Atmospheric conditions and so on upset round capital city (7)
I believe the answer is:
climate
'atmospheric conditions' is the definition.
(I've seen this before)
'and so on upset round capital city' is the wordplay.
'and so on' becomes 'etc' ('etc.' can be a synonym of 'and so on').
'upset' is a reversal indicator.
'round' means one lot of letters goes inside another.
'capital city' becomes 'lima' (I've seen this before).
'etc' back-to-front is 'cte'.
'cte' going around 'lima' is 'CLIMATE'.
(Other definitions for climate that I've seen before include "The regular weather conditions of a region" , "General weather conditions in an area" , "Cite Mal (anag.)" , "Feeling" , "Weather etc" .)