Investigating Mysteries of the Deep, Dark Night

Conspiracy theorists will tell you that conspiracies exist everywhere; that they’re part of daily life; and that most people are ignorant of all the attempts by various governments around the world to covertly control every facet of your life. Only they know the truth. But, that’s just what they want you to believe! Conspiracy theorists are simply manipulating you in order to control you and create a New World Order! Wake up!

Full disclosure: I am subsidized by the U.S. government to inform people of the capabilities and uses of the satellite instrument called VIIRS and today I’ll show you how that satellite instrument can help separate fact from fiction when it comes to the latest conspiracy theory. (Of course, working for the government means I could be part of the conspiracy!  Mwa ha ha!)

During the last week of August 2014, I was sent this link to a story from a pilot/photographer who captured “the creepiest thing so far” in his long flying career. I’ll quote his initial post again in its entirety here (for those of you too lazy to click on the links):

Last night [24 August 2014] over the Pacific Ocean, somewhere South of the Russian peninsula Kamchatka I experienced the creepiest thing so far in my flying career. After about 5 hours in flight we left Japan long time behind us and were cruising at a comfortable 34.000ft with about 4,5 hours to go towards Alaska.
We heard via the radio about earthquakes in Iceland, Chile and San Francisco, and since there were a few volcanos on our route that might or might not be going off during our flight, we double checked with dispatch if there was any new activity on our route after we departed from Hongkong.

Then, very far in the distance ahead of us, just over the horizon an intense lightflash shot up from the ground. It looked like a lightning bolt, but way more intense and directed vertically up in the air. I have never seen anything like this, and there were no flashes before or after this single explosion of light.

Since there were no thunderstorms on our route or weather-radar, we kept a close lookout for possible storms that might be hiding from our radar and might cause some problems later on.

I decided to try and take some pictures of the night sky and the strange green glow that was all over the Northern Hemisphere. I think it was sort of a Northern Lights but it was much more dispersed, never seen anything like this before either. About 20 minutes later in flight I noticed a deep red/orange glow appearing ahead of us, and this was a bit strange since there was supposed to be nothing but endless ocean below us for hundreds of miles around us. A distant city or group of typical Asian squid-fishing-boats would not make sense in this area, apart from the fact that the lights we saw were much larger in size and glowed red/orange, instead of the normal yellow and white that cities or ships would produce.

The closer we got, the more intense the glow became, illuminating the clouds and sky below us in a scary orange glow. In a part of the world where there was supposed to be nothing but water.

The only cause of this red glow that we could think of, was the explosion of a huge volcano just underneath the surface of the ocean, about 30 minutes before we overflew that exact position.

Since the nearest possible airport was at least 2 hours flying away, and the idea of flying into a highly dangerous and invisible ash-plume in the middle of the night over the vast Pacific Ocean we felt not exactly happy. Fortunately we did not encounter anything like this, but together with the very creepy unexplainable deep red/orange glow from the ocean’s surface, we felt everything but comfortable. There was also no other traffic near our position or on the same routing to confirm anything of what we saw or confirm any type of ash clouds encountered.

We reported our observations to Air Traffic Control and an investigation into what happened in this remote region of the ocean is now started.

If you go back and click on the link, you’ll see he posted several pictures of the mysterious red lights along with more detailed information about where and when this occurred. To save you some time, here is a representative picture (taken at 11:21 UTC 24 August 2014). And here is the location of the aircraft when they saw the lights.

There are three parts to this story: 1) the bright flash of light that looked like lightning coming up from the surface; 2) the aurora-like features in the sky; and 3) the red and orange lights from the clouds below that appeared to be larger than ordinary ship lights.

Since the story was first posted, people from all over commented on what they thought the lights were and the pilot has been updating his webpage to cover the most common and/or most likely explanations. The media picked up the story and used it to claim the world was coming to an end. Existing theories range from UFOs (unidentified flying objects) and UUSOs (unidentified under-surface objects) operated by space aliens to covert military operations to spontaneously-combusting methane bubbling out of the ocean to “earthquake lights“. The pilot himself initially thought it was an underwater volcanic eruption.

So, can VIIRS shed light on what was going on? Yes – at least, on #2 and #3. VIIRS passed over the area in question at 15:35 UTC on 24 August, which is about 4 hours after the pilot took his pictures. This means VIIRS can’t say anything about the lightning-like flash that was observed. So #1 is unexplained.

As for #2 – the aurora-like features in the sky – those are simply airglow waves. We’ve discussed airglow and airglow waves before here and here.

Now, onto #3 where VIIRS is most informative: the mysterious surface lights. I mentioned the VIIRS overpass at 15:35 UTC on 24 August. Here’s what the Day/Night Band (DNB) saw:

VIIRS Day/Night Band image from 15:35 UTC 24 August 2014.

VIIRS Day/Night Band image from 15:35 UTC 24 August 2014.

Look at 47.5°N latitude and 159°E longitude. (You can click on the image, then on the “4329 x 2342” link below the banner to see the full resolution image.) Those are the lights the pilot saw! (Note also that this night was near new moon, so any illumination of the clouds in that area comes from airglow. Light in the northeast corner of the image is twilight from the approaching sunrise.)

Now, VIIRS also has bands in the short-, mid- and long-wave infrared (IR). Surely, they must have seen the heat signature put out by a volcanic eruption, right? Not necessarily. The pilot’s photographs clearly show the lights shining through a layer of clouds, and it doesn’t take much cloud cover to obscure heat signatures at these wavelengths. But, for completeness, here are the observed brightness temperatures at 3.7 µm (channel M-12) and 10.7 µm (channel M-15):

VIIRS M-12 image from 15:35 UTC 24 August 2014

VIIRS M-12 image from 15:35 UTC 24 August 2014

VIIRS M-15 image from 15:35 UTC 24 August 2014

VIIRS M-15 image from 15:35 UTC 24 August 2014

I don’t see any hotspots in either of those images near the location of the lights. But, as I said, this doesn’t disprove the presence of flaming methane or volcanic activity because of possible obscuration by clouds. (Note that the clouds are easier to see in the DNB image than either of the IR images because there is no thermal contrast between the clouds and the open ocean for the IR images to take advantage of. There is, however, reflection of airglow light available to provide contrast in the DNB.)

What about the night before? The night after? Were the lights still there?

Here’s the DNB image from 15:54 UTC 23 August 2014 (aka the night before):

VIIRS DNB image from 15:54 UTC 23 August 2014

VIIRS DNB image from 15:54 UTC 23 August 2014

The light is there in pretty much the same place, although it looks like one big circle instead of a number of smaller lights. What is going on? Once again, it’s clouds. This time, the longwave IR shows we have optically thicker and/or an additional layer of high clouds over the lights:

VIIRS M-15 image from 15:54 UTC 23 August 2014

VIIRS M-15 image from 15:54 UTC 23 August 2014

Optically thicker clouds scatter and diffuse the light more, and what you are seeing in the DNB image is the area of clouds surrounding the light source that scatter the light to the satellite. See how clouds scatter the city lights of the U.S. Midwest in this comparison between the DNB and M-15 from 07:42 UTC 2 September 2014:

(You may have to refresh the page if this before/after image trick doesn’t work.)

It’s not that Chicago, Illinois and Gary, Indiana extend that far out into Lake Michigan or that the map is not plotting correctly. It’s that the optically thicker clouds over the southern end of the lake scatter more of the light back to the satellite (and over a larger area than the lights themselves), making it appear that the light is coming from over the lake.

Similarly, scattering in the clouds makes the individual “mystery lights” over the Pacific Ocean appear to be one large area of light, instead of a number of smaller lights.

How do the lights look on 25 August 2014 (aka the night after)? Here’s the DNB image:

VIIRS DNB image from 15:18 UTC 25 August 2014

VIIRS DNB image from 15:18 UTC 25 August 2014

Did you notice that? The lights aren’t in the same place as before. They moved. In fact, I tracked these lights in the DNB for two weeks. And I got this result:

Do volcanoes move around from day to day? I think we can safely say the pilot was not observing a volcanic eruption.

Now, I don’t know much about spontaneously combusting methane bubbles in the ocean, but I doubt they are this frequent. The pilot found another pilot’s report of methane burning over the ocean from 9 April 1984 (which also occurred during a flight from Japan to Alaska) but, that was during the day and it was the resulting cloud that was spotted, not the actual flames. There is no evidence of clouds being produced by these lights over this two week period. There also isn’t much evidence from seismic activity over this period to justify earthquake lights.

Another theory put forth was meteorites but, again, it seems highly improbable that VIIRS would be capturing this many meteorites hitting this localized area of the Pacific Ocean every night for two weeks. Plus, they would have to be pretty large meteors to appear as large as these lights.

Unless you believe in UFOs (or UUSOs), that leaves only one question: why were the pilots of this flight so quick to dismiss ships? The DNB has seen ships on the ocean before, and they look a lot like this. (You can find examples of individual boats observed by the DNB here and an example of larger squid boat operations here.)

It is true that most squid boats use white or greenish light and the pictures clearly show red and orange lights coming up through the clouds. But military ships are known to use red lights at night, at least, according to Yahoo! Answers.

If it looks like a fleet of ships and moves like a fleet of ships, I’m guessing it’s a fleet of ships. Unless, of course, it’s a gam of sharks with freakin’ laser beams attached to their heads.


Severe Weather in the Mesosphere

So far (*knock on wood*), it’s been a pretty quiet year for severe weather. If you only count tornadoes, there have been 81 tornado reports from 1 January to 4 April this year. (11 of those have come just this week.) This is a lot fewer than the previous three year average of 192 tornadoes by the end of March. For that, you can thank the dreaded, terrifying “Polar Vortex” you’ve heard so much about over the winter. Tornadoes don’t like to come out when it’s cold everywhere. (Although, there was a notable exception on 31 March 2014, when a tornado hit a farm in Minnesota when the area was under a blizzard warning.)

I just said that there have been 11 tornado reports this week. Eight of those came in the past 24 hours. At the southern end of the line that brought the tornadoes to Illinois, Missouri and Texas, the severe weather included golf ball-size hail and this:


That report came from the National Weather Service in Corpus Christi, TX and it was caused by non-tornadic straight-line winds in Orange Grove. Winds capable of ripping a shed out of the ground, combined with golf ball-sized hail – that’s one recipe for broken windows. And it’s not a pleasant way to be awakened at 4:30 in the morning.

A couple of hours earlier, VIIRS caught this severe storm as it was rapidly growing. Here’s what the storm looked like in the high-resolution infrared channel (I-5, 11.45 µm):

VIIRS high-resolution IR image (channel I-5), taken at 08:13 UTC 4 April 2013.

VIIRS high-resolution IR image (channel I-5), taken at 08:13 UTC 4 April 2013.

Make sure you click on the image, then on the “2999×2985” link below the banner to see the full resolution image, which, for some reason, is the only version where the colors display correctly.

The storm that hit Orange Grove is the southern-most storm, with what looks like a letter “C” imprinted on the top. (That kind of feature typically looks more like a “V” and makes this an “Enhanced-V” storm, which you can learn more about here. Enhanced-V storms are noted for their tendency to produce severe weather.) For those of you keeping score at home, the coldest pixel in this storm is 184.7 K (-88.5 °C).

Compare the image above with the Day/Night Band image below (from the same time):

VIIRS Day/Night Band image, taken at 18:13 UTC 4 April 2014

VIIRS Day/Night Band image, taken at 08:13 UTC 4 April 2014

There are a few interesting features in this image. For one, there’s a lot of lightning over Louisiana, Arkansas and Mississippi. (Look for the rectangular streaks.) There’s even some lighting visible where our “Enhanced-V” is. Two, it takes a lot of cloudiness to actually obscure city lights: only the thickest storm clouds appear to be capable of blocking out light from the surface. Three: there are a lot of boats out in the Gulf of Mexico at 3 o’clock in the morning (and a few oil rigs as well). And four: notice what appear to be concentric rings circling the location where our severe storm is with its enhanced-V.

In this image, there is no moonlight (we’re before first quarter, so the moon isn’t up when VIIRS passes over at night). The light we’re seeing in those ripples is caused by “airglow”, which we’ve seen before. And the ripples themselves may be similar to what is called a “mesospheric bore.” If you don’t want to get too technical, a mesospheric bore is when this happens in the mesosphere. They are related to – but not exactly analogous to – undular bores, which you can read more about here.

Unlike the situation described for the undular bore in that last link, the waves here are caused by our severe storm. To put it simply, we have convection that has formed in unstable air in the troposphere. This convection rises until it hits the tropopause, above which the air is stable. This puts a halt to the rising motion of the convection but, some of the air has enough momentum to make it in to the stratosphere. This is called the “overshooting top“, and is where our -88°C pixels are located. (Look for the pinkish pixels in the middle of the “C” in the full-resolution infrared image.) The force of this overshooting top creates waves in the stable layer of air above (the stratosphere) that propagate all the way up into the mesosphere. The mesosphere is where airglow takes place, and these waves impact the optical path length through the layer where light is emitted. This of course, impacts the amount of light we see. The end result: a group of concentric rings of airglow light surrounding our storm.

You could make the argument that the waves we see in the Day/Night Band image are not an example of a bore. Bores tend to be more linear and propagate in one direction. These waves are circular and appear to propagate in all directions out from a central point. It may be better to describe them as “internal buoyancy waves“, which are similar to what happens when you drop a pebble into a pond. Only, in this case the pebble is a parcel of air traveling upwards, and the surface of the water is a stable layer of air. Compare the pebble drop scenario with this video of a bore traveling upstream in a river to see the difference.

In fact, if you look closer at the Day/Night Band image, in the lower-right corner (over the Gulf of Mexico) there is another group of more linear waves and ripples in the airglow that may actually be from a bore. It’s hard to say for sure, though, without additional information such as temperature, local air density, pressure and wind speeds way up in that part of the mesosphere.

By the way, you can see mesospheric bores and other waves in the airglow if you have sensitive-enough camera, like the one that took this image:

Photograph of a mesospheric bore. Image courtesy T. Ashcraft and W. Lyons (WeatherVideoHD.TV)

Photograph of a mesospheric bore. Image courtesy T. Ashcraft and W. Lyons (WeatherVideoHD.TV)

And, if you’re interested, the Arecibo Observatory has a radar and optical equipment set up to look at these upper-atmosphere waves (scroll down to Panel 2 on this page). The effect of these waves on atmospheric energy transport is a hot topic of research.

Golf ball-sized hail at the Earth’s surface is related to energy transport 100 km up in the atmosphere!


NOTE: This post has been updated since it was first written to clarify that the circular waves are likely not evidence of a bore, as was originally implied. They are more likely internal buoyancy waves, which are also known as gravity waves. For more information, consult your local library.

Rare Super Cyclone in the Indian Ocean

The Indian Ocean has just had its first Super Cyclone since 2007. The name of it is “Phailin” and I bet you just pronounced it incorrectly (unless you speak Thai). It’s closer to “PIE-leen” than it is to “FAY-lin”. The name was derived from the Thai word for sapphire. (If you go to Google Translate and translate “sapphire” into Thai, you can click on the “audio” icon {that looks like a speaker} in the lower right corner of the text box to hear a robotic voice pronounce it. You can also click on the fourth suggested translation below the text box and try to pronounce that as well.)

If you’re tired of reading about flooding in this blog, you’re probably going to want to avoid reading about Phailin. It already dumped up to 735 mm (28.9 inches) of rain on the Andaman Islands in a 72-hour period. Aside from the heavy rains, Phailin is a text-book example of “rapid intensification”, as official estimates of the storm’s intensity grew from 35 kt (65 km h-1 or 40 mph) when the storm was first named, to 135 kt (250 km h-1 or 155 mph!) just 48 hours later. Here’s a loop of what that rapid intensification looks like from the geostationary satellite, Meteosat-7. (Those are the Andaman Islands where the cyclone first forms.)

VIIRS being on a polar-orbiting satellite, it’s not possible to get an image of the cyclone every 30 minutes like you can with Meteosat-7. VIIRS only views a cyclone like Phailin twice per day. But, VIIRS can do things that Meteosat-7 can’t. The first is produce infrared (IR) imagery at 375 m resolution. (Meteosat-7 has 5 km resolution.) The image below is from the high resolution IR band, taken at 20:04 UTC 10 October 2013:

VIIRS high-resolution IR image of Super Cyclone Phailin, taken 20:04 UTC 10 October 2013

VIIRS high-resolution IR image of Super Cyclone Phailin, taken 20:04 UTC 10 October 2013

Look at the structure of the clouds surrounding the eye. (You’re definitely going to want to see it at full resolution by clicking on the image, then on the “3875×3019” link below the banner.) VIIRS is detecting wave features in the eyewall that other current IR sensors aren’t able to detect because they don’t have the resolution. The coldest cloud tops are found in the rainband to the west of the eyewall (look for that purple color) and are 179 K (-94 °C). That’s pretty cold!

Also notice the brightness temperature gradient on the west side of the eye is a lot sharper than on the east side of the eye. This is because the satellite is west of eye (the nadir line is along the left edge of the plotted data), looking down on the storm at an angle, revealing details about the side of the eyewall on the east side. Look down on the inside of a cardboard tube or a piece of pipe at an angle to replicate the effect. (Actually, the eye wall of a tropical cyclone slopes away from the center, so it’s more like funnel than a tube. If you go looking for a cardboard tube or a piece of pipe to look at, the results will be inaccurate. Grab a funnel instead.)

Another advantage of VIIRS is the Day/Night Band, a broadband visible channel that is sensitive to the low levels of light that occur at night. There is no geostationary satellite in space with this capability. The image below was taken from the Day/Night Band at the same time as the IR image above:

VIIRS Day/Night Band image of Super Cyclone Phailin, taken 20:04 UTC 10 October 2013

VIIRS Day/Night Band image of Super Cyclone Phailin, taken 20:04 UTC 10 October 2013

The Day/Night Band shows the eye clearly. Plus, being able to see the city lights gives an idea of the amount of people and infrastructure that are in the storm’s path.

Now, hold on a minute. 10 October 2013 was one day before first quarter moon, which means the moon was below the horizon when this image was taken. (Generally speaking, the moon is only up for nighttime VIIRS overpasses that occur from two days after first quarter to two days after last quarter.) If you want get more specific, India is one of the few places with a half-hour offset from most time zones (UTC +5:30), which means this image was taken at a local time of 1:34 AM 11 October 2013. Local moonrise time for the eastern coast of India for that date was 11:33 AM (10 hours later), while the moonset occurred 3.5 hours earlier (10:02 PM). This means you should be asking the obvious question: if there was no moonlight (and obviously no sunlight either, since this a nighttime image), why is VIIRS able to see the cyclone?

Was it the scattering of city lights off the clouds that allows you to see the clouds at night, like in this photo? No, because this cyclone is way out over the ocean, in the middle of the Bay of Bengal. Due to the curvature of the Earth, city lights won’t illuminate any clouds more than a few tens of kilometers away. The center of this storm is about 600 km away from any city lights and is still visible. At the most, only the very edges of the storm near cities would be illuminated if this were the case.

I can see at least two lightning strikes in the image, so is it lightning illuminating the cloud from the inside? No, it’s not that either. See how streaky the lightning appears? The whole storm would look like a series streaks, some brighter than others, depending on how close they were to the tops of the clouds (and how close the lightning was to the position of the VIIRS sensor’s field of view during each scan). The top of the storm is much too uniform in brightness for it to be caused by lightning.

So, if you’re so smart, what is the explanation, Mr. Smartypants? I’m glad you asked. It is a phenomenon called “airglow” (or sometimes “nightglow” when it occurs at night). You can read more about it here and here. The basic idea is that gas molecules in the upper atmosphere interact with ultraviolet (UV) radiation and emit light. Some of these light emissions head down toward the earth’s surface, are reflected back to space by the clouds, and detected by the satellite.

Really? Some tiny amount of gas molecules way up in the atmosphere emit a very faint light due to excitation by UV radiation, and you’re telling me VIIRS can see it? But, it’s nighttime! There’s no UV radiation at night! How do you explain that? The UV radiation breaks up the molecules into individual atoms during the day. At night, the atoms recombine back into molecules. That’s when they emit the light. Look, it’s in a peer-reviewed scientific journal if you don’t believe me. (A shortened press release about it is here.) Thanks to airglow (and the sensitivity of the Day/Night Band), VIIRS can see visible-wavelength images of storms at night even when there is no moon!

Getting back to the Super Cyclone, here’s what Phailin looked like in the high-resolution IR channel the next night (19:45 UTC 11 October 2012), right around the time where it reached its maximum intensity:

VIIRS channel I-05 image of Super Cyclone Phailin, taken 19:45 UTC 11 October 2013

VIIRS channel I-05 image of Super Cyclone Phailin, taken 19:45 UTC 11 October 2013

Here, the cyclone is much closer to nadir (the nadir line passes through the center of the image), so you’re more-or-less looking straight down into the eye on this orbit. The corresponding Day/Night Band image is below:

VIIRS Day/Night Band image of Super Cyclone Phailin, taken 19:45 UTC 11 October 2013

VIIRS Day/Night Band image of Super Cyclone Phailin, taken 19:45 UTC 11 October 2013

Once again, the cyclone is illuminated by airglow. (Some of the outer rainbands are also being lit up by city lights, which are visible through the clouds.) The only question is, what is that bright thing off the coast of Burma (Myanmar) that shows up in both Day/Night Band images? It looks like a huge, floating city. According to Google Maps, there’s nothing there. That is one question I don’t have the answer to (*see Update #2*).

Any other questions about cyclones in India? Check out this FAQ guide put out by the India Meteorological Department.

With a peak intensity estimate at 140 kts (259 km h-1 or 161 mph), Phailin was one of the strongest cyclones ever in the Indian Ocean. (Only 2007’s Gonu – 145 kt – was stronger. Several other storms have been estimated at 140 kt.) The last time a cyclone of Phailin’s intensity hit India, over 10,000 people died. Credit must be given to the Indian government, who successfully evacuated 900,000 people from the coast (the article refers to 9.1 lakhs; one lakh is 100,000), and so far, only about 25 people have been confirmed dead. In fact, fewer people were killed by this cyclone than were killed by a panicked stampede outside a temple in central India the same weekend.


UPDATE #1 (15 October 2013): The Day/Night Band also captured the power outages caused by Phailin. Here is a side-by-side comparison of Day/Night Band images along the coast of the state of Odisha (also called Orissa), which took a direct hit from the cyclone – a zoomed in and labelled version of the 10 October image above (two days before landfall) against a similar image from 14 October 2013 (two days after landfall):

VIIRS Day/Night Band images from before and after Super Cyclone Phailin made landfall along the east coast of India.

VIIRS Day/Night Band images from before and after Super Cyclone Phailin made landfall along the east coast of India.

Notice the lack of lights in and around the small city of Berhampur. That’s roughly where Phailin made landfall. Also, notice the difference in appearance of the metropolitan area of Calcutta. It almost appears as if the city was cut in two as a result of electricity being out in large parts of the city.


UPDATE #2 (15 October 2013): Thanks to Renate B., we’ve figured out the bright lights over the Bay of Bengal near the coast of Myanmar (Burma) are due to offshore oil and gas operations. Take a look at the map on this website. See the yellow box marked “A1 & A3”? That is a hotly contested area for gas and oil drilling, right where the bright lights are. It is claimed by Burma (Myanmar) and India, China and South Korea are all invested in it. China has built a pipeline out to the site that cuts right through Myanmar (Burma) that some of the locals are not happy about.


UPDATE #3 (16 October 2013): It was pointed out to me that the maximum IR brightness temperature in the eye of the cyclone in the 20:04 UTC 10 October 2013 image was 297.5 K (24.4 °C), which is pretty warm for a hurricane/cyclone/typhoon eye. It is rare for the observed IR brightness temperature inside the eye to exceed 25-26 °C. Of course, the upper limit is the sea surface temperature, which is rarely above 31-33 °C. And the satellite’s spatial resolution affects the observed brightness temperature, along with a number of other factors.

A warm eye is related to a lack of clouds in (or covering up) the eye, the eye being large enough to see all the way to the surface at the viewing angle of satellite, the satellite having high enough spatial resolution to identify pixels that don’t contain cloud, and the underlying sea surface temperature. Powerful, slow moving storms may churn the waters enough to mix cooler water from the thermocline up into the surface layer, reducing the sea surface temperature. Heavy rains and cloud cover from the storm may also lower the sea surface temperature. Phailin was generally over 28-29 °C water, and was apparently moving fast enough (or the warm water was deep enough) to not mix too much cool water from below (a process called upwelling).

It may or may not have any practical implications, but the high resolution IR imagery VIIRS is able to produce may break some records on warmest brightness temperature ever observed in a tropical cyclone eye.