At a certain level, with enough turbines, they will effect local weather. Wind turbines act as a sort of "air brake" reducing overall wind velocity. By definition they are syphoning energy out of the wind. Just as damming up a river for hydro power effects the river, damming up the wind would have to effect weather patterns.
This is true — a colleague once calculated the temperature drop in Europe if all European energy were generated by windmills. It was a few Centigrade degrees.
It’s a matter of thermodynamics: removing energy from the wind in order to create work will result in a temperature loss of the air.
That doesn’t sound quite right, if I may say so. What causes wind is a high barometric pressure in one area and a low pressure in another and the air rushes from the high toward the low. As it rushes through a wind farm it may be deflected momentarily by a windmill blade or a “stalk of asparagus”, but once it has passed the impediment the barometric pressures are the same as ever and it rushes on again, just as before.
They show up on weather radar in some areas and look like precipitation.
Trees have the same effect.
Oh the huge manatee!
This is true — a colleague once calculated the temperature drop in Europe if all European energy were generated by windmills. It was a few Centigrade degrees.