A new paper suggests that wind turbines, installed broadly, might actually change the climate themselves just by disrupting the normal flow of the wind:
In a paper published online Feb. 22 in Atmospheric Chemistry and Physics, [the MIT researchers] Wang and Prinn suggest that using wind turbines to meet 10 percent of global energy demand in 2100 could cause temperatures to rise by one degree Celsius in the regions on land where the wind farms are installed, including a smaller increase in areas beyond those regions.
Their analysis indicates the opposite result for wind turbines installed in water: a drop in temperatures by one degree Celsius over those regions....
In the analysis, the wind turbines on land reduced wind speed, particularly on the downwind side of the wind farms, which reduced the strength of the turbulent motion and horizontal heat transport processes that move heat away from the Earth’s surface. This resulted in less heat being transported to the upper parts of the atmosphere, as well as to other regions farther away from the wind farms. The effect is similar to being at the beach on a windy summer day: If the wind weakened or disappeared, it would get warmer.