<p>The atmospheric height is a difficult concept to explain to someone new. I've learned that the best way to talk about it is to specify it parenthetically. In other words, it is the geopotential height (of the 500 hPa isobaric surface).</p>
<p>The 5.5 km estimate is just that- an estimate or rule of thumb. It goes down in areas of low pressure (and when the average column of air is cool) and goes up in areas of high pressure (and when the average column of air is warm). So while those who may be very particular with their numbers may object, it is <em>roughly</em> about 50% of the pressure and 50% of the mass. So you are roughly correct. If you go up halfway through the atmosphere, you still have half of the atmosphere weighing down on you. I'd give that a correct on an exam.</p>
<p>Generally, as you go up into the atmosphere, you have less atmosphere weighing down on you. That's why people need oxygen masks on Mt. Everest and some higher altitude flights are pressurized.</p>
<p>Now my experience is that students struggle more with the spatiotemporal variations (as I stated in the beginning). But really it is the pressure varying in time and space, and plots of the geopotential heights of isobaric surfaces showing how far up until you reach that pressure. And the key to this is the <a href="https://en.wikipedia.org/wiki/Barometric_formula#Derivation" rel="nofollow noreferrer">Barometric formula</a>, used interchangeably with the <a href="https://en.wikipedia.org/wiki/Hypsometric_equation#Derivation" rel="nofollow noreferrer">Hypsometric equation</a> and hydrostatic equation. Synoptic scale variations in the geopotential height of isobaric surfaces are often attributable to the <a href="https://en.wikipedia.org/wiki/Scale_height" rel="nofollow noreferrer">scale height</a>.</p>

CC BY-SA 4.0
2024-02-19T19:30:05.643Z
2024-02-19T19:30:05.643Z
BarocliniCplusplus
<p><strong>Not exactly</strong></p>
<p>The medium atmospheric pressure at sea level is 1013.25 hPa. 1013.25 - 500 = 513.25 hPa, which is close to 500 hPa, but is not the same.
The medium atmospheric pressure at sea level is a universal constant, not dependent on the place. Oh, sorry, of course, it IS dependent, but only if we count with precision, far than unreachable by meteorology medium numbers.</p>

CC BY-SA 4.0
2024-01-19T18:03:59.373Z
2024-01-19T18:03:59.373Z
Gangnus
<p>I am currently struggling to really understand geopotential height on a conceptual level.<br />
Let's say we look at the geopotential height of 500hPa over Europe, where it is usually around 5.5km.<br />
Does it mean that at a height of 5.5km the remaining air column (above 5.5km) exerts a pressure of 500hPa?</p>

<meteorology>
Explanation of geopotential height
AkariYukari
# Explanation of geopotential height

(Asked by: username_0 on 2024-01-19)

I am currently struggling to really understand geopotential height on a conceptual level.  
Let's say we look at the geopotential height of 500hPa over Europe, where it is usually around 5.5km.  
Does it mean that at a height of 5.5km the remaining air column (above 5.5km) exerts a pressure of 500hPa?

**Tags:** meteorology


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## 2 answers

### Answer by username_1 on 2024-02-19. Score: 3 | Accepted answer

The atmospheric height is a difficult concept to explain to someone new. I've learned that the best way to talk about it is to specify it parenthetically. In other words, it is the geopotential height (of the 500 hPa isobaric surface).

The 5.5 km estimate is just that- an estimate or rule of thumb. It goes down in areas of low pressure (and when the average column of air is cool) and goes up in areas of high pressure (and when the average column of air is warm). So while those who may be very particular with their numbers may object, it is *roughly* about 50% of the pressure and 50% of the mass. So you are roughly correct. If you go up halfway through the atmosphere, you still have half of the atmosphere weighing down on you. I'd give that a correct on an exam.

Generally, as you go up into the atmosphere, you have less atmosphere weighing down on you. That's why people need oxygen masks on Mt. Everest and some higher altitude flights are pressurized.

Now my experience is that students struggle more with the spatiotemporal variations (as I stated in the beginning). But really it is the pressure varying in time and space, and plots of the geopotential heights of isobaric surfaces showing how far up until you reach that pressure. And the key to this is the [Barometric formula](https://en.wikipedia.org/wiki/Barometric_formula#Derivation), used interchangeably with the [Hypsometric equation](https://en.wikipedia.org/wiki/Hypsometric_equation#Derivation) and hydrostatic equation. Synoptic scale variations in the geopotential height of isobaric surfaces are often attributable to the [scale height](https://en.wikipedia.org/wiki/Scale_height).


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### Answer by username_2 on 2024-01-19. Score: 0

**Not exactly**

The medium atmospheric pressure at sea level is 1013.25 hPa. 1013.25 - 500 = 513.25 hPa, which is close to 500 hPa, but is not the same.
The medium atmospheric pressure at sea level is a universal constant, not dependent on the place. Oh, sorry, of course, it IS dependent, but only if we count with precision, far than unreachable by meteorology medium numbers.


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