How, exactly, are adjustments made for the urban heat island effect in temperature measurement since 1880?

The earth temperature since 1880 has supposedly risen 1.8 degrees since 1880. This measurement has partially been achieved by hundreds of weather stations around the world. I've been asking how adjustments are made to this 1.8 degree figure when the urban island effect is a factor. People here have been... show more The earth temperature since 1880 has supposedly risen 1.8 degrees since 1880. This measurement has partially been achieved by hundreds of weather stations around the world.

I've been asking how adjustments are made to this 1.8 degree figure when the urban island effect is a factor. People here have been telling me that "adjustments" are made, but these people never give me any specifics.

Do they subtract 1/10th of a degree when a one building is added around a weather station? Is it 2/10th degrees for two buildings? What if the building is taller than average? Do they subtract 15/100th of a degree? How, exactly, does that science work?
0