Look at their longitude and latitude. Those two are on the edges of Bucharest (which is why the one that you linked was set up in the 1950s, and the other in t

Look at their longitude and latitude. Those two are on the edges of Bucharest (which is why the one that you linked was set up in the 1950s, and the other in the 1970s). The longstanding temperature station is in the center of the city. I think that what you are most likely seeing is the urban heat island effect rather than any incorrect measurements on the part of any of these stations. Areas undergoing urban expansion get hotter as they are built up. The 2013 cutoff may be a limitation of the Berkeley data in general.