Posts Tagged ‘convection’

[credit: NASA]

[credit: NASA]


A few weeks ago we put up a post to discuss the role of convection in the Earth’s atmosphere:
Beginner’s guide to convection cells

The introduction, linked to a short video, said:
‘When you warm air, it rises. Cool air will sink. This process of convection can lead to flows in the atmosphere, in a manner that we can illustrate [see video] on a small scale. Warm and cool air in a fish tank rise and fall; this motion is made visible by adding fog. Ultimately, the motion leads to a convection cell, with air rising, moving to the side, falling, and moving back. This heat-driven motion of air moves heat around in the atmosphere. It is also responsible for making the wind blow.’

That may have seemed straightforward to some, but a few hundred comments later controversy continues, so we’re starting a new post using this website for reference : Lapse Rate, Moisture, Clouds and Thunderstorms

(more…)

Global circulation of Earth's atmosphere displaying Hadley cell, Ferrell cell and polar cell [credit: NASA]

Global circulation of Earth’s atmosphere displaying Hadley cell, Ferrell cell and polar cell [credit: NASA]


Introducing by popular demand (?) [click to view]:
‘Convection Cells Move Air Around’ (short video) – Windows to the Universe.

When you warm air, it rises. Cool air will sink. This process of convection can lead to flows in the atmosphere, in a manner that we can illustrate [see video] on a small scale. Warm and cool air in a fish tank rise and fall; this motion is made visible by adding fog. Ultimately, the motion leads to a convection cell, with air rising, moving to the side, falling, and moving back. This heat-driven motion of air moves heat around in the atmosphere. It is also responsible for making the wind blow.

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Cue discussion by Talkshop commenters 🙂

This post arose from a discussion on another thread that seems to have started somewhere around here.

Larger version of the NASA graphic here.
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Update – a newer post (2015/06/11) can now be viewed here:
Atmospheric convection – what does it mean?
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[comments are now closed on this thread – see ‘Update’ above]