How did they measure the global air surface temperature in 1850 and how do they measure it today?No it's not, however many times you say it is, and that is a slightly more silly claim than those that say we have already exceeded 1.5 Deg C - at least they are slightly closer to the true value and we have had a year where it exceeded 1.5 Deg C recently.
Here is a graph of 5 year averages
View attachment 61766
Global Climate Highlights 2024 | Copernicus
This section looks at the global Climate Indicators for which data are available for all or part of 2023. For more details on each, visit the respective Climate Indicator page. The page will be updated in stages, as data become available.climate.copernicus.eu
Incidentally the equilibrium climate sensitivity for a doubling of CO2 is 3 Deg C (range 2.5 Deg C to 4.5 Deg C)
After a 25 year career in measuring stuff and analysing data, when I see things like that, the first question I ask is about the measurement system. Was there a change to the measuring device? Is it measuring in the same way? Is the data sample being measured representative of what it was before? and things like that. 9 times out of ten, when things looked bad, they weren't. We spent a lot of time analysing data measurement systems to ensure that the results were reliable, repeatable and reproduceable.
Whenever I was set improvement targets by the boss, I could always exceed them without changing anything other than the data collection system. That was easy because I was in charge of collecting the data.
All I can say is that in my lifetime with my own measurement systems, I've seen no change in the weather and no sea level rise. I can remember all sorts of extreme weather. 1974/75 in Glasgow, it rained every day for 97 days in a row. In 1960 we had deep snow that lasted 3 months. In 1964, we had 104 mph winds in Southend. In 1975 in Glasgow, the sun came out in March and didn't go out until September. In 1976, when I went fishing in the River Wey, normally 30ft wide and 6ft deep, I arrived to find it empty. It was so hot in Guildford that I couldn't stand it, so I had to return to Glasgow. These days seem pretty calm by those standards.
I'm going to make a prediction. Within the next couple of years, this whole CO2 thing will be exposed as a hoax, then they'll switch to something else, like NO2, NO or rubber particles.