He is the dev, so could do it from within the code

I'm interested by a few details here, as I'm faced with related questions in a RPG campaign I'm writing (a true, pen&paper campaign), with Aurora has the planned assistant for the global situation.
-- 1 --
What is the formula used for dust settling up? It seems 'nuclear winter' recovery is a fast process, from what I read (I mean, certainly not fast for the people dying from cold, but in a generation, dust has settled much I think)
-- 2 --
Temperature drop. How it works, compared to dust generation, I don't think it was published in the C# mechanics.