Kinda surprised they haven't been doing this since the 60's... What with the cold war being a thing...

They were it was just handled by the Finns prior. The weather station is just changing hands which likely happens on a semi regular basis so this isn’t a new development.

They likely have been, breathing in outside air and measuring radioxenon.

Sweden developed the SAUNA and the US has its ARSA and RASA systems, all of which have been operational since the early 2000s and likely had predecessors before then.