What wind are they talking about?

I'm sorry, I would need more context to answer that question accurately. Could you please provide more information about the conversation or specify what "they" refers to?

To provide a specific answer, I would need more context regarding the conversation or topic you are referring to. "Wind" can refer to the movement of air molecules in the Earth's atmosphere, but it can also have different meanings depending on the context. Please provide more details so I can assist you better.