Small thunderstorms may add up to massive cyclones on Saturn

June 15, 2015 by Jennifer Chu
The rings of Saturn and its north polar vortex. Credit: Caltech/Space Science Institute

For the last decade, astronomers have observed curious "hotspots" on Saturn's poles. In 2008, NASA's Cassini spacecraft beamed back close-up images of these hotspots, revealing them to be immense cyclones, each as wide as the Earth. Scientists estimate that Saturn's cyclones may whip up 300 mph winds, and likely have been churning for years.

While cyclones on Earth are fueled by the heat and moisture of the oceans, no such bodies of water exist on Saturn. What, then, could be causing such powerful, long-lasting storms?

In a paper published today in the journal Nature Geoscience, atmospheric scientists at MIT propose a possible mechanism for Saturn's polar cyclones: Over time, small, short-lived thunderstorms across the planet may build up , or spin, within the atmosphere—ultimately stirring up a massive and long-lasting vortex at the poles.

The researchers developed a simple model of Saturn's atmosphere, and simulated the effect of multiple small thunderstorms forming across the planet over time. Eventually, they observed that each thunderstorm essentially pulls air towards the poles—and together, these many small, isolated thunderstorms can accumulate enough atmospheric energy at the poles to generate a much larger and long-lived cyclone.

The team found that whether a cyclone develops depends on two parameters: the size of the planet relative to the size of an average thunderstorm on it, and how much storm-induced energy is in its atmosphere. Given these two parameters, the researchers predicted that Neptune, which bears similar polar hotspots, should generate transient polar cyclones that come and go, while Jupiter should have none.

Morgan O'Neill, the paper's lead author and a former PhD student in MIT's Department of Earth, Atmospheric and Planetary Sciences (EAPS), says the team's model may eventually be used to gauge atmospheric conditions on planets outside the solar system. For instance, if scientists detect a cyclone-like hotspot on a far-off exoplanet, they may be able to estimate storm activity and general atmospheric conditions across the entire planet.

"Before it was observed, we never considered the possibility of a cyclone on a pole," says O'Neill, who is now a postdoc at the Weizmann Institute of Science in Israel.

"Only recently did Cassini give us this huge wealth of observations that made it possible, and only recently have we had to think about why [polar cyclones] occur."

O'Neill's co-authors are Kerry Emanuel, the Cecil and Ida Green Professor of Earth, Atmospheric and Planetary Sciences, and Glenn Flierl, a professor of oceanography in EAPS.

Beta-drifting toward a cyclone

Polar cyclones on Saturn are a puzzling phenomenon, since the planet, known as a gas giant, lacks an essential ingredient for brewing up such storms: water on its surface.

"There's no surface at all—it just gets denser as you get deeper," O'Neill says. "If you lack choppy waters or a frictional surface that allows wind to converge, which is how hurricanes form on Earth, how can you possibly get something that looks similar on a gas giant?"

The answer, she found, may be something called "beta drift"—a phenomenon by which a planet's spin causes small thunderstorms to drift toward the poles. Beta drift drives the motion of hurricanes on Earth, without requiring the presence of water. When a storm forms, it spins in one direction at the surface, and the opposite direction toward the upper atmosphere, creating a "dipole of vorticity." (In fact, videos of hurricanes taken from space actually depict the storm's spin as opposite to what's observed on the ground.)

"The whole atmosphere is kind of being dragged by the planet as the planet rotates, so all this air has some ambient angular momentum," O'Neill explains. "If you converge a bunch of that air at the base of a thunderstorm, you're going to get a small cyclone."

The combination of a planet's rotation and a circulating storm generates secondary features called beta gyres that wrap around a storm and essentially split its dipole in half, tugging the top half toward the equator, and the bottom half toward the pole.

The team developed a model of Saturn's atmosphere and ran hundreds of simulations for hundreds of days each, allowing small thunderstorms to pop up across the planet. The researchers observed that multiple thunderstorms experienced beta drift over time, and eventually accumulated enough atmospheric circulation to create a much larger cyclone at the poles.

"Each of these storms is beta-drifting a little bit before they sputter out and die," O'Neill says. "This mechanism means that little thunderstorms—fast, abundant, but not very strong thunderstorms—over a long period of time can actually accumulate so much angular momentum right on the pole, that you get a permanent, wildly strong cyclone."

Next stop: Jupiter

The team also explored conditions in which would not form polar cyclones, even though they may experience thunderstorms. The researchers found that whether a polar cyclone forms depends on two parameters: the energy within a planet's atmosphere, or the total intensity of its thunderstorms; and the average size of its , relative to the size of the planet itself. Specifically, the larger an average thunderstorm compared to a planet's size, the more likely a polar cyclone is to develop.

O'Neill applied this relationship to Saturn, Jupiter, and Neptune. In the case of Saturn, the planet's atmospheric conditions and storm activity are within the range that would generate a large polar cyclone. In contrast, Jupiter is unlikely to host any polar cyclones, as the ratio of any storm to its overall size would be extremely small. The dimensions of Neptune suggest that polar cyclones may exist there, albeit on a fleeting basis.

The researchers are eager to see whether their predictions, particularly for Jupiter, bear out. Next summer, NASA's Juno spacecraft is scheduled to enter into an orbit around Jupiter, kicking off a one-year mission to map and explore Jupiter's atmosphere.

"If what we know about Jupiter currently is correct, we predict that we won't see these wildly strong cyclones," O'Neill says. "We'll find out next year if our predictions are true."

Explore further: Moist explanation for Saturn's Great White Spots

More information: Polar vortex formation in giant-planet atmospheres due to moist convection, DOI: 10.1038/ngeo2459

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cantdrive85
1 / 5 (3) Jun 15, 2015
What a grand exercise in GIGO. Hundreds of GIGO simulations for hundreds of GIGO days. AGWites should be appalled at the complete waste of resources in this meaningless nonsense.

There is a mechanism which can explain the "hot spots" (on Venus too), the cyclones, the hexagonal feature, as well as the aurora, rings, the rings spokes, and any number of other features that cannot be explained by the standard theory.

http://www.holosc...plained/

Oh, and we shan't forget the "mysterious" and "curious" north polar vortex hot spot was predicted by Mr. Thornhill prior to Cassini's observation.

http://www.holosc...ns-pole/

Vietvet
5 / 5 (4) Jun 15, 2015
@cantdrive

If you're going to offer links to the Electric Universe blog you might as well throw in some others that are just as relevant

.http://www.blogme...strology
http://www.histor...t-aliens
http://bigfootevi...pot.com/
http://www.unicor...rns.html
Captain Stumpy
5 / 5 (3) Jun 16, 2015
@cantdrive

If you're going to offer links to the Electric Universe blog you might as well throw in some others that are just as relevant

.http://www.blogme...strology
@Vietvet
actually, i think your links may actually contain more evidence than even cantdrive's

the closest thing to evidence cd has given is his personal opinion on the meaning and shape of a picture which shows a plasma experiment and his (again) conjectures about how it looks like a(n) [insert galactic or large scale object in the universe]

next he will tell everyone that mallards are proof of birkeland currents and demonstrate that peratt and alfven are correct in their belief that astrophysicists don't understand backgammon and how it relates to 3D chess

@Cantdrive
Linking PSEUDOSCIENCE to support your claims ?
nice try

Now try and find a reputable journal with peer reviewed papers to support your eu PSEUDOSCIENCE
cantdrive85
1 / 5 (3) Jun 16, 2015
And I know I've posted this before, but I could watch it again and again...

https://vimeo.com/40234826

Voyager and Cassini are amazing machines!

And that's not gravity which causes the asteroid to "bounce" off of the rings at :48...
Captain Stumpy
5 / 5 (4) Jun 16, 2015
What a grand...
@cd continued
don't you remember your arguments about this already... in fact, lets be very specific about some of them... starting with the hexagonal Saturn feature you are claiming is formed due to electrical forces

http://phys.org/n...day.html

as we talked about this before (when you couldn't figure out the relationship between "Diocotron Instability" and "Kelvin-Helmholtz instability") in the experiment here:

http://www.planet...471.html

Aguiar and her coauthors argue that it's not the wind speeds that are important per se; it's the gradient in wind speeds
this is something we can see, track and measure - and we know ALL atmosphere's will have multi-speed movement in the gaseous elements clinging to them (and will show various signs we can track/measure)

we see it on Earth
we've replicated the hexagon fairly perfectly W/O your eu BS

JeanTate
5 / 5 (7) Jun 16, 2015
@cantdrive85:
There is a mechanism which can explain the "hot spots" (on Venus too), the cyclones, the hexagonal feature, as well as the aurora, rings, the rings spokes, and any number of other features that cannot be explained by the standard theory
There is? Do you have any primary sources for this? As in, papers published in relevant peer-reviewed journals, which present the mechanism, tie it to established science (such as plasma physics), present data, analyze the data, reach quantitative conclusions, and present the results. Personally, I've never found any, but perhaps you have been more successful than I have.
Oh, and we shan't forget the "mysterious" and "curious" north polar vortex hot spot was predicted by Mr. Thornhill prior to Cassini's observation
Sorry, but that's just non-science. No papers, no ability to independently confirm, no way to independently verify, ... (the method, that is). There are no oracles in science.
JeanTate
5 / 5 (6) Jun 16, 2015
@cantdrive85:
And that's not gravity which causes the asteroid to "bounce" off of the rings at :48...
You're joking, right (even allowing for the fact that it's not an asteroid)?

Apart from the dark 'spokes', all the ring and ring-related phenomena in that video are primarily due to gravity! See, for example, Giuliatti Winter+ (2000) and references/citations therein (Planetary and Space Science, Volume 48, Issue 9, p. 817-827).
cantdrive85
1 / 5 (3) Jun 16, 2015
Oh right, because if there hasn't been a "peer-reviewed" paper written on the subject tied to "established" science it just can't be so. We as humans, we know everything there is to know and it's been published in APJ...
JeanTate
5 / 5 (6) Jun 16, 2015
@cantdrive85:
Oh right, because if there hasn't been a "peer-reviewed" paper written on the subject tied to "established" science it just can't be so
No.

If there are no published papers - which you seem to have confirmed, by the way - one next might ask "Why (not)?"

Is it, perhaps, that the leading proponents do not have the appropriate degrees in science?

Can't be that; Thornhill has a BSc (in physics, I think), and Scott a PhD in a field closely related to plasma physics.

Perhaps, then, this is a very new set of ideas, and the principals haven't yet had time to work on it? Can't be that either ... Thornhill has been working at this for what, nearly 40 years! Likewise Scott.

Perhaps they lack a powerful mentor, someone who can help them (T&C) get papers published? Nah ... for a long time both had Peratt, but their anti-science stances eventually got Peratt to severe ties with them.

Even then, nothing stops T&S writing up their research like a paper ...
cantdrive85
1 / 5 (2) Jun 16, 2015
If there are no published papers - which you seem to have confirmed, by the way - one next might ask "Why (not)?"


Well, if you choose willful ignorance over a simple web search, then I guess you'd think so wouldn't you.

Here are several IEEE papers;
http://ieeexplore...rch=true

Dr. Scott's synopsis of his book and papers;
http://electric-c...xOLD.htm

Perhaps, then, this is a very new set of ideas, and the principals haven't yet had time to work on it?


It's nice to see you are a master at disinformation similar to Timmy Thompson and Tom Bridgeman as well as some of your fellow posters.

You're right it's not a new set of ideas, Birkeland started developing them over a hundred years ago using experiment. Oddly mainstream theorists ignored them for 60+ years until in situ measurements showed him to be correct. Couldn't be willful ignorance could it?
cantdrive85
1 / 5 (1) Jun 16, 2015
Thornhill has been working at this for what, nearly 40 years! Likewise Scott.


You got a "primary source" for that? If one read a Velikovsky book 40 years ago that mean's you've been "working on it for 40 years"? Neither started publishing there ideas until the late "90's- early '00's, I guess if you multiply by 4 you'd be close. BTW, don't you agree that if it is a paradigm shifting theory as they suggest it should take some time when there are only a handful of people working on it?

Even then, nothing stops T&S writing up their research like a paper ...


Nonsensical statement based upon willful ignorance, you got anymore?
cantdrive85
1 / 5 (1) Jun 16, 2015
Damn, Vietbabykiller! Why don't you get a job greeting people at Walmart instaed of stalking/trolling me 24/7?
Vietvet
5 / 5 (2) Jun 16, 2015
Damn, Vietbabykiller! Why don't you get a job greeting people at Walmart instaed of stalking/trolling me 24/7?


@cantdrive

Don't flatter yourself. I read a high percentage of the PO articles everyday. When I come across pseudoscience I respond with a down vote and/or refuting links/comments.

JeanTate
5 / 5 (1) Jun 16, 2015
@cantdrive85:
[me]If there are no published papers - which you seem to have confirmed, by the way - one next might ask "Why (not)?"
[you]Well, if you choose willful ignorance over a simple web search, then I guess you'd think so wouldn't you.
My bad. I thought the context was perfectly clear (re "There is a mechanism which can explain the "hot spots"": "Do you have any primary sources for this? As in, papers published in relevant peer-reviewed journals, which present the mechanism, tie it to established science (such as plasma physics), present data, analyze the data, reach quantitative conclusions, and present the results."), but I guess not. I'll try harder in future.

Anyway, I looked at your two sources, and didn't find anything to do with Saturn, its hot spots, hexagonal pattern, etc. So I guess it's true; neither T nor S published any papers on this topic.
JeanTate
5 / 5 (2) Jun 16, 2015
@cantdrive85:
You're right it's not a new set of ideas, Birkeland started developing them over a hundred years ago using experiment.
Which, as your lists make clear, neither Thornhill nor Scott have done any work on (of the published papers kind) as these relate to Saturn, its hexagonal feature, as well as the aurora, rings, the rings spokes, and any number of other features. You could have been upfront about this from the beginning.
You got a "primary source" for that?
It's something I read, IIRC, on one or other of the T or S sites. However, a quick search turned up this:
Thornhill was invited to attend the first international Velikovskian conference at McMaster University in Hamilton, Ontario, in 1974, on the subject of The Recent History of the Solar System.
That's ~41 years, pretty close, eh? (source: www.velikovsky.in...ornhill)
JeanTate
5 / 5 (2) Jun 16, 2015
@cantdrive85:
BTW, don't you agree that if it is a paradigm shifting theory as they suggest it should take some time when there are only a handful of people working on it?
No. As you yourself pointed out, there's a vast literature on plasma physics, and the works of Alfven and Birkeland (to take just two of your fave scientists) freely available.

But let's not get distracted; this is your claim:
There is a mechanism which can explain the "hot spots" (on Venus too), the cyclones, the hexagonal feature, as well as the aurora, rings, the rings spokes, and any number of other features that cannot be explained by the standard theory.
I asked you to provide *scientific* evidence for your claim, and you have not been able to.
[me]Even then, nothing stops T&S writing up their research like a paper ...
[you]Nonsensical statement based upon willful ignorance, you got anymore?
Au contraire. If T&S want to do science, they need to publish papers. Period.
JeanTate
5 / 5 (2) Jun 16, 2015
@cantdrive85:
It's nice to see you are a master at disinformation similar to Timmy Thompson and Tom Bridgeman as well as some of your fellow posters.
That got you my downvote.

So far, on this topic, you have been unable to back up your claims concerning Saturn, its hexagonal feature, etc. Back up as in provide primary sources which present the mechanism, tie it to established science (such as plasma physics), present data (i.e. things like observations of Saturn, its hexagonal feature, etc), analyze the data, reach quantitative conclusions, and present the results.
cantdrive85
1 / 5 (1) Jun 16, 2015
And that's not gravity which causes the asteroid to "bounce" off of the rings at :48...

You're joking, right (even allowing for the fact that it's not an asteroid)?


Excuse me, moonlet, space rock, unknown object bouncing off of "gravitated" space dust. So now gravity has repellent space stuff properties? I think it's you who is joking.

BTW, No answer to my question as to why the mainstream ignored experimental based science in favor of purely theoretical mumbo jumbo for 60+ years?
JeanTate
5 / 5 (2) Jun 16, 2015
@cabntdrive85:
Excuse me, moonlet, space rock, unknown object bouncing off of "gravitated" space dust. So now gravity has repellent space stuff properties?
It doesn't. Cassini, which 'took the pictures', is moving; so is the moonlet, and the ring (F ring?). The orbits of all three are close to, but not exactly, Keplerian. Did you check out Giuliatti Winter+ (2000)?
BTW, No answer to my question as to why the mainstream ignored experimental based science in favor of purely theoretical mumbo jumbo for 60+ years?
Correct. I have no intention of responding to such patent nonsense. Especially as my primary interest, here and now, is investigating your claims that, wrt Saturn:
There is a mechanism which can explain the "hot spots" (on Venus too), the cyclones, the hexagonal feature, as well as the aurora, rings, the rings spokes, and any number of other features
So far, you have presented zero scientifically valid primary sources on this.

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