Fresh air over northern land (4)
I believe the answer is:
iran
'land' is the definition.
(I know that Iran is a Asian country)
'fresh air over northern' is the wordplay.
'fresh' indicates anagramming the letters.
'over' means one lot of letters go next to another (in a down clue, some letters go over others).
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'air' anagrammed gives 'ira'.
'ira'+'n'='IRAN'
(Other definitions for iran that I've seen before include "Formerly Persia" , "Country of western Asia" , "Rain (anag) - country" , "Islamic republic on the Persian Gulf" , "Modern-day Persia" .)