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From reading articles and the such it is clear that other planets such as Jupiter have storms that lasts months over months. However on Earth, storms last much shorter. In fact, the longest storm was Typhoon John which lasted a mere 31 days. Such long storms are commonly found on other planets. So why don't we have long storms?

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  • $\begingroup$ Would be very useful to the question to include specific examples. Know of Jupiter's Great Red Spot (and Little Red Spot). So occurs on Gas Giants (also Saturn/Uranus/Neptune). Think that may be reasonably explained. But if there are such storms on other terrestrial planets (Mercury/Venus/Mars), that changes it a bit. So if you don't mind and can give us more background, would be great for all :-) $\endgroup$ – JeopardyTempest Jul 24 '17 at 2:54
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The main driving force for storms to form at all are the equator-pole temperature gradients. The main reason for them to stop is friction between the lower atmosphere and earth's surface. This friction counteracts geostrophic balance (the balance between the pressure gradient and the coriolis force). Longer storms can only sustain themself through latent heat release, which can act as a secondary driver (and is the reason that Hurricanes/Typhoons can last rather long). However, at the latest at landfall this mechanism stops and the storm will decay. On gas-planets, however, there is no surface, therefore friction is much less (only the friction between different layers of the atmosphere, which is much less). Once a storm develops, with a low pressure centre, there is no (or hardly) any friction which counteracts geostrophic balance. This allows the storms to exist much longer.

As to other non-gas planets: Mars and Mercury have a very thin atmosphere, therefore, as far as I know, there is no weather as on earth anyway. As for Venus, which has an atmosphere, I do not know.

Note that also on Earth, some weather circulations last much longer than the couple of days that storms last, for example the polar vortex, which lasts the whole winter (and is far away from the earths surface). Especially if you compare the gas-planets, you might also see them as "storms" in the wider sense.

references:

(lack) of atmospheres on Mars and Mercury: https://en.wikipedia.org/wiki/Atmosphere_of_Mars, https://en.wikipedia.org/wiki/Atmosphere_of_Mercury

no surface on Jupiter: https://en.wikipedia.org/wiki/Atmosphere_of_Jupiter

disturbance of geostrophic flow due to friction: https://en.wikipedia.org/wiki/Ageostrophy

formation of storms in general: "An Introduction to Dynamic Meteorology - James R. Holton", Chapter 9, and 11

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  • $\begingroup$ Excellent answer, could you add some references though? $\endgroup$ – L.B. Jul 24 '17 at 20:13
  • $\begingroup$ To finish your thought, when geostrophic balance is maintained, pressure/temperature gradients are sustained. The friction causes the imbalance to diminish/fill in. Do note that significant latent heat release can maintain long after TC landfall (and is a significant fuel for many mid-latitude storm systems as well). Just because the storm isn't over water doesn't mean it doesn't have a moist fetch. And cut-off lows, monsoon troughs, and thermal lows all persist long periods of time due to continued support by their mechanisms. $\endgroup$ – JeopardyTempest Jul 26 '17 at 19:49
  • $\begingroup$ Also, unless you know something about Dr. Holton's family (or the textbook company) altering the copyright recently that I don't, please don't link to somebody's protected work. Just because some university in Brazil opted to copy it and distribute it illegitimately doesn't mean we should. The reference/info is still valid, just remove the link to pirated reading. I'm the biggest supporter of open information and textbooks, but that's their work and they have the right to require payment for such if they so choose. $\endgroup$ – JeopardyTempest Jul 26 '17 at 19:54
  • $\begingroup$ But otherwise I certainly appreciate the answer, you sound like you know your fair bit on meteorology, and that's a fairly lacking discipline around these parts. There are plenty that know fair bits or dabble in it, but few who've made it their focus. So glad to see that you've come around :-) $\endgroup$ – JeopardyTempest Jul 26 '17 at 19:57
  • $\begingroup$ Thanks for pointing out that the link was dubious, I had just googled the book and didnt think about copyright infrigments. Next time I shal pay more attention before linking any books! $\endgroup$ – Sip Jul 27 '17 at 7:44

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