I live with atmosphere turning in major EU region (6)
I believe the answer is:
iberia
'major eu region' is the definition.
(the Iberian Peninsula)
'i live with atmosphere turning' is the wordplay.
'live' becomes 'be' (synonyms).
'with' is a charade indicator (letters next to each other).
'atmosphere' becomes 'air' (synonyms).
'turning' says the letters should be written in reverse.
'air' backwards is 'ria'.
'i'+'be'+'ria'='IBERIA'
'in' acts as a link.
(Other definitions for iberia that I've seen before include "Old name for Spanish peninsula" , "European peninsula comprising Spain and Portugal" , "The peninsula incorporating Spain and Portugal" , "Where Juan possibly lives" , "Overpower, overwhelm" .)