What caused the strange doppler-radar images captured in these photos?

[PIT2]

Does anyone know what could have caused these kinds of doppler-radar images:

http://img452.imageshack.us/img452/909/ind23br.gif

More radar images of the same event:
http://www.softspotopening.com/

 

[waht]

Looks like it originated from Indianapolis. I have one word: NASCAR

 

[scott1]

It's moves out.It could the jetsterm(or somthing elese) breaking up the storm.That line appers in the east is probally just an error by the radar

 

[russ_watters]

I don't see anything weird in that gif - to what are you referring?

 

[Evo]

I don't see anything weird in that gif - to what are you referring?

Thanks, I was wondering if I was the only one that wasn't seeing things.

 

[K.J.Healey]

I believe they refer to the single radar photo in the time sequence that has a NE direction line. Looks like simple doppler radar error to me. Its basically originating at the doppler station in the city and cuts for a few degrees along its scan path. Probably just a coloring error due to a reset or something.

There are also rings. Don't know what those could be other than coloum shaped clouds with majority moisture on the outside? remember weather doppler measures a lot of things, but I am pretty sure metallic flying objects and wromholes aren't one of them.

 

[PIT2]

The weird things are those large rings appearing.
Apparently it was weird enough to make the newspaper:

http://www.softspotopening.com/Article.bmp

 

[russ_watters]

I'm not a meteorologist, but they look like thermals to me. Thermals are literally bubbles of warm air.

 

[Evo]

According to the article it's caused by birds. The meteorologist & his colleagues say they witness this about 3-4 times a year. What they thought was unusual was it was a bit early in the year for the birds to be migrating, but it did appear to be birds.

 

[PIT2]

So far we've got:

-birds (which according to the paper happens 3 or 4 times a year, but here its 5 times in 90 minutes - in the wrong season)
-thermals (anyone know how large these get? - I believe 45 miles is a bit large for a thermal(or for birds))
-nuclear bombs

Any other options?

 

[Aether]

-thermals (anyone know how large these get? - I believe 45 miles is a bit large for a thermal(or for birds))

I have studied thermals, and find russ_watters' suggestion to be an interesting one. Basically, warm air at the surface of the Earth will rise if/when the vertical temperature profile of the air above the surface is colder than about 4 deg. F/1000 ft.. Warmer than that, and you have a 'temperature inversion' which supresses thermals. The patern on the radar map could be consistent with a fast moving cold front descending from north to south across the area. It would be interesting to see the weather charts for this region at this time to see if such a cold front passed through.

Thermals can be any size. The whole Earth is continually involved with thermal convection on a global scale...

Global Scale Circulation of the Atmosphere: http://www.physicalgeography.net/fundamentals/7p.html

 

[Garth]

So far we've got:
-birds (which according to the paper happens 3 or 4 times a year, but here its 5 times in 90 minutes - in the wrong season)
-thermals (anyone know how large these get? - I believe 45 miles is a bit large for a thermal(or for birds))
-nuclear bombs
Any other options?

Coronal mass ejections hitting the Earth?

Garth

 

[russ_watters]

I'm not a big fan of the birds theory - a 45 mile circular formation would have to contain millions of birds. And it is a little big for a thermal, too, but when thunderstorms form, the cloud tops can really spread out. The 4th pic down here is probably on the order of about 20 miles in diameter. http://www.physicalgeography.net/fundamentals/7t.html

But then also, it's something like 5:00am, which is early for thunderstorm/thermal activity.

 

[Ivan Seeking]

Here is the weather data for Fort Wayne that day
http://weather.fortwayne.com/auto/fortwayne/history/airport/KFWA/1996/8/2/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

If it was cold it would be easier to explain. However, note that the temp dips to the day's low from 5 to 6 AM, and the wind goes to zero from 4 to 6AM. The event duration is from about 5:30 to 7:00, EST.

I have driven through those areas, much of which are mostly covered with corn fields, and there is a good deal of irrigating done. Perhaps this plays a role somehow...

 

[Ivan Seeking]

Something else is that the dew point is hovering just below the temp through those hours. A slight variation in either would result in saturation.

 

[PIT2]

I have driven through those areas, much of which are mostly covered with corn fields, and there is a good deal of irrigating done. Perhaps this plays a role somehow...

On this page they show that plowed flieds create thermals:
http://www.aerospaceweb.org/question/nature/q0253.shtml

There are also things called 'ring vortices', but they are also not this big:
http://sodar.obninsk.org/Vortex/Vortex1e.htm

How about exploding meteors?

 

[russ_watters]

Far too slow (not to mention, no damage...) to be exploding meteors.

 

[Aether]

The "Legend (dBZ)" scale is fluctuating from one frame to the next. Someone could be calibrating the system? -- http://img452.imageshack.us/img452/909/ind23br.gif

The archived NEXRAD Level-II (base data) files are available here: http://www.ncdc.noaa.gov/oa/radar/radardata.html. I have downloaded the files, but haven't been able to view them yet.

 

[Aether]

I have also (e.g., in addition to the data from the Indianapolis, IN radar station) downloaded (from the NCDC) the archived NEXRAD Level-II radar data for the time period in question which was recorded from Cincinnati, OH. Since the field of view for both of these radar stations overlap in the area where the anomalies occur, this might help sort out what went on there.

How much do you want to bet that I can't make Mickey Mouse appear (on a NEXRAD radar image) in the clouds over Evansville?

 

[Aether]

Wow! There appears to be something really going on within the atmosphere here.
Here is the Indianapolis, IN (KIND) NEXRAD (velocity) image for 19960802_105737:
And here is the Cincinnati, OH (KILN) NEXRAD (velocity) image for 19960802_105702:

The concentric rings on the display are 50km apart.

 

[BobG]

Here's a good site that talks about the typical anomalies that NEXRAD radar sites experience: http://www.letxa.com/anomalysunburst.php

The rings are usually caused by birds and normally occur around sunrise or sunset. Indianapolis is 5 hours behind GMT during Daylight Savings Time, so the rings are occurring at just about sunrise. In fact, you can tell when sunrise is within 10 minutes by the "beam" that seems to shoot out. The "beam" will be pointed directly at the Sun. Sunrise occurred at 5:44 local time (10:44 GMT) in Indianapolis on Aug 2, 1996. Several scans are combined into one image of useful data, so each image encompasses the entire previous 10 minutes of data.

The pictures of the velocity are interesting, as well. Here's a link that shows how to interpret the velocity: Doppler radar velocities

The blue and green areas represent wind headed towards the radar while the red and yellow are headed away from the radar. The radar normally picks up reflections from water (rain or snow) and the wind is determined by the direction and speed of the precipitation.

 

[Aether]

The rings are usually caused by birds and normally occur around sunrise or sunset.

I vote for the "birds". -- http://www.uwsp.edu/cnr/faculty/russell/KR%20Russell%20Radar.htm

 

[BobG]

Even if their relationship to UFOs is a hoax, the images and explanations are pretty fascinating. Interesting thread.

 

[Moonbear]

The timing seems consistent with bird behavior too. They start to wake up during the period of twilight just before sunrise.

Though, thunderstorms aren't too far-fetched at that time of year in that part of the country either. During the time I lived in Cincinnati, we had quite a few early morning thunderstorms in the late summer...they were the bands of storms still passing through that started overnight, though it would usually be the very end of the storms.

 

[Ivan Seeking]

Funny... Is it just a fluke with my computer or is most of the state of Indiana missing on Google Earth? I was going to look for any topological features that might map to the doppler images, but Indiana ain't there! Now how is that for conspiracy fuel... I do see Indianapolis, but the rest of the state is just gray.

I think there is a chance that I messed up Google by zooming around too quickly.

 

[Ivan Seeking]

Okay, how about a compromise? I wonder if large numbers of birds taking flight can trigger a storm in a saturated atmosphere...

 

[Aether]

Okay, how about a compromise? I wonder if large numbers of birds taking flight can trigger a storm in a saturated atmosphere...

I've seen airplanes landing in saturated (super-saturated?) air, and contrail-like streamers were trailing from their wings. Condensation releases a significant amount of latent heat, and that is primarily what makes thunderstorm clouds grow.

 

[Moonbear]

Funny... Is it just a fluke with my computer or is most of the state of Indiana missing on Google Earth? I was going to look for any topological features that might map to the doppler images, but Indiana ain't there! Now how is that for conspiracy fuel... I do see Indianapolis, but the rest of the state is just gray.
I think there is a chance that I messed up Google by zooming around too quickly.

I haven't looked up Indiana, but there are places that still have missing data where I've run into that problem too, at least if you zoom in too far.

 

[Ivan Seeking]

Now that I'm on my other computer it works fine. Apparently the zoom had locked up.

I was looking at Google Earth and comparing the terrain and other features to the locations of the bursts, and nothing really jumps out except perhaps that where we find a burst, I tend to see a boundary between farmland and developed land.

In any case, the atmosphere was likely saturated and I would imagine that any number of triggers might come into play.

 

[Ivan Seeking]

Well, I checked with a professional meteorologist.

I looked at the link. These are in fact roosting bird echoes. Pretty common to see them at sunrise and sunset on radars in the midwest. Also notice the sunrise spike pointing to the northeast... this is the radar picking up false echoes from the sun when it is low on the horizon pointing into the radar. The sun emits radiation at all frequencies.. including that of the radar.