What Will Happen To The Atmosphere It Will Be Continued To Be Depleted?

What will happen to the atmosphere it will be continued to be depleted?

If in any case, the atmosphere becomes depleted and eventually gone (which is highly unlikely to happen) several devastating effects will happen.

Animals will suffocate to death. All animals depend on the oxygen in the air. If the atmosphere will be depleted, then there will be no oxygen for animals, causing them to suffocate to death.
Plants will dry up. With no atmosphere shielding us from harmful UV rays, all plants will have their water evaporated from them; withering in the process and worse, burn under the intense heat of the sun.
Earths oceans and freshwater would evaporate. The unfiltered heat of the sun will eventually evaporate all of the water on earths surface. This includes the waters trapped in the glaciers.
Ultimately, all life on Earth would seize. Life on Earth is only possible due to the existence of water. If theres no water (because it evaporated), then there would be no place for life on Earth. Earth would eventually become what is Mars now; an arid planet that only has traces of its thriving past.

For more information about Earths atmosphere, you may click the links below: