Questions tagged [dynamics]
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15 questions
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Why high gradient height countours or sharp curvature trough are associated with stronger divergence?
All,
The chart below from https://www.weather.gov/source/zhu/ZHU_Training_Page/Miscellaneous/Divergence/divergence.html suggests that divergence increases with the gradient of the height contours and ...
- 175
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Confusion about the horizontal pressure gradient force being equal to the gradient of the geopotential in pressure coordinates
I asked this in the physics exchange and thought I would ask here as well:
I see many sources in atmospheric dynamics express the following:
$\frac{1}{\rho}(\nabla p) = \nabla_p \phi$
For example this ...
- 163
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How can oceanic Rossby waves move from East to West?
I can find several examples of Rossby waves, mainly atmospheric, moving towards East. Is it possible that they also move towards West?
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Application of vorticity tendency equation
I have a question about the dynamics of westward propagating vortices.
In meteorology, the vorticity tendency is often used to explain the westward propagation of vortices (cyclonic circulation).
A ...
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3
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1
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When and where is the atmospheric greenhouse effect strongest?
Is the greenhouse effect stronger in the ice covered area or in the equator?
Also is it stronger during winter or summer?
I am thinking it is stronger in the Ice covered area and during winter because ...
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4
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1
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Why is potential vorticity so emphasized in technical work, but often neglected in maps on weather websites?
When I was first introduced to potential vorticity, I was told that it is a very important tool for meteorologists to learn. Sure, it solved a simple problem in dynamics, but it wasn't apparent to me ...
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Is this a valid semi-diagnostic equation for Omega?
Beginning with the Primitive equations governing atmospheric motion for a dry gas, primarily the ideal gas law, and the conservation of mass and energy, neglecting diffusivity.
$$P=\rho R T$$
$$\...
- 8,909
4
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1
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What causes variation of seabed depth relative to fixed chart datum?
Please refer to this page of coastal wiki. Quoting:
...the reconstructed overall vertical position [of the seabed] with respect to a fixed chart datum may vary by more than 10 cm from survey to ...
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Is there a distinction between gap winds and channelled flow?
I have seen gap flows mentioned in the literature, for example [Gohm et al. 2004, Zängl 2002, Mayr et al. 2007]. Whiteman 2000 defines a gap as a "major erosional opening through mountain ranges" and ...
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Tornadoes meeting with an Immovable, Unbreakable, Large Cube
What would happen to a tornado if a Large, Immovable, Unbreakable and Obsidian Cube was in its path?
The tornado is on a flat plain... but is heading towards the cube.
By large, I mean the length of ...
- 121
12
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1
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Are the "polar vortex" and "cut-off lows" over/near the Great Lakes new phenomena?
In recent years, I've heard weather reporters describe "cut-off" low pressure systems which park over Southern Ontario for days at a time. In summer months, they bring us long stretches of cool cloudy,...
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Why does Coriolis determine the rotation direction of a cyclone but not my drain?
It is a common misconception that Coriolis is responsible for the direction the water swirls down a toilet, tub or sink drain. E.g. does a toilet flush the other way in the southern hemisphere? (If ...
- 14.2k
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Why does the Northern polar vortex usually have two centers?
From http://glossary.ametsoc.org/wiki/Polar_vortex
polar vortex
A planetary-scale mid- to high-latitude circumpolar cyclonic circulation, extending from the middle troposphere to the stratosphere. ...
- 1,843
12
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1
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How is the Rossby Radius used to determine that synoptic weather systems are 1000-2000km across?
In one of his presentations, Sandy MacDonald (of NOAA and ESRL) talks about the Rossby Radius of Deformation in connection with the size of synoptic weather systems: he describes how it sets the ...
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What do quasi-geostrophic and ageostrophic mean?
I know that geostrophic flow means straight wind flow that is balanced by the pressure gradient and Coriolis forces. But what do quasi-geostrophic and ageostrophic mean specifically?
anon