This is the 3359th most frequent Russian word.
пожарах
"Пожарах" means "fires" (prepositional plural form).
Here, 'пожарах' is in the prepositional case plural, referring to the topic being discussed, which is 'fires'.
Мы говорили о пожарах в лесах.
We talked about the forest fires.
In this sentence, 'пожарах' is again in the prepositional case plural, indicating the location related to the action described.
После пожарах остались только обугленные деревья.
After the fires, only scorched trees remained.
The word 'пожарах' here is used to specify what the article is about, fitting the plural prepositional usage.