Moritz Büsing: Systematic Error in Global Temperatures due to Weather Station Ageing
The white paint or white plastic of the housings of weather stations ages, which leads to increased absorption of solar radiation and to increased temperature measurements. This alone would be a small error. However, many different state-of-the-art homogenization algorithms repeatedly add this small value each time a weather station is renovated, renewed, or replaced, which results in a substantial systematic error.
This error occurs, because steps in the temperature data series are corrected as if they were permanent, but this is not always the case, particularly not in case of weather station ageing and renewal.
An in-depth analysis of the weather station data sets (homogenized and non-homogenized) confirmed the presence of this systematic error, proved the existence of statistically significant ageing effects, and allowed the author to quantify the size of the ageing effects.
The effect of the ageing effects on the temperature curves is quantified by adding the ageing
functions to the temperature data points in the intervals between homogenizations. This corrected data base is analyzed using the GISTEMP tool.
Here it is shown that a reduction of the temperature change between the decades 1880-1890 and 2010-2020 also reduces the objective temperature increase from 1.43 °C to 0.83 °C (Confidence Interval 95 %: [0.46 °C; 1.19 °C]).Moritz Büsing: Systematic Error in Global Temperatures due to Weather Station Ageing
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A temperature increase that is reduced from 1.43C to 0.83 C is a lot. Not only does the location of the weather station matter but also the state of the paint covering it. I wonder how much is taken into account for the changes in these factors over time?