The satellite temps actually adjust for urban heat islands.
From memory - they measure air temp at more than 10,000 feet, which nullifies most of the increase.
Also, the satellites scan the entire globe, so urban heat islands make up just a fraction of 1% of the temp samples.
However - urban heat islands do have a huge impact on land temp averages, because a huge percentage of those temps come from urban instruments.
Good summary. Satellite global average temperatures are only ones that are worth reviewing.
But they can go no earlier than Nov 1979.