Contrail or cloud?
Forum rules
These topics are a read-only archive and may be subject to out-of-date information.
For today's weather discussion head to: New Zealand Weather & Climate
These topics are a read-only archive and may be subject to out-of-date information.
For today's weather discussion head to: New Zealand Weather & Climate
-
- Posts: 4
- Joined: Sun 30/01/2005 14:14
- Location: Auckland
- Has thanked: 0
- Been thanked: 0
- NZstorm
- Posts: 11333
- Joined: Mon 10/03/2003 19:38
- Location: Grey Lynn, Auckland
- Has thanked: 342 times
- Been thanked: 361 times
celica
The only cloud cover(moisture layer) over Auckland last night was an overcast layer of thin Cirrostratus at about 9000m. Winds at that level were SW at 25kts.
The only possible cause for such a line through the cloud (other than a hoax???) would be an aircraft passing through our region at cruising level and then doing a u-turn.
The only cloud cover(moisture layer) over Auckland last night was an overcast layer of thin Cirrostratus at about 9000m. Winds at that level were SW at 25kts.
The only possible cause for such a line through the cloud (other than a hoax???) would be an aircraft passing through our region at cruising level and then doing a u-turn.
- Storm Struck
- Posts: 4871
- Joined: Wed 17/11/2004 21:25
- Location: Belfast Christchurch
- Has thanked: 23 times
- Been thanked: 393 times
Could be a smoke ring this depends on where you took this photo it may be an area of smoke mixed with smog on the edge of the Auckland city.
Sometimes if winds are blocked in many areas or variable one day winds can overlap causing these rings.
It happend in New York once in the late 1900's.
Welcome there I see you are new.
Cheers
JASON TIPPET.
Sometimes if winds are blocked in many areas or variable one day winds can overlap causing these rings.
It happend in New York once in the late 1900's.
Welcome there I see you are new.
Cheers
JASON TIPPET.
-
- Posts: 4
- Joined: Sun 30/01/2005 14:14
- Location: Auckland
- Has thanked: 0
- Been thanked: 0
nope, this is not a hoax... and yeah I'm new, this'll most likely be the only time I'll visit this site as i dont have much of an interest in weather generally
I've got plenty more pictures and several other people that saw it too
It was last night at about 9pm i think looking from mt wellington looking very roughly eastwards over panmure
Thats not really a U turn though is it... I would'nt want to be in the Boeing 747 making that manouver... more of a 360 degree turn
Just thought I'd post this up because between us we couldnt decide what the cause of it would be
I've got plenty more pictures and several other people that saw it too
It was last night at about 9pm i think looking from mt wellington looking very roughly eastwards over panmure
Thats not really a U turn though is it... I would'nt want to be in the Boeing 747 making that manouver... more of a 360 degree turn
Just thought I'd post this up because between us we couldnt decide what the cause of it would be
-
- Posts: 9920
- Joined: Sun 29/06/2003 22:39
- Location: Mt Eden Auckland
- Has thanked: 856 times
- Been thanked: 870 times
Thanks Celica for the Photo.
It is either Aliens from another World trying to send us a message or it has been created by Aircraft. The sky area over East Auckland and beyond is where Aircraft circle for landing or taking off from Auckland Airport.
North Easterlies last night would have had Australia bound Aircraft taking off into the Eastern sky and then doing a sharp U turn to head West out over the Tasman.
It is either Aliens from another World trying to send us a message or it has been created by Aircraft. The sky area over East Auckland and beyond is where Aircraft circle for landing or taking off from Auckland Airport.
North Easterlies last night would have had Australia bound Aircraft taking off into the Eastern sky and then doing a sharp U turn to head West out over the Tasman.
-
- Posts: 18493
- Joined: Wed 12/03/2003 22:08
- Location: Raukapuka Geraldine
- Has thanked: 1771 times
- Been thanked: 1415 times
Hi Celiacelica_tommo wrote:nope, this is not a hoax... and yeah I'm new, this'll most likely be the only time I'll visit this site as i dont have much of an interest in weather generally
I've got plenty more pictures and several other people that saw it too
It was last night at about 9pm i think looking from mt wellington looking very roughly eastwards over panmure
Thats not really a U turn though is it... I would'nt want to be in the Boeing 747 making that manouver... more of a 360 degree turn
Just thought I'd post this up because between us we couldnt decide what the cause of it would be
My thought is to send it to someone in NAZA in the USA
Could be a foreign body/something from outer space.
I don't think it is weather related.
JohnGaul
NZTS
- NZstorm
- Posts: 11333
- Joined: Mon 10/03/2003 19:38
- Location: Grey Lynn, Auckland
- Has thanked: 342 times
- Been thanked: 361 times
The only cloud in the sky yesterday evening was cirrostratus and the soundings are quite accurate at detecting the heights of such moisture lasyers. The moisture actually starts around 8400m.NZstorm, I think the cloud layer last night must have been much lower than 9000m
As for the possibility of such high level u-turns, yes aircraft may turn sharply like this.
The fact that the phenomena lasted an hour indicates to me it is high level
and this ties in with our observation of high level moisture.
- Willoughby
- Site Admin
- Posts: 4433
- Joined: Sat 14/06/2003 16:18
- Location: Darwin, Australia: Storm city
- Has thanked: 264 times
- Been thanked: 288 times
- Contact:
-
- Posts: 4
- Joined: Sun 30/01/2005 14:14
- Location: Auckland
- Has thanked: 0
- Been thanked: 0
- TonyT
- Moderator
- Posts: 2883
- Joined: Thu 08/05/2003 11:09
- Location: Amberley, North Canterbury
- Has thanked: 354 times
- Been thanked: 1156 times
Some thoughts. Contrails are easily blown by local winds. So the shape seen in the photo is not necessarily the shape of the flight path of the aircraft. We cant be sure its a plane flying in the CS layer, or in fact flying above, generating a contrail cloud and having a shadow cast on the CS layer below. I have seen this several times. If it is a contrail above the CS then with the time of night it could be some distance away, the shadow angle will be quite large and it may appear rather distorted.
If we assume it is in the CS layer, and the CS is at 8400m as Steven suggests, then if we know where the photo was taken from, where it is looking towards, and can guess the elevation angle of the contrail, then we can triangulate how far away the contrail is, ie its ground position. The way to do this is to go back and stand in the same place you took the photo, estimate the elevation angle of the top and bottom of the contrail (the telegraph poles provide a useful reference in this case) and the angular width of the contrail. The rest is straightforward trigonometry.
If we assume it is in the CS layer, and the CS is at 8400m as Steven suggests, then if we know where the photo was taken from, where it is looking towards, and can guess the elevation angle of the contrail, then we can triangulate how far away the contrail is, ie its ground position. The way to do this is to go back and stand in the same place you took the photo, estimate the elevation angle of the top and bottom of the contrail (the telegraph poles provide a useful reference in this case) and the angular width of the contrail. The rest is straightforward trigonometry.
-
- Posts: 4
- Joined: Sun 30/01/2005 14:14
- Location: Auckland
- Has thanked: 0
- Been thanked: 0
-
- Posts: 133
- Joined: Mon 31/01/2005 18:57
- Location: South Auckland
- Has thanked: 0
- Been thanked: 0
Hi Everyone
I've just joined and I must say what a wonderful, informative forum it is.
I've been involved with meterology in the past and still hold an active interest in it with my current job working at Auckland Airport.
In answer to the unusual sight over Auckland on Saturday night. It was an Air NZ Boeing 737-300 carrying out a test flight at 35000ft following a major maintenance check in Auckland. Usually these checks take place in Christchurch but a couple of times a year end up being done in Auckland.
Regards
Mike
I've just joined and I must say what a wonderful, informative forum it is.
I've been involved with meterology in the past and still hold an active interest in it with my current job working at Auckland Airport.
In answer to the unusual sight over Auckland on Saturday night. It was an Air NZ Boeing 737-300 carrying out a test flight at 35000ft following a major maintenance check in Auckland. Usually these checks take place in Christchurch but a couple of times a year end up being done in Auckland.
Regards
Mike
- Storm Struck
- Posts: 4871
- Joined: Wed 17/11/2004 21:25
- Location: Belfast Christchurch
- Has thanked: 23 times
- Been thanked: 393 times
-
- Posts: 759
- Joined: Wed 03/12/2003 15:44
- Location: Dunedin, NZ
- Has thanked: 0
- Been thanked: 11 times
- Contact:
Such a "normal" explanation from someone with a user name "Area 51"
Welcome aboard Mike... thanks for the info
Welcome aboard Mike... thanks for the info
There is no such thing as bad weather, just the wrong clothes.
-
- Posts: 18493
- Joined: Wed 12/03/2003 22:08
- Location: Raukapuka Geraldine
- Has thanked: 1771 times
- Been thanked: 1415 times
Horray, now we can go off to our beds and wonder when the next ENE gales will strike??Area51 wrote:Hi Everyone
I've just joined and I must say what a wonderful, informative forum it is.
I've been involved with meterology in the past and still hold an active interest in it with my current job working at Auckland Airport.
In answer to the unusual sight over Auckland on Saturday night. It was an Air NZ Boeing 737-300 carrying out a test flight at 35000ft following a major maintenance check in Auckland. Usually these checks take place in Christchurch but a couple of times a year end up being done in Auckland.
Regards
Mike
JohnGaul
NZTS