Several years ago, there was an audit of all the USA weather stations, 80% were within 20meters of an artificial heat source such as air conditioning exhausts, electrical sub stations and sewage works.
Add to this all the obvious upward adjustments of recent temperatures and the cooling of historical temperatures gives an exaggerated temperature increase.
Our BOM with their ACORNSAT11 review increased the rate of warming by 23% by cooling the past.
the US set up a set of weather stations in pristine areas that are not affected by development, here is that chart.
