[yamo (OP)]

If wind power is implemented on a large scale, what will happen to weather patterns when large amounts of energy are removed from the systems?

[Mr. F]

Yes, No, May be.

http://www.atmos.umd.edu/~dankd/Windfarms.html [nofollow]


Recent work (Keith et al., 2004) on the climate impact of very large scale wind farms has demonstrated appreciable effects on surface temperature, including warming and cooling on the order of a degree Celsius. Keith et al. (2004) simulated the impact of wind farms by increasing the roughness length (z0) in the boundary layer schemes of GFDL and NCAR CAM 2.0 general circulation models over large rectangular groups of grid points over North America, Europe and Asia. Models were run in fixed-SST mode. The increase in roughness led to circulation changes which in turn led to temperature changes. These temperature changes were not related in an obvious way to the imposed roughness length changes: for instance, temperature changes were not significantly larger over the simulated wind farms than over other regions. The figure below shows the temperature change at 2 m above the surface due to the increased roughness. The regions of increased surface roughness are outlined in black. Significance is indicated by stippling.

Read more: http://www.atmos.umd.edu/~dankd/Windfarms.html [nofollow]

[Mootle]

The study of the surface temperatures is of interest for the local vicinity (to be expected according to fluid dynamics,) but unlikely to be a significant global factor, since the energy being extracted by wind turbines is negligible compared with the renewable power provided by weather systems.

However, it is conceivable that local weather patterns could be affected by these modest changes. The effects of even a slightly reduced pressure (on the leeward side of a large turbine array,) on cloud burst and increased local surface air temperatures owing to reduced air velocity could have a noticeable effect. This would all be difficult to prove given the inherently chaotic nature of weather systems.

[Mr. F]

"The study of the surface temperatures is of interest for the local vicinity (to be expected according to fluid dynamics,) but unlikely to be a significant global factor..."

The windturbines themselves will not have the power to directly affect or effect a global change but small local changes can have wider, possibly global effects.

An urban heat island can not only alter the weather of a city but also the area outside. So any change in one area can have a knock on effect on another. Will this happen to areas where wind farms are located? Possibly, but any change may only be seen or recorded if the wind farm is on the very large scale. Even then, it may just get blamed on "climate change".

You also have to wonder what the effect will be out at sea from large scale offshore installations. Could you actually site them in an area that could interfere with tropical storm formations?

[Mootle]

"The study of the surface temperatures is of interest for the local vicinity (to be expected according to fluid dynamics,) but unlikely to be a significant global factor..."

The windturbines themselves will not have the power to directly affect or effect a global change but small local changes can have wider, possibly global effects.

An urban heat island can not only alter the weather of a city but also the area outside. So any change in one area can have a knock on effect on another. Will this happen to areas where wind farms are located? Possibly, but any change may only be seen or recorded if the wind farm is on the very large scale. Even then, it may just get blamed on "climate change".

You also have to wonder what the effect will be out at sea from large scale offshore installations. Could you actually site them in an area that could interfere with tropical storm formations?

Contrary to interfering with tropical storm formation, a v.large scheme would be more likely to promote the formation of weather systems owing to the increased surface temperature on the leeward side of the array. However, this would be unlikely since storm systems tend to dwarf even the biggest of commercial wind developments.