Weird Atmospherics — Curious Clouds Of Jupiter And Earth

Jupiter’s swirling clouds are made mostly of ammonia ice with traces of sulfur, methane and other compounds. Powerful jet streams in the planet’s upper atmosphere moving at around 400 mph stretch and twist the clouds as well as help to create and sustain eddy-like storms like the one at upper left. NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt /Seán Doran

Hands down Jupiter’s got the most the bizarre clouds in the solar system. All those swirls, whirls and vortices look like so much cream in a cup of coffee. If you’d asked Van Gogh to paint Jupiter sight unseen, I’m sure it would bear a remarkable resemblance to the real thing. Clouds form on Jupiter the same way they do on Earth only it’s much colder there because the planet is five times farther from the sun.

Another photo taken by NASA’s orbiting Juno spacecraft of Jupiter showing colorful bands of clouds including one shaped like a dolphin. Can you spot it? NASA/Brian Swift/ Seán Doran

In Jupiter’s upper atmosphere, crystals of ammonia ice condense to form the cloud deck we see through our telescopes. Deeper down, clouds combining ammonia and hydrogen sulfide (a smelly, dangerous gas) dominate, while several hundred miles below that, where temperatures are warmer, clouds are composed of familiar water vapor.

These chaotic clouds are part of a squall line associated with the arrival of a cold front and thunderstorms that blew over my neighborhood two weeks ago. Strong winds are associated with the clouds. Bob King
Another view of the approaching squall line. Bob King

Jupiter rightfully gets a lot of attention for its clouds, and the latest Juno photos reveal them in incredible detail, each image more amazing than the next. But I’d like to also through in a vote for Earth, a planet with lots of weather and one where you can see amazing clouds without the need for a telescope — or a clear night!

If you regularly look up, there’s a cloud feast up there. Some are rare but many common forms can take on a special beauty depending on time of days, upper atmospheric winds and what a particular cloud might be doing right now over your house or apartment. Variations in textures and forms can sometimes last just minutes, so take the time to admire nature’s evanescence.

A rare triple halo appeared just this Friday (June 21) over northern Minnesota. Besides the outer 22° halo two interior halos with diameters of 18° and 9° were seen. These so-called “odd radius” halos are formed by pyramid-shaped ice crystals. Bob King

If a thunderstorm is forecast be on the alert for the Jupiter-like whorls of squall line clouds. Close examination of squall lines will often reveal rotation in the clouds from high winds.

We’ve talked about halos here many times. They’re formed by light refracted by pencil-shaped, six-sided ice crystals in high clouds. The most common halos have a radius — the distance from the sun to the edge — of 22° or two side-by-side fists held against the sky. Rarely, halos of different diameter called “odd radius” halos can appear when light is refracted by pyramidal crystals. This past Friday afternoon the normal 22° halo looked unusually soft and bloated. At the same time I noticed fainter inner arcs that I could trace partway around the sun — baby halos with radii of 18° and 9°!

Cirrocumulus clouds edge every closer to the sun yesterday. Bob King

Then on Saturday (June 22), while stopped at a gas station, a raft of cirrocumulus clouds shaped like a bird of prey approached the sun from the west. When I pointed out the cloud to another person standing by the first words out of his mouth were “the UFOs are coming.” Cirrocumulus are a high altitude version of the familiar cauliflower-shaped summertime cumulus. They form from 3 to 7 miles high and look like narrow, wavy bands made of tiny clouds puffs. Sometimes the higher ones can look smooth at first and then develop into narrow, gill-like rows right before your eyes.

A wide view of the cirrocumulus sheet that blew by Saturday. Notice the transition from smooth to puffs midway up. The sun is out of the frame at upper left. Bob King

Cirrocumulus are transitional clouds in a weather front pattern and generally don’t last long. These hung around for about 45 minutes before spreading and evaporating away. Ah, life is too brief.

Lenticular clouds are often saucer-shaped and form when fast moving air blows over mountains or hills, creating waves in the atmosphere similar to those that form when you toss a pebble in a pond. These showed up where I live last month. Bob King

I have many favorites would argue that Earth has cloud skills to rival the solar system’s biggest planet. That said, here are a few other spectacular types you might see at any time. If you’d like to learn more about clouds, here’s a simple guide. To learn more I highly recommend the World Meteorological Association’s International Cloud Atlas.  They also have an extensive photo gallery useful for identifying clouds you’re not sure of.

I usually finish with a “clear skies!” but this time I wish you clouds 🙂

James Schaff of Duluth photographed these rare Kelvin-Helmholtz wave clouds over the Wisconsin shore of Lake Superior. They form when two layers of air are moving at different speeds, a phenomenon called shear. Air streaming above is moving faster than air at the base of the clouds, causing the tops to topple over. James Schaff
Billows of mammatus (“mammary clouds”) typically hang from the base of a cumulonimbus thundercloud and are associated with strong, downward-blowing winds. Eat your heart out, Jupiter. Bob King

1 Response

  1. kevan hubbard

    I must admit that the only clouds on Earth I take much interest in are noccullient and nacrous clouds although we shouldn’t knock high Cirrus as I’ve seen wonderful halos around the full moon through cirrus.i suppose Cirrus are the last of the normal clouds before we move on to such exotic fare as noccullient and nacrous clouds these are so exotic that they’re not even in most cloud guides.nacrous so exotic I don’t think that I’ve ever seen them although I suppose that I could have done before I was interested in such things?I was up in narvik, Norway (if I recall 69 North)so years back but in April but I don’t recall what the weather was like,not brutally cold if memory serves me correctly about 0c..

Comments are closed.