I think it’s a fair argument that measuring temps in the middle of urban areas does not produce the most reliable data. The people saying it’s a conspiracy are clearly wrong, but the people saying the data is iron-clad and as reliable as Newton’s laws are also full of it.
I run my own weather monitoring equipment as a hobby and throw it in a time series database and see completely different results in air temperature, +/- a few degrees based on what side of the yard the measurement is taken on.
In a world where we are splitting hairs over 1-2c the microclimates present in an urban area matter. Things like reflections, landscaping, buildings, the presence or reduction of haze from local pollution and a million other factors make this data super dirty. And not only is the problem collecting reliable data in the present, but correcting data that was taken 30, 40, or 50 years ago with less sophisticated technology.
> I think it’s a fair argument that measuring temps in the middle of urban areas does not produce the most reliable data.
It was absolutely a fair point 30 odd years ago when it was first seriously raised and hammered in a number of sponsered AGW denialists blogs.
It was a serious enough point that an American climate skeptic physicists looked very hard and seriously at the data to determine if this was a valid argument against the claims of rising tempreture some 16+ years ago (IIRC). *
The result of that, and many other such studies, was that climate scientists were handling geospatial tempreture data correctly and not overweighting the tempreture of large non urban areas with readings from small constrained urban areas.
Today we are more certain given the constellation of MODIS and other satellites that continuously orbit the planet every hour and a half in precessing paths that cover the globe and return both ground level and atmosphereic depth tempreture measurements.
> I run my own weather monitoring equipment as a hobby
Good on you. I recall the instructions given to us in 1980 when setting official Bureau Met weather stations all across Australia and how to standardise and normalise instrument placement. In high school and university mathematics we also looked at the central limit theorem and the differences between single readings and pooled readings, etc.
* This was a particularly famous and well documented bit of climate debate history in the USofA theatre, I leave you to look up the details. FWiW it was "debunked" multiple earlier times, eg in Geophys Letter 1999 [1] and ranks as a standing oft repeated "climate myth" [2]
I run my own weather monitoring equipment as a hobby and throw it in a time series database and see completely different results in air temperature, +/- a few degrees based on what side of the yard the measurement is taken on.
In a world where we are splitting hairs over 1-2c the microclimates present in an urban area matter. Things like reflections, landscaping, buildings, the presence or reduction of haze from local pollution and a million other factors make this data super dirty. And not only is the problem collecting reliable data in the present, but correcting data that was taken 30, 40, or 50 years ago with less sophisticated technology.