Study of Nordic countries overlooks noise pollution of those who fly? (4)

I believe the answer is:

scan

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'study' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for scan that I've seen before include "Peruse, scrutinise" , "Read hastily" , "Skim; examine" , "Analyse a piece of verse for metre" , "Examine (to transmit)" .)

I've seen this clue in The Independent.

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