I am going to keep this very simple. The Urban Heat Effect does not affect nearby areas and does not contribute to global warming, but the IPCC insists on measuring it.
Urban areas are warm due to increased area of thermal mass such as pavements and heat sources such as air conditioners and industrial plants. This is known as the urban heat island (UHI) effect.
Urban temperatures over the last 100 years typically look like this:
Rural temperatures in the same area over the last 100 years typically look like this:
Note that the urban heat trends have no effect on the rural surroundings and thus no effect on the climate in general. These measurements should have been discarded, but the IPCC includes them as contributing to global warming.
Graphs came from the Applied Information System website:
You can see more comparisons of rural and urban heating trends here.
If you look at the two sets of graphs it becomes apparent that urban areas do not affect the temperature trends of the undisturbed rural environment.
These urban measurements are not measuring climate change, they are measuring ‘human energy production’.
If we were serious about measuring temperature trends of the earth in terms of global warming and cooling, we would completely disregard any urban measurements because they have no effect on the global climate.
The IPCC has "adjusted" the urban measurements and still includes them in their computer model. They are including heat from thousands of local heat sources even though these do not affect climate change.
Here are two videos which may give you some insight into the urban heat effect. The first is entertaining and factual. The second is just factual.
So why is the urban heat effect such a big deal?
Many MMTS stations which were in rural areas are now in urban areas. Even those in rural areas have undergone changes and may no longer be useful. The article "How not to measure temperature" describes an all too typical degradation of a measurement site.