Did strange clouds foretell China quake?

By Phil Plait | May 22, 2008 12:58 pm

In China, just minutes before the enormous 7.8 magnitude earthquake that killed so many people, beautiful colors were seen in the sky.

Did this phenomenon foretell the coming of the earthquake?

No, of course not. I knew right away what these were: high altitude icy clouds. Sunlight passing through them gets diffracted, broken up into colors like a rainbow. Under normal circumstances you get a complete halo around the Sun, which can be heart-stoppingly beautiful. Different kinds of clouds produce different effects (fire clouds are particularly cool).

In the case of the colors seen in China before the earthquake, the clouds were patchy, which is why you don’t see a continuous stream of color horizontally. Instead, spots of local color are seen. The order of the colors is clearly ROYGBIV, the same as in a rainbow or circumhorizon arc. Not only that, but the videos were taken in mid-afternoon, around 2:00 p.m. local time, and the Sun would have been high in the sky, just where it should be to get this effect.

I see things like this all the time, because I do something a lot of folks don’t do: I look up. Seriously, it’s that simple. When you do that, you get to see halos, sundogs, and arcs quite often. It’s usually in the winter, but it doesn’t have to be. You just need high, icy clouds.

So what we have here in China is just a normal, if not exactly everyday, atmospheric effect. If people just looked up more, they would have seen this for what it is, a pretty sight in the sky that has nothing at all to do with the earthquake that would change their lives so drastically less than an hour later.

Remember: post hoc ergo propter hoc — after this, therefore because of this — is called a logical fallacy for a reason.

Tip o’ the tin foil beanie to Michell Astudillo, via Fark.


Comments (39)

  1. SteveT

    I saw rainbow clouds like that for the first time a couple of weeks ago here in Minnesota. They were beautiful! Much more impressive than the usual sun dogs and solar halos we see around here.

    It’s nice to know that this wasn’t a portent of massive death and destruction. I’m SO relieved! 😉

  2. wright

    I wondered about the connection too. But then looking at the video, it was clear those clouds were like many I’ve seen myself, and I don’t remember any earthquakes associated with them. And I’m a 4th-generation Californian.

    People want answers and are always looking for patterns, especially at times of tragedy and suffering. But another thing is, photography (still and motion) has been fairly widespread for over a century now. If there really was a connection between atmospheric phenomena and incipient earthquakes, surely there would be evidence for it.

    Unfortunately there doesn’t seem to be. It would have been invaluable to have had a half-hour’s warning of that quake.

  3. Kevin

    I don’t know. Last week we had those clouds, and a short time later we had an earthquake.

    well… maybe. Or it was the demolition of a building nearby. :)

  4. Michelle

    I see them pretty often too. I think I pretty much saw one every sunny day of winter this year.

    I HOPE some people are not truly believing this nonsense

  5. Itzac

    I was just reading the Fark thread from the footnote. There’s some pretty bizarre explanations there.

    My favorite had to be that low frequency vibrations around metal deposits created a magnetic field, polarizing water molecules so they would create the prism effect. They also repeat the myth that very few animals die in tsunamis.

    If only there was some way to store information in a way that it could be retrieved from anywhere in the world, maybe through some kind of network. And the system could be distributed across the globe so that single failures wouldn’t break the whole thing. Such an Interconnected Network could revolutionize the way people get media and information. If only…

  6. Kristin

    Well, I’m glad to see that someone updated the Wikipedia article on this phenomenon (about the China incident) since last time I looked, because I was going to write here and tell someone to update it. Speaking of
    http://en.wikipedia.org/wiki/Earthquake_light – what’s up with that really? I don’t trust Wikipedia on this. Is it a phenomenon or just woo? Someone smart please clarify. I’m curious here.

  7. “While EQL sightings are often given more exotic labels, they are a recognized geophysical phenomenon that may one day contribute to the possibility of forecasting earthquakes in the few locations where they occur.”

    This is from the USGS website. So, while THESE clouds are high altitude icy clouds, earthquake lights are real. We may not understand the mechanism behind them, but they do exist.

  8. Michelle

    Oh man. Look at the comments on the video itself. In fact, look at that one:

    “djviranga (25 minutes ago)

    the clouds are infact a warning of earthquakes. they are called earthquake facts. 30 minutes before the earthquake hit, some officials were denying that there would be an earthquake anytime soon. they were wrong and innocent lives payed for their mistakes. ”

    I wonder how much in depth research that dude/ette did.

  9. I see things like this all the time, because I do something a lot of folks don’t do: I look up.

    It’s also a good defense against alien critters lurking in your home, place of business, or whatever. When the character can’t see the alien, it is always on the ceiling. It’s a fundamental rule of existence. I think it even appears in Leviticus. 😉

  10. I just wish I had a camera available more often.

    About 10 years ago (long before cell-phone cameras were available), I was driving home and saw an amazing rainbow. It was probably the strongest I’ve ever seen, to the point that a secondary bow was as strong as the primary bows I usually see, and there was even a tertiary bow visible.

    On the other hand, I do point out rainbows to my kids, and they’re always delighted to see one. (They even point them out to me sometimes.)

    “I look up” applies to my family quite nicely, TYVM.

    And I’m glad to see your post links to the Atmospheric Optics site. I keep a tab open to their “what’s new” page to check every few days.

  11. aporeticus

    It’s all delayed effects from TU24. 😉

  12. Hey, how come they’re speaking Chinese in that video from China?

  13. Thanny

    I think BA is flat out wrong on this one. There are several videos of earthquake lights (a genuine phenomenon) before this quake, and not all of them line up with distant clouds.

  14. Michelle

    @thanny: I have yet to hear real proofs of that.

    The BA is right. These are Circumhorizontal Arcs.

  15. Thanny, nope, I’m right. Earthquake lights may be real, but if so, the video I showed isn’t part of them. Those are definitely diffraction effects in clouds.

  16. The science behind these phenomena and a whole lot more can be found at http://www.atoptics.co.uk You can spend hours looking through the amazing phenomena and understanding the incredible things which are regularly above us if we only take the time to look!

  17. Chip

    The clouds also look a bit like diffuse sky writing. Sky writing that has spread and smeared after a half hour due to winds. Its not, but I wonder if they have sky writing in China? (Chinese writing being so elaborate, it seems it might be harder for a pilot to do than flying to shape Western letters and words as well as some Japanese characters.) But I digress –

    When I lived in Arizona, we’d see “sun dogs” a daytime phenomenon which sometimes looked like small bright spots in thin high clouds with a dash of glowing rainbow colors. Really cool to see. Sometimes it seems like they were mirroring the sun on either side.

    Another wonderful sight is a complete ring around the high full moon at night. It can look like a giant eye in the sky.

    The sudden disappearance of birds, horses acting nervous, cats hiding, or muddy water inexplicably bubbling up trough manhole covers, which happened before several San Francisco earthquakes, might be a more serious portent of an approaching earthquake. John Muir noted that hours before Yosemite earthquakes, Native Americans would leave or seek open ground. They were watching the animals. All anecdotal observations I know, but perhaps worthy of study.

  18. Thanny

    I had another look at the other videos, and I have to agree now. What looked like a shot directly overhead (which would make the angles all wrong for cloud prisms) was actually just a high zoom level of very high clouds.

    It also seems that actual earthquake lights don’t look quite like that.

  19. James

    Speaking of strange weather, tornadoes struck not more then an hour away from you. Is everything ok there?

  20. Openmineded

    In the conspiracy world, there is a theory floating around that the USA is in a “weather war” with China..

    We are using our “HAARP” up in Alaska to cause catastrophes in China… and china is using their version of the HAARP, and has caused the several midwest earthquakes, and maybe even today’s colorado tornado (some of the earthquakes aren’t reported on the USGS site for some reason, therein lies the conspiracy)…

    Also a tornado hit the earthquake zone shortly after the earthquake…

  21. tom.a

    Here’s a page on Earthquake Lights with a couple video links.

  22. James


    Wow.. Even if that were true, wouldn’t they make a powerful tornado strike a large city, instead of the regular tornadoes the Midwest gets annually?.. I hate the conspiracy world, though its fun to debunk.

  23. I saw (and photographed) a fragment of a circumhorizon arc a few weeks ago in California, intersecting with a light, feathery-looking cloud.

    I actually caught a sundog on my way home from work tonight, but didn’t get a decent photo.

    FWIW, no quake followed either.

  24. Geomancer


    Although I don’t browse the USGS site daily (earthquakes aren’t my cup of rocks), I haven’t seen any quakes reported on another news source that didn’t show up on USGS…could you provide sources? I don’t generally buy into the conspiracy theory, and the USGS has been solid as far as I’ve seen (e.g we had a 4.0 about 200 miles away at 1 AM a couple years ago, and it was posted on USGS within minutes – long before CNN.com caught it). Obviously, nobody’s perfect, but the few quakes in my region during the last few years have been posted promptly.

  25. Jim Hammond

    I thought I had seen a good explanation somewhere before! Aha! Here it is:

    BA: You may notice that in this earlier post you called this a “refraction” phenomenon, not something caused by “diffraction”. A minor, but important difference. We have a nice picture of this phenomenon seen in Bend, Oregon a couple of years ago.

    I’m sure people think it strange when I stick my fist up and stare at the sun to look for halos or sun dogs and the like. When I mention the halo or whatever they generally look up but don’t use their fist to block the sun. Ow! that hurts!

    As Jack Horkheimer used to say (maybe he still does), “Keep looking up!”

  26. Shoeshine Boy

    Mostly unrelated… but late yesterday afternoon I saw a perfect double rainbow. The sky above my home had some patchy clouds, with one giant raincloud approaching. It passed directly over my house from west to east creating a “sun shower.” Figuring this was a perfect setup for a rainbow, I ran to the front door (faces east) and was treated to two of the most perfect rainbows I have ever seen. They both passed infront of clouds and “clear” sky and the colors were very vivid. If only I’d remembered where I put my camera.

  27. Charles

    “Earthquake lights may be real”


    Even a skeptic like you has to admit that there is valid scientific evidence of the EQL phenomenon. Friedemann Freund’s p-hole experimentation pretty much confirmed the validity of them.

  28. Celtic_Evolution

    @ Charles

    Phil isn’t arguing against the existence of “earthquake lights”, in general. He’s arguing that what’s in this video isn’t an example of them. That’s all.

  29. Charles

    Celtic – fair enough. Phil is more than fair and I must have misunderstood him.

    BTW, Phil, I sent your link to my Dad, who was part of the Apollo mission support folks at KSC back in the day. He was very impressed and very happy to see that someone out in the ‘Net is solidly defending the real work that he and the tens of thousands of others did.

  30. Thanks for clearing this up Phil. This was on CNN Headline News a couple days ago and they said there was no known explanation. This from a meteorologist!.

    It’s always disappointing to see the media spreading more “woo”.

  31. SpikeNut

    Sundogs and rainbows in clouds may not portend an earthquake, but it must be that rainbows in clouds shaped like snails (like the one on the left early on in the video) do!


  32. Eric TF Bat

    I think “No, of course not” is a bit harsh. If you’ve never seen or heard of this whole rainbow-cloud phenomenon, then [unexpected event] + [short delay] + [other unexpected event] is a good first step toward making a theory. Consider: you hear a gunshot; someone falls over dead. Even if you’ve never heard gunshots before and don’t know what they are, it’s a reasonable hypothesis that the two events are related causally as well as temporally.

    Now, going ahead and saying they MUST be related, without checking routinely for other explanations, THAT’s bad logic. But “no, of course not” implies that the original guess was wrong too, and I think you’re doing the observers a disservice there.

  33. Richard H.

    I showed a sundog pair to a friend of mine. She thought it was the coolest thing ever. I pointed out a full rainbow. She thought that was cool too. I showed her a sun halo. Yes, it was cool, too.

    I look up to the sky plenty of times. But I see nature there, as it is.

    Ever notice the rainbow’s mirror image? How about the fainter sundogs?

    Heck, I’ve even see green clouds. Green clouds! And I’m from central California.

  34. Jim Hammond

    Oops! I should have checked the link in Phil’s original post. The “fire cloud” link is to the blog entry I linked above.

    I also should have made it clear I was trying to say that I think “refraction” is the cause of most of the phenomena discussed here, not “diffraction”. Diffraction causes effects called “coronas” and some other atmospheric optical effects but refraction/reflection in hexagonal ice crystals is responsible for sun dogs and halos and the circumhorizontal arc. Rainbows are caused by refraction/reflection in spherical drops. There are also interference effects apparently observed in atmospheric optical effects such as iridescent clouds.

    I think the clouds observed in China were, in fact, a circumhorizon arc.

    Phil: were you saying this too?

  35. I’ve actually seen clouds exactly like that here in New Brunswick, Canada earlier this year.

    Looked like those Rocketship popsicles with the pink, white and blue layers. Spectacular, but didn’t portend anything unusual as far as weather or geological events.

  36. It’s the HAARP. Good luck to the Chinese.

  37. Rudy H.

    Can someone please explain how rainbow phenomena was seen in China prior to the quake and also Augusta, Maine USA and possible other locations all on the same day May 12, and around the same time period? I have pics.


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