Chemical agent to alter this worrying trend? (7,6)

I believe the answer is:

climate change

'this worrying trend?' is the definition.

'chemical agent to alter' is the wordplay.
'to alter' indicates an anagram.
'chemical'+'agent'='chemicalagent'
'chemicalagent' anagrammed gives 'CLIMATE CHANGE'.

(Other definitions for climate change that I've seen before include "Effect of 1" , "global warming" .)

I've seen this clue in The Times.

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