The most common and most likely answer to this crossword clue is the 6 plus 7 letter word GLOBAL WARMING
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More clues leading to the result GLOBAL WARMING
- Change law or gambling could get us all heated up?
- Blog about West overwhelmed by frightful climate change
- Stirring up a brawl during twilight wanting a change in the atmosphere
- All heart in mouth about world’s foremost scary phenomenon?
- Girl having fling with member in group — situation that’s hotting up?
- WW III? China is a threat to the world
Buddy explains!

The straight part
We know that "threat to the world" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case threat to the world = global warming.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.