Can construction of an airport lead to more foggy weather?
The statement is apparently from the Introduction to Airports Design and Operations of 
Center for Air Transportation Systems Research at George Mason University.

One form of fog that is formed in airports usually is radiation (or ground) fog. As the flat open surfaces in airport are prone to cooling overnight due to thermal radiation, the air close to the surface is also cooled to the dew point. This reduces the ability of the air to hold moisture, allowing condensation and fog to occur. 

One reason for the statement may be that open areas in the airport give up their heat much quicker than urban heat islands, which does not have flat surfaces prone to thermal radiation.