Copy FT and publish extent of emissions (6,9)
I believe the answer is:
carbon footprint
'extent of emissions' is the definition.
'carbon footprint' can be an answer for 'emissions' (I've seen this before). I am not certain of the 'extent of' bit.
'copy ft and publish' is the wordplay.
'copy' becomes 'carbon' (as in a carbon copy).
'ft' becomes 'foot' (synonyms).
'and' means one lot of letters go next to another.
'publish' becomes 'print' (synonyms).
'carbon'+'foot'+'print'='CARBON FOOTPRINT'
Can you help me to learn more?
(Other definitions for carbon footprint that I've seen before include "emission level" , "personal effects?" , "emissions" , "From measure of energy usage" .)