Simple answer, yes. This is called the heat island effect.
This is caused by a number of factors:
Albedo – The amount of reflected light (including UV and IR). This generally affects radiant heat in the area.
Thermal storage/ thermal lag/ insulation (also embodied heat/energy and specific heat) – The amount of heat present materials can absorb along with the rate at which they then release said heat back into the surrounding area. This is a complicated subject known as thermodynamics which gets really nasty at this level of complexity. This generally affects convection, contact and radiant heat in the area.
Wind change – Air will tend to get compressed between and above buildings causing wind speed changes. Changes in the air temperature will greatly affect the wind. This generally affects convection in the area.
Shade and shadow – By changing or denying areas to direct light you are changing the which objects get which heat/energy going into them. this greatly affects the radiant and contact heat in the area.
Great, what does all this mean?
We are replacing existing environments with increasingly higher reflective surfaces and better thermal storage systems. So, you get more energy shared during the day; more heat. And, better energy release during the night, more heat.
Most of the existing systems either just stored more energy, used the energy, or slowly transferred it into the ground. Modern materials either reflect it onto something else or release it back into the environment as soon as the temperature outside changes below its surface temperature.
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