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Earth famously possesses three distinct circulation cells per hemisphere.

Now out of curiosity one could use a weather app, like windy, to display the wind structures at ground level globally, and the supposed return winds at around 250 hPa height.

When I do that, the picture is very messy and I cannot see any clear circulation cells.

I suppose, that all the other messy physics of the Earths atmosphere will overlap with the cells, but is there a time in the year or variable I can use to see the circulation cells in wind maps?
Or are they in the end just an idealised time-average, that we use to model the winds / (trade winds, famously..) and don't exist at any given time?

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  • $\begingroup$ you need vertical cross section to see circulation cells. $\endgroup$ – gansub Oct 7 '19 at 7:04
  • $\begingroup$ specifically latitude height cross section. esrl.noaa.gov/psd/data/composites/day/details.day.html $\endgroup$ – gansub Oct 7 '19 at 7:21
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    $\begingroup$ @gansub: But specifically I need the zonally averaged latitude height cross section, right? If I take only a cross-section, then I'm plotting the messy, daily variations that I see in a weather map as well. $\endgroup$ – AtmosphericPrisonEscape Oct 7 '19 at 12:03
  • $\begingroup$ The definition of Hadley cell is zonal average. As I said CDO gives you the ability to do zonal averages of netCDF wind data. $\endgroup$ – gansub Oct 9 '19 at 4:04
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    $\begingroup$ @Deditos: A perturbation analysis like in my answer here earthscience.stackexchange.com/questions/992/… , which I've also applied to the planets of the solar system in my M.Sc. thesis (the more correct Rhines scale thoough) and it works well to predict the correct order of cell numbers. I've looked at various height levels at ventusky.com, but there were no clear patterns. It might also require the right projection, or time of the year, which I've included in the question. $\endgroup$ – AtmosphericPrisonEscape Oct 9 '19 at 16:18
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Yes, the wind cells are just a toy model, where we can suppose that the homogenity of the Earth and other things. But there are other things and Earth isn't same on the all points, so the instantaneous winds don't follow their cells. Of course, it is possible (by pure statistics) that sometimes in the Earth history, the majority of the winds was aligned with their cells. But the cells are just averaged over the period of more decades and centuries.

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  • $\begingroup$ Sorry for late answer :) $\endgroup$ – User123 Mar 1 at 12:11
  • $\begingroup$ No worries, but the question was essentially already answered in the comments. $\endgroup$ – AtmosphericPrisonEscape Mar 2 at 18:59

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