One possibility: Western Germany is more industrialized and urban, with higher population and population density. Thermal measurements in the west are more likely to be taken in urban heat islands?
Other parts of West Germany also sport lower population density (Lower Saxony in the North, Bavaria in the South).
It is absolutely astonishing how strongly human behavior (industry and metropolitan areas) influences local environmental conditions. I guess most cities may (be forced to) change radically.
https://en.wikipedia.org/wiki/Demographics_of_Germany#/media...
Other parts of West Germany also sport lower population density (Lower Saxony in the North, Bavaria in the South).
It is absolutely astonishing how strongly human behavior (industry and metropolitan areas) influences local environmental conditions. I guess most cities may (be forced to) change radically.