Let’s give the brain a workout on Hump Day 🙂

The flow of my life is rapid in Spring.
A much slower pace – Summer does bring.
I’m always changing – yet appear the same.
The taller I am, the greater my fame.
Without gravity I would not exist.
If you don’t know me, you’re lost in my mist.

So stretch your brain and try to solve this riddle. Post in the comment section below, once a correct answer has been given I will confirm.