The chart below shows land surface weather stations (the red dots).
Temperatures in the white spaces, in that moving chart, (from 1880 to 2020) are wild guessed by government bureaucrats.
The wild guesses are required because ALL land surfaces (divided into grids) need numbers to compile a global average temperature, even those with no weather stations.
They call the guessing "infilling", because 'guessing' does not sound 'scientific' (and guessing it is not scientific').
The global average temperature in 1880 is really a wild guess, with few weather stations.
Even today, in 2020, there is far too much "infilling", and too few real measurements.
The alternative satellite temperature data also have infilling, but only a small amount over both poles.
Satellites measure in the troposphere, a never changing environment not affected by economic growth, and also where the greenhouse warming effect happens.
I believe surface temperature numbers would show more global warming if not for satellite data keeping them in 'the ballpark' (since 1979).
Satellite data since 1979 show less warming than the surface temperature "data" that make the headlines, but they are similar:
Global average temperature data before 1979 are not accurate enough for real science.
Our planet is warmer than it was in the late 1600s. We don't know exactly how much warmer. But most people like warmer -- and we know people living in the late 1600s complained about their cold climate, especially in the 1690s. That period is part of what is now called The Little Ice Age.
We should be celebrating the global warming since the late 1600s -- probably about +2 degrees C. ... but reality could be +1 degree C., or +3 degrees C. No one knows, no matter what they claim to know.
Very few temperature measuremnents were kept in the 1600s, so we only have some local numbers, such as the Central England temperature numbers below:
Climate alarmists, for mysterious reasons, claim the climate was perfect around 1750. Yet they don't even know what the climate was in 1750 !
The1750 temperature is estimated from climate proxies, not real time temperature measurements using thermometers. CO2 measurements in 1750 are based on bubbles in ice cores, not actual measurements of CO2 in the 1750 atmosphere. So the "climate" in 1750 is a very rough guess, but it was perfect, we are told, and don't you forget it.
Climate alarmism is junk science, not real science.
