Atmospheric Pressure: Definition & Effects

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Thermosphere: Definition, Facts, Composition & Temperature

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:00 Definition
  • 1:17 Altitude
  • 1:58 Temperature
  • 2:37 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed Audio mode

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Jeff Fennell

Jeff has a master's in engineering and has taught Earth science both domestically and internationally.

Atmospheric pressure is around us all of the time. The air you are breathing has weight, and although it doesn't weigh a lot, there is a lot of it around. This lesson will cover atmospheric pressure and its effects.


It can be odd to think of air as having weight - after all it doesn't feel like it! But the air is full of molecules and though extremely light, they do have weight. The more air you have above a thing, the more weight that thing will feel.

Atmospheric pressure is the weight of the atmosphere on a surface. The units for atmospheric pressure are conveniently known as atmospheres (atm) and the average pressure at sea level is set at 1 atmosphere (atm).

On average, the weight of the atmosphere on a square inch is 14.7 pounds at sea level. This means if you were to extended a 1-inch column from sea level to the edge of our atmosphere, all the gases inside would weigh 14.7 pounds. Another way to think about it is, if you put your hand out, there is more or less 175 pounds of atmosphere weighing down on it, and a standard 8.5 x 11 piece of paper has over 1300 pounds weighing down on it.

So why doesn't it crush us? Luckily we have evolved to deal with it and not notice it. In fact, we would have big problems if there wasn't all that pressure keeping us together.


The atmospheric pressure at any given point depends on two factors:

  • Altitude - the height of a thing in relation to sea level
  • Temperature - the intensity of heat

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account