This was originally posted in r/NoStupidQuestions, but someone suggested I post this here, too.
I was looking at Köppen climate maps and noticed [this climate map of Germany](https://commons.wikimedia.org/wiki/File:Germany_map_of_K%C3%B6ppen_climate_classification.svg), which showed a region of subtropical climate in the southwest of Germany, near the border with Switzerland. I found that the map of Germany was from [this climate map of the world](https://commons.wikimedia.org/wiki/File:World_K%C3%B6ppen_Classification_(with_authors).svg), which in turn came from [this paper](https://hess.copernicus.org/articles/11/1633/2007/hess-11-1633-2007.pdf).
I read through the paper but it never mentions the subtropical area in Germany, despite showing it in their maps. I also found it unusual because this is the only Köppen climate map I have ever seen that shows any areas of subtropical climate in Germany.
I normally would have dismissed this map because it conflicts with all other climate maps, but the source seems pretty reliable, which leads me to my current dilemma.
Why does this map show a subtropical climate in Southwest Germany? Was it just a mistake, or is there something I wasn’t aware of about the climate of Germany?
2 comments
It’s correct (the map). It has to do with Lake Konstanz:
https://www.bodensee.eu/en/where-to-travel/lake-constance-cities/konstanz_topcity241
The difference between Cfa and Cfb is only that in Cfa climate the warmest month has a mean temperature of 22 °C or higher, while in Cfb all months’ mean temperatures stay below that threshold. It looks like the climate in this area of Germany just barely meets the conditions for Cfa, see e.g. the [climate of Konstanz](https://de.wikipedia.org/wiki/Konstanz#Klima).