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Will Wind Power Change Earth's Climate?
lommer writes "The Globe and Mail is currently running an article on a recent wind power study. A group of Canadian and American scientists has modelled the effects of introducing massive amounts of wind farms into North America and have come up with surprising results. While still having only 1/5th the impact of fossil fuels, wind power will still adjust the earth's climate with the equatorial regions warmed while the arctic grows colder. Could this be a boon for the nuclear lobby, or is this just further evidence for a diversified power-generating system?"
I'm not that much worried about power plant accidents. What worries me is that nobody has yet found anything to do with the wastes. Oh and there's no really sure way of stocking tons of wastes for centuries either.
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Like the study covered in the Globe and Mail, this is a simulated study of a specific type of turbine in a specific wind farm. Unlike the G&M study, this researcher was interested in microclimatological effects of windfarms.
Personally, I take these sorts of results with a whole shaker full of salt as the researchers need to make a whole raft of assumptions in order to get any result at all. (For instance,who says someone won't build a better windfarm?)
There is something wrong with this study.
/1000th of the total kinetic energy of the total heat exchange at most
The lower kilometer or so of the atmosphere is called the planetary boundary layer (PBL). It is not really modeled well in numerical atmospheric models, but is typically treated as a friction layer (i.e., given a single coefficient of friction). It is very hard to get these "lumped" coefficients of friction right - for example, they tend to be too low over mountain ranges.
The equator to pole temperature exchange occurs in the 20 km or so of the troposphere ABOVE the PBL. The PBL is barely involved, and is frequently ignored entirely in numerical models. Vertically averaged and spatially averaged, the pole to temperature heat exchange causes a wind of about 10 meters per second (in the 20 km of the troposphere above the PBL). To first order the PBL is decoupled to this and doesn't move at all (mean wind speeds of a few meters / second at most).
So how in the heck are even a forest of wind farms in the PBL (basically all of them except for any on mountain tops will be in the PBL) significantly slow down the heat exchange up in the troposphere when
- they hardly interact with it and
- the PBL has about 1
This doesn't pass the back of the envelope smell test; it's no wonder that they had such a hard time passing peer review.
Interesting troll. You're up to "5" and someone out there thinks there is insight in it so I'll bite.
[and I've got a degree in atmospheric physics and hate to see people believing crap...]
The jet streams are quite a bit higher than the wind mill which resides in the lower boundary layer. The wind mill is at 100m. The jet stream above 10 kilometers. By definition the jet has high shear, and a tiny bit of turbulence miles below is really just a grain of sand on the beach to it..
Sure there's an effect, it is just so small in a practical sense that it sums to near zero.
You got the bit about solar energy being transported to the poles correct. That doesn't make the rest of your argument float one bit though.
I wish you had taken the forest vs building thing further.. forests absorb *way* more energy than a few thousand windmills ever could. (look at mean wind conditions in Antarctica for example)
Of course if you do a study where you fill all of Canada with windmills spaced every 100m you start to increase drag.. so what- it isn't a realistic scenario.
You've got a theoretical and small problem from wind power. You've got a actual and large problem from fossil fuels. Therefore keep the status quo! Brilliant.