Man made structures can cause substantial changes in microclimates. I lived in Phoenix, AZ for a few years, and the heat gain from the metal and concrete buildings and all the asphalt sometimes raised the temperature in the city 10F or more higher than in the desert. When you think of the air conditioning costs of this, not to mention the discomfort, the value of reducing pavement and mitigating heat gain from buildings becomes very apparent.
There is often a microclimate on the south side of a house, where the walls gain heat that can support something that might otherwise freeze. It can also get uncomfortably hot on the south side in warmer climates; there are pros and cons to using a structure as a microclimate.