There is far too much missing temperature data before 1900 for the claim of a +/- 0.1 degree C. margin of error in the stated global warming since 1880.
Most of the planet had no weather station coverage before 1900.
The global surface coverage was still low before 1920.
For sea temperature "measurements", areas outside normal shipping lanes were generally ignored, with few measurements in the Southern Hemisphere.
Using buckets and thermometers. Ha ha
You can't extrapolate accuracy, to the nearest 0.1 degree C., starting with no data for most surface grids on the planet.
The coming climate crisis alarmists promote many misleading claims:
Claimed global average temperature margin of error of +/- 0.1 degree C. since 1880
Claiming to actually know the global average temperature in the 1800s.
Claiming a theoretical water vapor positive feedback effect, tripling the alleged warming effect of CO2 alone, that has never been seen in actual temperature measurements in the past 50 years.
Using climate computer games that predict more than double the actual warming since 1979.
Over 50 years of predicting a climate crisis as the actual climate gets more moderate and more comfortable.
Promoting a single global average temperature that no one lives in, while ignoring the locations and timing of the most warming since the 1970s, such as warmer winter nights in Siberia.
Claiming future global warming will be a "climate emergency", completely unlike the mild, pleasant global warming since the 1970s, that most people have enjoyed.
Demanding the replacement of reliable sources of electric power, at great expense, with unreliable wind and solar power.
Refusing to debate climate science, rudely attacking skeptics as "science deniers", falsely claiming climate science is settled.
This all adds up to junk science used for climate change scaremongering.
How about real air pollution over many Asian cities from burning fossil fuels without modern pollution controls.
Who cares about that pollution?
Not the climate alarmists.
How about one billion people in the world with no electricity.
Who cares about them?
Not the climate alarmists.