Angular speed of the Earth's atmosphere

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Discussion Overview

The discussion revolves around the relationship between the Earth's atmosphere and its angular speed, particularly in the context of the Coriolis effect and atmospheric dynamics. Participants explore whether the atmosphere is stationary relative to the Earth's surface or if it moves independently, and how this affects weather patterns, such as hurricanes.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question whether the Earth's atmosphere matches the angular speed of the Earth or if it "slides" over the surface, influencing the Coriolis effect observed in weather systems.
  • One participant suggests that if the atmosphere were not spinning with the Earth, extreme winds would occur at the equator, implying a relationship between atmospheric rotation and surface speed.
  • Another participant proposes that the angular velocity of the atmosphere might vary with distance from the surface and be affected by geographical features like mountains.
  • Some argue that the atmosphere is influenced by various forces, including gravity, friction, and solar convection, and that these forces prevent it from being "attached" to the Earth's surface.
  • A participant references historical satellite measurements indicating that the upper atmosphere may rotate faster than the Earth, challenging the notion of uniform angular velocity across the atmosphere.

Areas of Agreement / Disagreement

Participants express differing views on whether the atmosphere is stationary with respect to the Earth's surface or if it rotates in sync with the Earth. There is no consensus on the exact nature of the atmospheric dynamics and their implications for weather patterns.

Contextual Notes

Some discussions reference the complexity of atmospheric circulation, including the effects of pressure gradients and differential heating, which may not be fully resolved in the conversation. The influence of surface friction and the behavior of the upper atmosphere are also noted as areas of uncertainty.

GRB 080319B
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Does the Earth's atmosphere match the angular speed of the Earth (i.e. is it stationary with respect to the Earth's surface, or is it "sliding" over the Earth's surface)? I'm trying to understand if the Coriolis effect that is creating the spiral pattern present in hurricane would be the same pattern if the hurricane was somehow "fixed" to the Earth's surface (if perhaps the water droplets could be represented by bowling balls rolling on the ground in the pattern of a low pressure system).

Is the Corliolis effect stronger for planets with greater angular speed?
 
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GRB 080319B said:
Does the Earth's atmosphere match the angular speed of the Earth (i.e. is it stationary with respect to the Earth's surface, or is it "sliding" over the Earth's surface)? I'm trying to understand if the Coriolis effect that is creating the spiral pattern present in hurricane would be the same pattern if the hurricane was somehow "fixed" to the Earth's surface (if perhaps the water droplets could be represented by bowling balls rolling on the ground in the pattern of a low pressure system).

Is the Corliolis effect stronger for planets with greater angular speed?

CE apparently works for stationary polar ice caps. Replace your bowling balls with dust and ices.

http://www.physorg.com/news195924542.html

Great Red Spot, Batman
 
Thank you for guiding me to that article. The wind at the martian ice cap is being steered/twisted by the CE as it collects and subsequently deposits ice crystals into the spiral pattern.

I was also wondering if the Earth's atmosphere matches the angular speed of the Earth? Or does the Earth "slide" underneath the atmosphere, the movement of which is driven primarily by temperature and pressure gradients and independent of interaction with Earth's surface?
 
How could you even imagine that the atmoshere is spinning 'round as though attached to the surface?? Influenced, yes .. by gravity and friction and certainly other forces (solar convection, etc) .. Were it 'attached' there's be no winds!
 
Were the atmosphere not spinning with the Earth we would experience (at the equator) winds on the order of 1000mph. So while the atmosphere may not be attached, it does spin with the same angual velocity as the earth.
 
I would have guessed the angular velocity of the atmosphere was a function of the distance from the surface with distortions around mountains.
 
tkjtkj said:
How could you even imagine that the atmoshere is spinning 'round as though attached to the surface?? Influenced, yes .. by gravity and friction and certainly other forces (solar convection, etc) .. Were it 'attached' there's be no winds!

From what I understand, the atmospheric circulation is caused by differential heating of the Earth's surface, which subsequently causes a pressure gradient in the atmosphere, and the Coriolis effect, which acts to deflect air currents moving through the pressure gradient. I don't understand why convection currents couldn't occur and drive weather patterns while the atmosphere as a whole is stationary wrt the Earth's surface?

From http://en.wikipedia.org/wiki/Wind#Cause": "Wind is caused by differences in pressure. When a difference in pressure exists, the air is accelerated from higher to lower pressure. On a rotating planet the air will be deflected by the Coriolis effect, except exactly on the equator. Globally, the two major driving factors of large scale winds (the atmospheric circulation) are the differential heating between the equator and the poles (difference in absorption of solar energy leading to buoyancy forces) and the rotation of the planet. Outside the tropics and aloft from frictional effects of the surface, the large-scale winds tend to approach geostrophic balance. Near the Earth's surface, friction causes the wind to be slower than it would be otherwise. Surface friction also causes winds to blow more inward into low pressure areas."

Integral said:
Were the atmosphere not spinning with the Earth we would experience (at the equator) winds on the order of 1000mph. So while the atmosphere may not be attached, it does spin with the same angual velocity as the earth.

Why does the Earth's atmosphere spin with the same angular speed as its surface? Purely a transference of friction from its surface?
 
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Within naive models, the entire atmosphere has the same rotational velocity - there is no drag at the top of the atmosphere and the whole block of air behaves somewhat like a rigid body attached to the earth. The question of how true this is was important back as early as the 1960s, when satellites were starting to go up, and it was important to correct for drag at the upper atmosphere. Measurements from a number of these early satellites showed that the upper atmosphere was, in fact, rotating faster than the Earth!

See, for instance, D. G. King-Hele, Planetary and Space Science, Volume 12, Issue 9, September 1964, Pages 835-853

linkinghub.elsevier.com/retrieve/pii/0032063364900443[/URL]
 
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