To ameliorate is to improve. To pejorate is to worsen. So in this case, you would have to look at whether the connotative meaning of the word "doom" has worsened or gotten better. My best guess is that it has probably worsened, so it would be pejoration.
amelioration
The opposite of pejoration (worsening) would be amelioration (building, strengthening).
surly
The word "surly" is used to describe a person who is bad-tempered or extremely unfriendly. Such a person would be said to have an abrasive personality and is therefore difficult to get along with.
Words often change their meanings over time. When a word's definition becomes more negative, that is called pejoration. Some examples are:Silly - Originally meant "blessed; fortunate." Now means, "foolish; nonsensical; stupid."Villain - originally meant "farmhand" (living in a villa i.e. country house.) Then it came to mean "low-born; low-class." Now it means "evil-doer; bad-guy."Profane - originally a neutral word meaning "anything outside the building of a church." (for example, praying in your house would have been "profane."). Now it means "sinful, evil."Pagan - originally meant "someone who lived in the country." Now it means "someone who doesn't believe in God; savage; barbarous." (The same change in meaning happened to the word "heathen.")Doom - originally meant "judgment; determination." Now it means "impending catastrophe; death; destruction." (The original meaning of doom is still retained in the words "freedom" and "wisdom" meaning "judged to be free" and "judged to be wise.")Fatal - originally meant "caused by fate/destiny." Now it means "causing death; lethal."The opposite process of pejoration is amelioration. Under amelioration, a word's definition becomes more positive over time. This is much less common (in English at least). One example:Nice - originally meant "foolish." Now it means "kind." (Of course, equating kindness with foolishness might be - in some people's opinions - a form of pejoration itself.)
Is it because the passengers were stranded in an airport that Matt became quite surly?
No, the word "surly" is not an amelioration. It typically has a negative connotation, meaning bad-tempered or unfriendly. An amelioration is a process where a word's meaning evolves to become more positive over time.
The opposite of pejoration (worsening) would be amelioration (building, strengthening).
Ameliorate
it is generalization..
The process of a word gaining a negative meaning is called pejoration. This typically happens when a word's original neutral or positive connotation shifts over time due to cultural, social, or linguistic changes. The evolution of language and usage patterns can contribute to this shift in a word's meaning.
Pejoration
He was surly
a surly waiter....
AMELIORATION
The surly man behind the desk was most unhelpful
surly
Anna was so surly because her bags were black and she was talking in a rude mean, way