Surprised comments picked up and published regarding desert (7)
I believe the answer is:
saharan
'regarding desert' is the definition.
'surprised comments picked up and published' is the wordplay.
'surprised comments' becomes 'ahas' (aha's).
'picked up' shows that the letters should be reversed in order.
'and' means one lot of letters go next to another.
'published' becomes 'ran' (running is a kind of publishing).
'ahas' reversed gives 'saha'.
'saha'+'ran'='SAHARAN'
(Other definitions for saharan that I've seen before include "Relating to the North African desert" , "Baking" , "Deserter" .)