The AWEA Blog: Into the Wind


Study's lead author: News reports on wind and temperature 'misleading'

The lead author of a recent study finding that wind farms appear to affect local air temperatures has told a media watchdog group that he believes news stories on the study have been "misleading."

Liming Zhou, who led a team of researchers at the State University of New York-Albany (SUNY-Albany), made the comment in an e-mail to Media Matters, which published an analysis of media coverage of the study.  Referring to a Q&A originally published with a news release on the study, the group added: "The researchers, led by Liming Zhou, said it is "[v]ery likely" that "wind turbines do not create a net warming of the air and instead only re-distribute the air's heat near the surface, which is fundamentally different from the large-scale warming effect caused by increasing atmospheric concentrations of greenhouse gases."

Since the story broke on Sunday, a number of media outlets have joined the fray and have pointedly dismissed early, misleading reports in an effort to set the record straight. Some outstanding ones:

Washington Post WonkBlog: 'No, wind farms are not causing global warming': "Scientific studies are misrepresented all the time. But now and again the distortions get particularly bad. That was the case Monday, when Fox News ran the headline, “New Research Shows Wind Farms Cause Global Warming.” A number of other media outlets did the same thing. And it’s... not true at all."

Christian Science Monitor: 'Don't believe the headlines. Wind farms do not cause global warming.': "If it were true that the spinning blades of wind turbines increased the overall temperature of the planet, as opposed to simply redistributing thermal energy, we would have to rewrite some basic laws of physics, particularly the 2nd law of thermodynamics. This is an important distinction from the burning of fossil fuels, which produces gas that increases how much of the sun's energy the Earth retains. In this respect, this process contributes to a globally warming climate because the source of energy (the sun) is apart from the system that is warmed (the Earth.)"

 

NRDC's Switchboard Blog: 'Do Wind Farms Really Cause Climate Change?': "A number of news outlets have picked up a recent paper that looks at the local land surface temperature impacts of large wind farms. This has resulted in a number of headlines like 'Wind farms can cause climate change' and 'Wind farms linked to temperature increase' ... This wording is deeply misleading in this context and conflates small-scale, local impacts on nighttime land surface temperatures and global climate disruption. Using the same language to describe these two very different phenomena blatantly ignores the profound differences in magnitude, scope and severity that separate them. It’s like equating a bumblebee with Mothra."

 

Scholars and Rogues Blog: 'Wind farms affect local nighttime temperatures, not global warming': "The authors of the paper found that wind farms increase the nighttime surface temperature within and immediately downwind of the wind farm because the turbines mix up cold surface air with warmer air from up higher off the ground. What the authors did not find, however, was that wind farms were having any global effect on climate disruption."

Media Matters: 'Scientist Debunks "Misleading" Coverage of Wind Farm Study'

 

Knight Science Journalism Tracker: 'BBC: Wind farms change the wind. Nearby, a little bit. So study says. Not everybody sees it that way.': This brief survey article provides links and context for several stories on the topic.

 

(A similar "misinterpretation" of essentially the same information about wind farms and temperatures made the rounds just three months ago, as detailed by the U.K. newspaper Guardian's Environment blog: 'How the "windfarms increase climate change" myth was born', Feb. 7.)

American Wind Energy Association (AWEA) CEO Denise Bode yesterday released the following statement:

"This study says nothing about wind energy and global climate, and casts no doubt on all the other studies that find wind power is one of the best ways to address climate change. The study merely examined the effect of local air mixing at the site of a wind farm, which has nothing to do with climate because no heat or heat-trapping gases are being added to the atmosphere.

"All scientific studies including this one have found that any impact wind farms may have on local temperature readings is trivially small, and localized only to an area immediately around a wind project.

"We caution against people with an agenda who may try to misconstrue this study for their own purposes."

AWEA's Michael Goggin offered a more detailed "fact check" on this blog as well.  Key points:

Wind plants do not contribute to climate change, and in fact they are one of the leading technologies preventing climate change by avoiding fossil fuel use and the emission of greenhouse gases. Much of the popular reporting on this topic has confused the issue of climate change, which is a major global phenomenon driven by greenhouse gases actually warming the earth by altering the earth’s energy balance, and a speculative, small, short-lived, localized impact on the weather that could possibly be caused by wind plants slightlyaltering how air mixes around wind plants. It is important to emphasize that wind cannot contribute to climate change because any localized change in how air mixes is not a forcing of the climate or a change in the Earth’s energy balance. In contrast, greenhouse gases that are emitted into the atmosphere by producing and burning fossil fuels stay in the atmosphere and continue warming the planet every day in perpetuity.

In fact, the localized weather changes that the most recent study hypothesized were caused by wind farms may have actually been long-term warming caused by greenhouse gases or other changes in the climate. A comparison of NASA climate data from 2003 and 2011 – the time period covered by the most recent study that found a 0.72 degree Celsius localized change in weather in parts of Texas – shows that 2011 was a much warmer year than 2003 across much of North America. ...

All studies have found that any impact wind plants may have on local weather is trivially small. A primary conclusion of the study that has generated the recent press articles was that wind plants can cause a slight increase in nighttime temperatures and a slight decrease in daytime temperatures. All studies have found that any localized impact on the weather would be trivially small, less than a degree Celsius and localized only to an area immediately around a wind project. It is also important to point out that nearly all human activities can have an impact on localized weather phenomena, and the impacts of farming, building buildings, flying airplanes, and reforestation or deforestation are typically much larger than any localized impact found in this study.

Related articles:

Fact check: Flawed science journalism on wind energy, April 30, 2012


3 responses

  1. Andy Lee Robinson May 1, 2012 11:46PM
    When the air is warmer than the ground, and heat in the air at turbine-blade altitude is deflected towards the ground, the average ground temperature should increase, and the air temperature should correspondingly decrease as heat is transferred. Consequently, land temperatures further downwind where the air has restabilised should decrease by a smaller amount over a larger area, but nullifying the net heating. Some farmers ought to welcome this news. If they host wind turbines where ground temperatures hover around 0°C at night, then they won't need to use helicopters so often to help to clear frost from their crops. If this causes their neighbours land temperatures to drop slightly, then it might give a them little extra incentive to install some turbines too.
  2. Mike Barnard May 1, 2012 06:47PM
    Liming Zhou is complicit in this. His report's conclusions were not supported by his data; he wrote per decade trends based on 9 years data. His speculations about local and regional climate change were not supported by his research or balanced by any statements about significantly net positive benefits from moving away from fossil fuel generation. He's realized he's created a monster, but should not be left off the hook. His report was shoddily written and he deserves to suffer for it for a while. http://www.quora.com/Wind-Power/How-significant-is-the-recent-study-showing-ground-warming-at-night-under-wind-turbines/answer/Mike-Barnard
  3. Shawn Reeves May 1, 2012 02:35PM
    It doesn't matter that the effect is small...In fact it would be nice if the effect was larger, because the effect is to warm the land some but cool the air, more and the net local effect is cooling, since more energy is taken out of the air, by the combination of electricity through turbines and land exchange *and* increased into-space radiation from warmer land, than is put into the land. All AWEA should focus on in discussing this study is that by using satellite data the study is ignoring air temperature, as are all the cited media outlets. Instead, by using words like "trivial" and "small" they are implying that if wind farms were much more widely implemented, we'd have a problem. Shooting in the foot, that's called.

Please Enter Comments