Good grief DJ, I've actually read through your post without falling asleep for once
Funny how - meteorologically speaking, air that descends from the stratosphere and then diverges when hitting the earth's surface, is known as a High pressure system....
What is the difference then
Anything that restricts the flow of any gas or fluid must translate into back pressure. That's the bread and butter of it all. Other phenomena that exist in and around that basic concept go towards making aerodynamics the complex theory it is
I'm with crab and DJ on this one..........