This time of year...

As I have been alive many catty-years now, I have seen the same things happen, at certain times of year, about three times.
I have always wondered about these things though, particularly the things that are happening right now.

I want to know why the leaves suddenly turn all different, bright colours when they have been green for so long? Why do they then start falling from the trees? I have spent many catty-hours staring up at these trees, waiting for leaves to fall so that I can pounce on them.
There are other things that fall from trees too; things that spin round and round. What are these?

Why does the air suddenly seem cleaner, and filled with more scents, when I sniff it?
I can smell smoke at this time of year, far more than at any other time, but can't think of a reason for this.

Why is the grass often sparkly in the morning? This doesn't happen as much at other times of year.

I become much more sleepy around this time too, and take far more naps. I don't mind this as I'm cosy when I'm napping and I look cute, so I get more attention. I still don't know why I nap more though?
Also, my favourite prey disappear; mice, squirrels, frogs, even bees and wasps. I don't understand, if I can just nap more why can't they? 

And humans, can you not grow fur properly? Daddy seems to put more and more warm, fluffy things round him, to go outside. I don't understand. Humans must have been designed very badly.

Oh, one more thing; why do humans have things that look frightening and fiery, and that make loud bangs and whistles? I really don't like these them. They make me want to stay inside, and they make my little catty-ears go flat against my head :( 

*What are these spinning things?