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A while ago, I learned about field of exometeorology (the study of other planets ' atmospheres) which fascinates me. In particular, I read about thunderstorms on Venus, e.g. about the results from ESA's Venus Express Mission in 2006, or according to Universetoday.com: Lightning Storms on Venus Similar to Those On Earth:

“We have analyzed 3.5 Earth-years of Venus lightning data using the low-altitude Venus Express data, which is about 10 minutes per day,” Russell said. “By comparing the electromagnetic waves produced at the two planets, we found stronger magnetic signals on Venus, but when converted to energy flux we found very similar lightening strength,” said Russell. Also it seems that lightning is more prevalent on the dayside than at night, and happens more often at low Venusian latitudes where the solar input to the atmosphere is strongest.”

This is mainly a statement about the intensity and time distribution of the lightning on Venus. I am now wondering whether there is more known about the mesocale convective systems on Venus. My search gave me the impression that there is not much literature on that topic (yet), or am I mistaken?

The main question I am after: How long do storm cells on Venus last? Is any mean or median known? Can thunderstorm systems live for multiple (Venus) days?

References

Although I did not find any answer to my question, here some references I found:

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Independent observation led to the conclusion that lightning is prevalent on Venus. Electromagnetic signals detected by the 4 Venera landers explained the main cause of lightning on Venus. Venera 9 spectrometer detected a lightning stroke. The Pioneer plasma wave instrument detected waves which explained lightning might be at low altitude. VLF observation suggested that lightning is a intra-cloud phenomenon which is more common in the afternoon and evening time and the occurrence rate is more as compared to Earth. Venera 11, 12, 13 14 were equipped to detected magnetic signature(acoustic data were also obtained from V11 and V12).

Lightning on Venus occur from strong convective cumulus cloud and occasionally from dust storms and volcanic clouds. The clouds may vary in altitude from few km to 30 km . Lightning on Venus occur due to two distinct forms: cloud-to-ground discharge and intra-cloud discharge. Such discharge occur when electric field exceeds from 106 V/m in wet air to 3 $\times$ 106 V/m in dry air. Cloud to ground discharge carry current from 200-300 A which increase every 50-100m, travelling at a velocity of 1.5 $\times$ 106 m/s which followed with a return stroke with velocity 0.6 $\times$ 108 m/s carrying 10-20 kA which decays in about 20-50 us. There are 3 or more stroke in one flash separated by 40 ms and lasts 0.2 s.

Discharges within clouds are 2 to 4 times more frequent than that of cloud-to-ground discharge and carry currents upto 4kA but they generate less energy(4.5 $\times$ 108 J in cloud-to-ground discharge). Number of discharges on Venus is more than that of Earth. Over 7000 discharges occurs on Venus per day You can check the details and observation in ref.1 and ref.3

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Fig. 1 Venusian atmosphere where lightning is most likely to occur

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Fig.2 Magnetic field due to intra-cloud discharge (altitude 50 km)

References

  1. Venus lightning by Russell, C. T., Space Science Reviews, vol. 55, Jan-Feb 1991, p. 317-356. (link and the author's paper here)
  2. Russell, C.T. et.al. (2011). Venus lightning: Comparison with terrestrial lightning. Planetary and Space Science - PLANET SPACE SCI. 59. 965-973. 10.1016/j.pss.2010.02.010.
  3. Lorenz, R.D. Lightning detection on Venus: a critical review. Prog Earth Planet Sci 5, 34 (2018). https://doi.org/10.1186/s40645-018-0181-x
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  • $\begingroup$ Your answer is confirming my gut feeling that mesoscale atmospheric systems powered by Sun are dependend on the time of the day of the respective planet. Differently put: Vulcanic activity does not seem to be the major cause for lightning on Venus, but the flashes are likely to be mostly convectively generated. $\endgroup$ – B--rian Dec 16 '20 at 9:50
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    $\begingroup$ @B--rian yes the authors has put forward the conclusion that most of the discharges occur due to intra-cloud movements. Lightning due to volcanism has been proposed but hasn't been proved yet. Maybe in the future, they will prove that volcanism also play a role in the discharges. $\endgroup$ – Nilay Ghosh Dec 16 '20 at 13:31

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