Odd radius halo - 2 April

Veit has sent this odd radius halo from southern Germany. He took the photos on 2 April 2012 at 10:48 CEST. More of his halo images cane be viewed in his Panoramio gallery ( 1 )

Display from Achsheim

On the morning of 25th January 2012, I observed a large halo display near Achsheim, a little village north of Augsburg/Bavaria/Germany (450m elevation). Beside this village, there’s a little river called Schmutter. It’s not a skiing region and there are no snow cannons.

The day before it was cloudy and it was snowing a little bit, during the following night there weren’t any clouds and in the morning there was „normal“ fog. The minimum temperature in the night was about
5 °C below zero.

I don’t know when the halo display began, because when I reached this region full of ice crystals it existed already. And it still existed when I left the region (10:00 a.m). I took photos of it from about 9:25 until 10:00 a.m (CET).

You can see well the 22° halo, sun dogs, supralateral arc, the upper tangent arc, circumzenithal arc, tape arc, infralateral arc and last but not least the Moilanen’s arc. All phenomenas were seen all the time I was there. ( 1 - 2 - 3 )

Daniel Eggert

Helic and Tape arc in Cirrus

In the afternoon of October 14, I observed a large halo display in Bochum, Germany.
It started at 14.25 CET (15.25 CEST) with circumzenithal and supralateral arc. During the following minutes, also the upper tangent arc, a bright Parry arc and the 22°-halo appeared, followed by both sundogs and a faint upper circular Lowitz arc on the left side. ( 1 )

At 14.50 CET, I noticed a conspicuous white arc, forming a circle around the zenith together with the CZA. A closer look showed that this circle was not really circular, but rather had the shape of an American football.

This white arc grew longer and longer, an as ist passed the supralateral arc, it turned out to be the heliac arc, clearly visible in thin cirrus clouds.
At 14.55 CET, also the upper left Tape arc appeared as a bright colourful spot on the supralateral arc. At the same time, the left part of the Parry arc grew very long, almost reaching the supralateral arc, while its upper part faded away. ( 2 )

After 15.00 CET, the halo display slowly vanished, but before it faded away, left Lowitz arc was visible for about 10 minutes, as well as a very bright part of the parhelic circle. The display ended at 15.25 CET, having showed 10 different types of haloes with up to 8 being visible at the same time.

Peter Krämer, Bochum, Germany

Original post in Ice Crystal Halos

Subanthelion and diffuse subanthelic arcs

I took these pictures during the beginning of a flight from Paris to Washington DC on the 18th of September. It shows the subanthelic area. At first the subanthelion appeared alone ( 1 ).

Then a short time later subparhelic circle and diffused arcs appeared too for about 1 minute ( 2 ).

Later on the flight, I could observe some brightening in the subanthelic area but not as conspicuous as in the beginning of the flight

Nicolas Lefaudeux

Plate Arcs from Japan

These pyramidal crystal halos were observed by Anthelene over Sakaiminato city in West Japan. The most interesting features of this high cloud display are the 9°, 20°and 24° plate arcs. Marko Riikonen has made a simulation with HaloPoint2.0 ( 1 ), according to him, the 20° plate arc had been photographed only once or twice in high clouds before. More of Anthelene's images can be seen on her website: http://bluemomenttime.blog89.fc2.com/blog-entry-442.html

Pyramidal halos over Frankfurt am Main

Andreas Zeiske observed a pyramidal halo on 6 June 2011 in Frankfurt am Main. In the images, the 22° halo, 18° halo and the left 18° lateral arc can be seen about the St.-Katharinen-Church. The phenomenon formed on a thin field of Cirrus clouds and lasted for 10 minutes at around 08.00 CET. About 5 hours later a cold front with rain showers and thunderstorms swept across the city of Frankfurt. ( 1 - 2 )

Andreas Zeiske, Germany

Atmospheric Phenomena Blog

The blog on atmospheric optics has moved to a new address ( 1 ), and has recently been updated with many interesting observations. As a teaser, Michael Großmann's image of a tertiary order rainbow can be seen on the right.

Pyramidal halo from Thailand

The above image was photographed by Pitan Singhasaneh on 5 June in Bangkok, Thailand.

Simultaneous upper tangent arc and rainbows

On 4 June 2011 Pietari Puranen observed these rainbows in Jyväskylä. When he turned around to see the sky around the sun, he observed an upper tangent arc. Remarkably, the arc formed in virga precipitating from the same low clouds around the rainbow forming cumulonimbus. It is rare to see halos in virga so close to rainbows.

As column crystals are formed in temperatures relatively close to 0 degrees Celsius we may assume the Virga has been born in temperatures around, say, -4 to -9 degrees Celcius. At least in those temperatures diamond dust close to the ground seems to most often exhibit column crystals.

Double sun effect

On May 1st 2011 cumulonimbus clouds precipitating hail were commmon. These clouds exhibited clear praecipitatio and later in the evening they featured prominent virga. In these virga a sun pillar formed and as the sun descended behing stratocumulus a double sun effect was seen. A series of images is provided to see the progression of the effect. The real sun can be seen descending behing the stratocumulus.

The first observation of this effect was by Giovanni Cassini in 1693 (see e.g. Riikonen 2011 (1)). By clicking the above image a larger version can be seen. A full image gallery is available online (2). Marko Riikonen also captured images from the other side of the lake (3).

Liljequist superparhelia & a nucleation agent gun

This Liljequist superparhelia was observed in the spotlight beam on 5 January 2011. The lamp is about a degree or two below the horizon, thus giving the central stage to the Liljequist superparhelia. The Liljequist parhelia can be seen against the snowy ground below the superparhelia.

The halos were seen in diamond dust that was generated by my water ice nucleation agent gun operating ca. 1 kilometer away from the site of the observation. The nucleation agent gun can operate autonomously for hours since the water supply is automated. The temperatures varied between -22 and -27 degrees Celsius.

The image above shows some colour artefacts (the background sky is not even color) as we were also testing Riikonen latest HID lamp (Marko Riikonen accompanied me during this night) that has two high intensity discharge bulbs. Unfortunately we were only able to fire up one bulb. Two bulbs would have produced a more even beam in terms of colours and luminosity.

Full image gallery is available (1). It also contains a lengthier account on the evening.

The nucleation agent gun can be seen in action in a separate photo gallery (2).

Atmospheric optics meeting of 2011 in Finland

Finnish Atmospheric optics enthusiasts met on 27-29 May 2011 in the Artjärvi observation centre. The topics of the presentations varied from the latest scientifical results in NLC research and simulation of higher order rainbows to the polar expeditions and observations of optical phenomena in the 18th century. The full programme is available (<a href="http://www.ursa.fi/wiki/Ilmakeh

Elliptical halo from 22 January 2011

Midday Altocumulus move thru the area and while passing through, I get a fine corona around the sun and later on lenticular cloud formations pass through showing fine iridescence. With sun getting sort of low, more AC roll in precipating into a layer of ice crystals which forms a tall ellipse that's complete and lasted for over an hour. I got some nice pics of the display and this is a good way to start the new halo year ( 1 - 2 ).

Michael Ellestad

Lowitz arcs from Florida

Nick Beck has sent this high cloud halo display that he observed on Christmas eve in Florida. The sun elevation was 31 degrees when it started and the display ended when the sun was 7 degrees above the horizon, lasting a little over 3 hours. The observed halos include Lowitz, upper sunvex and suncave Parry arcs ( 1 ), possible Wegener ( 2 ) and helic ( 3 ) arcs, and infralateral arc ( 4 ),among others ( 5 - 6 - 7 - 8 - 9 - 10 - 11 )

"Upper parhelia" over the Alps

On 13 December it was cold and windy on Mt. Wendelstein (1838m) in the German Alps with temperature of -17°C and huminity over 90%. The whole day ice dentrids glittered in the air ( 1 ). For 6 hours I could observe a partly bright subsun ( 2 ). Actually I've seen 2 subsuns in time, the "main subsun" at a lower blanket of clouds and a second displaces a bit to the right in near crystals, based on tilted ice plates (caused by the wind). It was very difficult to photograph it because of the radiant brightness of "main subsun", but you can see the second, as the "main subsun" disappeared a short time. ( 3 - 4 - 5 )

Partly shaped imaginary arcs on this: ( 6 )

A short time before sunset in a single cirrus cloud was formed a colourful parhelia. ( 7 - 8 - 9 )

It faded a short time before sunset at 16.17 CET. ( 10 )

From 16.25 to 16.35 CET the parhelia clearly appeared again in the same Cirrus stripes. ( 11 - 12 - 13 - 14 - 15 )

I've not a explanation for this. I've observed a little displaced parhelia in far-off Cirrus (1-2deg) a couple of times, but never before such a clear sundog to this negative altitude.

Claudia Hinz

Helic and Wegener from Brandbergen

The halo was observed in Brandbergen 20 km south of Stockholm Sweden. Time for the display was 1-dec-10 9:50 - 10:50 AM. There were snow guns running at two ski-slopes both of them 20 km away. I don’t know if they had some influence.

Halos observed were

- supralateral arc
- 46 degree halo
- Circumzenital arc
- upper sunvex Parry
- Upper tangent arc
- Wegener arc
- Parry supralateral arc (Tape)
- 22 degree halo
- parhelic circle
- helic arc

More images can be seen if you click on the image above.

Mats Mattsson

Halo display from Upper Bavaria

On 27.11.2010 from 09.30 till 13.30 CET Claudia and Wolfgang Hinz could observe the depicted halo phenomena, comprising not less than 22 types of halos, in the German Alps of Upper Bavaria ( 1 ):

- 22deg halo
- left and right parhelia
- upper and lower tangent arc
- upper and lower sun pillar
- circumzenithal arc
- 46deg halo
- parhelic circle
- upper, lower and circular Lowitz arcs
- Anthelion
- 120deg parhelia
- supralateral arc
- infralateral arc
- upper suncave Parry arc
- subsun
- left and right subparhelia
- Wegener anthelic arc
- Hastings anthelic arcs
- upper and lower Tape arcs (46deg Parry)
- heliac arc
- subhelic arcs
- Moilanen arc

The types of halos and their brightness sometimes changed within minutes.

Location and weather situation:

The halo phenomena occured in the Sudelfeld, which is a mountain saddle at an altitude of ca. 1100 m. Low stratus clouds drawing in from the Inn River valley dissolved there and fell out in ice crystals. The Sudelfeld being a popular skiing resort, this morning two snow making machines ("snow guns") were also working, but shut off near 11 o'clock. Jari Luomanen suggests that the snow gun produced nucleation agents also took part in the nucleation process of the stratus which then continued even after the guns stopped operating.

Claudia Hinz

Moon halos from Mustavaara ski resort

It's better to be inside a punch hole cloud than just look at it. On the night of 17/18 November snow guns seeded a punch hole in low stratus cover at Mustavaara ski resort in Eastern Finland. Plate crystal dominated halo display appeared in the resulting diamond dust. Temperature on the ground was -9° C. In the image above, moon elevation is 32.7°.

Marko Riikonen

Original post in Submoon

Superb Lowitz and helic arcs from the USA

The display was seen at and/or just after high noon from eastern Nebraska about 41 degrees north, on November 7. My sister had called about some geese at a refuge nearby and wanted to go photograph them. I was going to visit my parents, like I often do, and decided I may as well take my camera gear with so if I went to the refuge I'd not have to stop back home. This is the only reason I even had photo gear with me. I stepped outside to do something, and right away saw the parhelic circle extending out a ways, something I've never seen before and I have at least seen a number of optics displays now (lunar fog bows, light pillars, lunar vivid coronas, etc)....so I look often enough for stuff. I pointed it out to my uncle as I sprinted for my car to get my gear and he thought, "it's not just a cloud". I said no, it's an arc, watch. I took my camera and sprinted up the hill behind the house.

I soon was seeing "sun dogs" on the parhelic circle. I then was clearly seeing the Wegener arc inside the parhelic circle. It was very vivid as with my eyes I could clearly see the rainbow colors. To be honest I never did see the Heliac arc before. I was flipping through pictures inside later and it simply jumped out. I was like, what is that arc..then looked it up.

The top of the 22 degree halo visually looked crazy most of the time. Very clear and colorful and odd arcing. I thought it was just an intense circumscribed arc in there but it didn't look placed right and like more was happening. ( 1 - 2 - 3 - 4 - 5 )

The show only lasted 30-40 minutes I'd guess. Then it was pretty hard to get any optics at all. What was strange was visually nothing much was changed about the sky. I was watching for hours so there were different periods of less contrail garbage blocking out the sun. I had friends in Omaha, 20 miles south, and Lincoln another 45 miles south of that, looking too. They never saw anything good. They watched till sunset too, but they also didn't get out as soon as I was and that was the best part. I wonder what I missed before I got out.

The satellite loop for that day may give the key ( 6 ). I'm located in eastern NE which is at the top center. It was much like the crystals you get right behind a blizzard in air just where it is clearing behind the storm. You can see a more puffy nature to the clouds, they pass and the ice crystals are left in the air. That stuff on satellite is below typical cirrus level/flight level...but still up there. It for sure was different than normal cirrus. A lot of that "cirrus" in the shot is left over form all the contrails. Once the sun got lower you could see the moisture/clouds clearly below the contrails. So anyway, probably worth noting the clouds coming across at the time were more along the lines of mid-level clouds/moisture.

Mike Hollingshead

Superb diamond dust display in Austria

On 18 October 2010 a superb diamonddust halodisplay was observed at the meteorological station Sonnblickobservatorium ( 1 ) in the Austrian Alps (3106 m, 12°57’ E, 47°03’ N). Hermann Scheer, member of the meteorological team at the observatorium, took images of 13 different haloforms between 08:30 and 09:00 CEST (06:30 and 07:00 UT): parhelia, 22°-halo, 46°-halo, lower tangent arc, subsun, subparhelia, infralateral arc with Parry-infralateral arc, supralateral arc, parhelic circle, subparhelic circle, subhorizon Wegener arc and helic arc. ( 2 - 3 - 4 - 5 - 6 ) The images were taken at a sun elevation of 8,9° to 10,3° between 08:31 and 08:40 CEST, the file names indicate the exact time.

The brightness of the Wegener arc was incredible. Very interesting is the combination of Parry-infralateral arc with infralateral and faint supralateral arc. This part of the phenomenon is similar to an observation in the Czech Republic (26th of December, at Lysa hora in Krkonose (Giant Mountains)), described at Optické Úkazy v Atmosférè ( 7 - 8 ) Thanks to Tomas Trzicky for the links. And also in Ice Crystal Halos ( 9 ). In this very small area of the display we can see a 46°-halo, Wegener arc, helic arc and the subparhelic circle too.

The display was observed at the upper boundary of the stratiform layer; weather conditions: 06:00 UT - air temperature -6,8°C, air relative humidity 96%.

Credit to Hermann Scheer for giving the permission to show his images at Crystal Halos Blog under this licence: ( 10 ). Homepages of Hermann Scheer: ( 11 - 12 - 13 ). This diamond dust display is described on the page "Atmospheric phaenomenons observed in Austria" too: ( 14 )

Karl Kaiser