Although atmosphere  has pressure, it is said that air pressure is made by attraction to the surface by gravity because of  pressure. There would be few people opposed to this
However, looking at the altitude distribution of gravity, the sky above 100 km and the ground surface are almost the same. Then, since the air should be holding the pressure under the force of gravity pulling, the pressure should be almost the same at 100 km above the ground surface. It is also possible to think that there is not so much air. Then, the thickness of the air for the volume of the air is made, and assuming that it is 10 km, it might sharply lower the pressure with 10 km as the boundary. Because air is dragged by gravity and accumulates on the surface.The actual atmospheric pressure gradually decreases to near 30 km, and when the air pressure exceeds 30 km, almost  atmospheric pressure becomes zero.

When I checked it on the net, there was a blog "There is no centrifugal force on the gas!" It seems to be a person who is making a vacuum pump and experimenting. There is a centrifuge that separates gas, but with a tremendous high speed rotation, it can finally separate a little difference in specific gravity. Molecules in the atmosphere are flying around 400 m / s, which is faster than the speed of sound.Because it is a person who is doing it in the end, it is persuasive. If centrifugal force has little effect on gas molecules, gravity is also the same. It is because it is equivalent principle.

The atmospheric pressure is not caused by gravity. The atmosphere is a weak positive, so it is correct that it is attracted to the minus of Earth's surface. The atmospheric pressure is created by the voltage difference in the atmosphere. Therefore, when exceeding 30 km, the voltage difference disappears, so the atmospheric pressure also becomes zero.

The voltage difference makes up the atmospheric pressure difference. In a uniform electric field, the charge placed in the electric flux line is attracted by the same force, but in the electric field with the voltage difference, the higher the voltage difference, the stronger the attractive force. The gradient of the electric attractive force appears as a pressure difference.

The atmosphere is an elastic fluid and is open system. Pushing the cylinder of the syringe, the pressure rising image is incorrect.