate article links. The IPCC doesn't think the Sun even matters!!!

http://ipcc.ch/

greenonions1
3.4 / 5 (5) Sep 09, 2018
That's only 8 links on the Sun
Cuz there's a limit of 1000 characters - i could have continued all day. Anyhow - your statement was "and it's never mentioned." Which is clearly false - and shows you don't know science. The sun, and the suns influence on the climate is heavily studied - with volumes of research on the subject.
Dude that's so lame...
Seems very consistent with the level of your comments. For example "and it's never mentioned."
Ojorf
2.5 / 5 (8) Sep 10, 2018
What has a man made increase of 30% CO2 done to Earth?

How is that question non-science? You dumbazz.


It's total obvious nonsense you brain dead unpaid troll. You have to be so far in denial to make such a stupid statement and believe yourself.

The science of CO2 is not complicated, it is well understood and experimentally verified many, many, many time over many years.
The climate records are also in agreement. Your bullshit about CO2 rise following temperature increases has been debunked and explained at least a decade ago. It was a favorite of the science illiterate goons back then. You really should catch up.
EnricM
not rated yet Sep 10, 2018
Interesting, but... what scale are we talking about?
A wind farm as broad as the Sahara ? Because I do not see how the scales we are managing right now would fo any difference. Sure at a very limited local scale, but this is irrelevant.
Old_C_Code
3 / 5 (4) Sep 10, 2018
The Sun heavily studied? AND IGNORED, you arrogant buffoon who pretends to defend science, what an awful defender.
Old_C_Code
3 / 5 (4) Sep 10, 2018
OjorfOutTheMouth says: "It's total obvious nonsense you brain dead unpaid troll."

Why would a paid-troll be stupid? LOL, You idiot.

All these expert "scientists" teaching us about CO2, what's been verified you dope?

Ojorf
2.3 / 5 (6) Sep 10, 2018
No use trying to explain it to you.
No use linking to scientific articles.
How can anyone be convinced if they don't believe in science?
Rational argument, concrete evidence and solid theory is meaningless to you.
What else is there Old_C? How can you be convinced of the truth?
vlaaing peerd
5 / 5 (3) Sep 10, 2018
Interesting, but... what scale are we talking about?
A wind farm as broad as the Sahara ? Because I do not see how the scales we are managing right now would fo any difference. Sure at a very limited local scale, but this is irrelevant.


It's in the article: "9 million square kilometers and generate, on average, about 3 terawatts and 79 terawatts of electrical power, respectively."

Which is almost the size of the entire Sahara.
greenonions1
5 / 5 (2) Sep 10, 2018
Old_C
The Sun heavily studied? AND IGNORED
It is not ignored. It has been studied - along with the question of how much influence it has on our climate. https://www.yalec...the-sun/ (that is just one example of a site - that you could find if you learned to use google.)
you arrogant buffoon who pretends to defend science
I try to defend science - you are probably right - I am probably not too good at it - but so what. Science does not need me - I understand my place in the scheme of things - unlike cock sure deniers like yourself - who know nothing - but think they know everything.
leetennant
5 / 5 (3) Sep 10, 2018
Joker
.There is no such thing as ''free energy''
What does that have to do with this topic? If I put my solar cooker in the sun, and boil some water - is that not free energy? Please elaborate on your point here.


But you're using up the SUN!

howhot3
5 / 5 (1) Sep 11, 2018
greenBrainStem says: "We also know of the downside to suddenly loading our atmosphere with carbon"

No we don't. That's complete BS.

You have no idea. And you guys deserve insults from the endless lying doom & gloom this GW crowd spews.

Actually, WE do know. If you look at any of the meteor strikes on Earth that caused Extinction events the end result is exactly what you would expect when you loft gigatons of CO2 into the air very rapidly. The global warming events from the additional CO2 from the carbon released by the meteor strikes are recorded in history. Unless course you don't believe in history. If you're skeptical just think of an asteroid striking and creating a super volcano type crater. These kind of events are very rare. But mankind has done it in less than a century from fossil fuel combustion.

That's the deal that we are all concerned about with global warming. Can we stop it.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.