There have been numerous studies of the effects of changing technology and measurement methods -- even such simple things as when the daily temperature readings were taken. Just last May a previously-unexplained short term drop in temperatures in the 1940s was explained by a switch in sea surface temperature measurement techniques occurring after WWII.
Such things generate a lot of traffic.
That’s a great point. Thanks.
I appreciate the link too.
how do scientists estimate the temps from 200, 300, 500, 800 or 2000 yrs ago and determine any signifigant pattern in a planet that they claim is billions of yrs old ???
thats the part that always smacked me as obvious...