Atmosphere around capital city cold and extremely tense (7)
I believe the answer is:
Here is my best explanation:
'atmosphere' is the definition.
(I've seen this before)
'around capital city cold and extremely tense' is the subsidiary indication.
'around' means one lot of letters goes inside another.
'capital city' becomes 'lima' (I've seen this before).
'cold' becomes 'c'.
'and' is a charade indicator (letters next to each other).
'extremely' suggests removing the centre.
'tense' with its centre taken out is 'te'.
'lima' placed into 'cte' is 'climate'.
(Other definitions for climate that I've seen before include "Prevailing trend", "Long-term prevalent weather conditions", "Prevailing public attitude", "Weather conditions of a region", "Atmosphere", "Prevailing state", "Mail, etc (anag.)", "The regular weather conditions of a region", "General weather conditions in an area" and "Weather in general".)