New Study Suggests Wind Farms Can Cause Climate Change 384
nachiketas writes "A study led by Liming Zhou, Research Associate Professor at the Department of Atmospheric and Environmental Sciences at the University of New York concludes that large wind farms could noticeably impact local weather patterns. According to Professor Zhou: 'While converting wind's kinetic energy into electricity, wind turbines modify surface-atmosphere exchanges and transfer of energy, momentum, mass and moisture within the atmosphere. These changes, if spatially large enough, might have noticeable impacts on local to regional weather and climate.'"
Re:Local impact = climate change? (Score:4, Informative)
"These changes, if spatially large enough, might have noticeable impacts on local to regional weather and climate."
Headline matches the summary.
RTFA before writing headline (Score:3, Informative)
From TFA:
However Prof Zhou pointed out the most extreme changes were just at night and the overall changes may be smaller.
Also, it is much smaller than the estimated change caused by other factors such as man made global warming.
“Overall, the warming effect reported in this study is local and is small compared to the strong background year-to-year land surface temperature changes,” he added.
...
“This makes sense, since at night the ground becomes much cooler than the air just a few hundred meters above the surface, and the wind farms generate gentle turbulence near the ground that causes these to mix together, thus the ground doesn't get quite as cool. This same strategy is commonly used by fruit growers (who fly helicopters over the orchards rather than windmills) to combat early morning frosts.”
Re:Local impact = climate change? (Score:5, Informative)
This has nothing to do with climate change, which is a change to the underlying system.
By that logic, there is no such thing as climate change. CO2 emissions do not change the underlying system, and were they do stop completely, the system would, in time, revert/adjust. By your logic, climate change can't exist unless thermodynamic laws (or whatever) are changed.
Anyone who thinks that the deployment of [technologies] across large portions of Earth's surface will not have significant impact is delusional. Don't be that guy.
All "clean" energy, whether wind, solar, hydro, coal, fission, etc. is merely "relatively" clean. Wind kills birds and warms areas downstream. Coal makes smog and dumps carbon. Hydro kills fish and and alters local climate. Fission makes giant lizards emerge from Tokyo bay...
Re:Local impact = climate change? (Score:5, Informative)
Cats, power lines and shiny glass buildings kill more birds than wind farms. Of course we don't have that many wind turbines yet, but still the figures don't look that scary. http://science.howstuffworks.com/environmental/green-science/wind-turbine-kill-birds.htm [howstuffworks.com]
Wind farms apparently do weird shit to bats though: http://www.newscientist.com/article/dn14593-wind-turbines-make-bat-lungs-explode.html [newscientist.com]
It only causes measurement problems (Score:4, Informative)
Windfarms only cause apparent climate change when meteorologists have their thermometers on the ground. Mixing air of different temperatures doesn't heat it, not while the conservation of energy is valid.
Re:I've never understood... (Score:5, Informative)
You're forgetting how few people actually understand thermodynamics.
I imagine most people (and politicians) think wind / solar / tidal energy = magically free energy, with an emphasis on the word magic.
Re:Robert Heinlein (Score:2, Informative)
> Would these locations prefer a windmill farm or coal fired plant.
Oh, wow. This is the most blatant example of a false dichotomy I have seen for days. There are many other options, all of them more practical. Note, especially, the human death rate per Terrawatt-hour of energy produced here: http://www-958.ibm.com/software/data/cognos/manyeyes/visualizations/deaths-per-twh-by-energy-sources [ibm.com] and look at the bottom of the graph on the right (consistent with http://nextbigfuture.com/2011/03/deaths-per-twh-by-energy-source.html [nextbigfuture.com] which has discussion attached to the numbers). This is a rate lower than even that of wind, but there's a more important reason that this method is much better than wind: it's the only alternative to coal that can meet all of the world's energy needs as developing world per-capita usage energy use explodes to match that of the developed nations. You can't cover every square mile of the planet with wind towers.
Re:I've never understood... (Score:5, Informative)
Wind farms *MIGHT* perceptably slow down air near the surface of the earth only... within a hundred meters or so.... in a not entirely dissimilar way to how buildings can shelter people from wind.
But you could cover the entire planet with wind farms, and that would have negligible impact on the earth's climate because 100 meters is positively puny compared to the total size of the earth's atmosphere. It would impact even less than buildings because buildings actually block the air, where turbines let it all through. Further, the cross sectional area of a blade that is 10 meters long is perhaps at most about 10 square meters, while the total swept area of a blade that long is over 300 square meters. Allowing for the fact that there are 3 blades per turbine, the turbine is only affecting (at most) 10% of the air that is passing through any given turbine. And again, it's not actually stopping it... it's passing right through. Coupled with the absolutely enormous mass of air above the turbines that is even more negligibly affected by the presence of stuff on the ground, the net impact on climate stands to be somewhere near nil.
One might as well suggest that harnessing the energy from tides might perceptibly impact the orbit of the moon...
Re:Local impact = climate change? (Score:5, Informative)
Coal doesn't make whole areas uninhabitable
Yes it does. Ever seen a strip mine?
Re:Local impact = climate change? (Score:2, Informative)
No, it's the conditional. The future tense (in this case) is "will", the future conditional is "would".
I can walk.
I will walk, tomorrow.
I could walk, if I had legs.
I would walk tomorrow, if I had legs.
Could implies that there will be an if coming up soon.
Re:Local impact = climate change? (Score:4, Informative)
These changes, if spatially large enough, might have noticeable impacts on local to regional weather and climate.
I think the implication is that a world covered in wind farms would experience climate change, which is improbably indeed
Umm, no. From a few sentences around the quote you cherry picked FTFA:
However Prof Zhou pointed out the most extreme changes were just at night and the overall changes may be smaller.
Also, it is much smaller than the estimated change caused by other factors such as man made global warming.
“Overall, the warming effect reported in this study is local and is small compared to the strong background year-to-year land surface temperature changes,” he added.
The study read: "Despite debates regarding the possible impacts of wind farms on regional to global scale weather and climate, modelling studies agree that they can significantly affect local scale meteorology."
The effect is localized, remains localized, and does not have anywhere near the same impact as "other factors such as man made global warming". The use of the word "extreme" to categorize a 1.37F change in overnight temperatures in a ten year period is a bit, well, extreme. It's good that they did notice this effect and my guess is something will be done to the turbine design to mitigate this 0.72C (1.37F) over ten years change in localized, overnight temperatures near wind turbines. This is much ado about nothing but I am sure the climate change extremists will be all over it, while the rest of us who do believe and are trying to do something rational about climate change will put this on a low priority. The benefits of renewable energy still outweigh that ridiculously low cost with current turbine designs. If things stay static this might be a problem. Given that the research is out, I am sure there will be a reaction. The important thing is not to come unhinged and react a bit too wildly to every bit of negative data that comes up. This is really not that big a problem it can't be designed or engineered around, and I believe even Prof. Zhou would agree.
Windmills will reduce global warming and CO2 (Score:3, Informative)
The reason fossil fuels are well known to cause climate change is the effect is, practically permenant since we are raising the level of the CO2. The CO2 will STILL BE THERE after we stop burning fossil fuels, even after we have depleted every bit of coal and oil, it will be in the atmosphere for a long time. The idea that wind farms would cause warming is absurd, since wind farms could displace Co2 consumption they would reduce it by reducing Co2 emissions. The effect of reducing or eliminating CO2 would have a far greater positive impact than any negative of wind. The effet of Co2 is permenant and irreversible. A Wind farm can be turned on and off at will.
Another reason for these renewables is they are renewable, climate change is happening but the fact tht solar and wind are renewable alone makes them better choices than fossil fuels. Fossil fuels will be depleted, first hitting peak and then decling, hence peak oil. THAT is an absolute, gauranteed physical certainty. It is hard to precisely estimate how much longer fossil fuels will last but they WILL run out. And sooner than later. Since data on how much is in the ground is imprecise there is uncertaintly in the precise amount but we have a general idea. Its like you have an hourglass and you can see that the top half of the hourglass is a certain size, but you dont know how far it is filled with sand, because the top half is opaque, but you can see how much has poured into the bottom half and how long it has been pouring in there, thus a rate of depletion,, you know that there is a finite amount of sand in the top half and that it is emptying out, and you can see by the rate it is emptying that the sand will be depleted not too far from now, even though you do not know exactly when, you know it will happen and it is not that far away. The "cornucopians" who think thje earth has an unlimited amount of fossil fuels and that basically we can do anything, that the laws of nature dont matter, that we can if we want generate infinite amounts of fossil fuel energy, basic physics be damned, well, they are basically saying that since we cannot see the amount of sand in the top half of the hourglass that since we cannot make a precise measurement that therefore we might as well just assume the amount of sand is infinite. This is despite thje fact that the top half of the hourglass is of a finite size, the sand is pouring out quickly and already a lot has poured out.
Basically the cornucopias, they are living in a fantasy world, insisting the top half of the hourglass contains an infinite amount of sand, are in denial about the dire state of affairs and the fact we are headed towards practical depletion of fossil fuels.
Re:Local impact = climate change? (Score:4, Informative)