The Naked Scientists

The Naked Scientists Forum

Author Topic: Jet Stream Joy !  (Read 19215 times)

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Jet Stream Joy !
« on: 10/09/2007 20:40:58 »
Dearest Jet Stream Jexperts of Acadamecally  Windy Luff & Joy,

This is the Jet Stream:






Nice isn't ?...but notice how there are no jets and certainly no small rivers ! (ie: Streams)..

....So..what IS the Jet Stream ?...How fast does it go ?..is it consistent ?

I had beans tonight.......have formed my own Jet Stream in my shorts !! ;)



 

another_someone

  • Guest
Jet Stream Joy !
« Reply #1 on: 11/09/2007 00:16:53 »
It is a consequence of the Earth spinning in space, and the viscosity of the air.

If you think of the Earth as a spinning body, and space beyond the Earth as stationary, then the atmosphere that is near to the Earth will spin with with the Earth, while the top of the atmosphere, near space, will be approximately static (simplification, both because there is no clear boundary between space and the Earth's atmosphere, and because of the low friction of space - but it makes a good starting point - I'll let someone shoot me down and fill in the details here).

Since our point of reference is the surface of the Earth, thus even though it may be that to someone viewing us from space will see the jetstream as moving only slowly around the Earth, while the air at the surface of the Earth will appear to be travelling around 1000mph near the equator, but to our point of reference, which is the Earth itself spinning at 1000mph, this surface air appears almost stationary to us, and the jetstream high up appears to be the thing in motion.
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
Jet Stream Joy !
« Reply #2 on: 11/09/2007 07:57:33 »
That sounds good until you consider that the direction of the jet stream is the same as that of the Earth. In Neil's graphic, the arrows are pointing in the direction of the Earth's rotation.

Your explanation would be ok were either the Earth or the jet stream (but not both) going the other way.
 

another_someone

  • Guest
Jet Stream Joy !
« Reply #3 on: 11/09/2007 16:39:37 »
That sounds good until you consider that the direction of the jet stream is the same as that of the Earth. In Neil's graphic, the arrows are pointing in the direction of the Earth's rotation.

Your explanation would be ok were either the Earth or the jet stream (but not both) going the other way.

OK, ignore what I have said - it is total and utter nonsense (should anybody be surprised  [:I]).
 

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Jet Stream Joy !
« Reply #4 on: 11/09/2007 17:47:45 »
*le sigh*

Do we really need rank amateurs on the site !! ? ;) ;)
 

Offline Karen W.

  • Naked Science Forum GOD!
  • *******
  • Posts: 31653
  • Thanked: 5 times
  • "come fly with me"
    • View Profile
Jet Stream Joy !
« Reply #5 on: 11/09/2007 18:34:24 »
LOL you guys are all funny! LOL!
 

paul.fr

  • Guest
Jet Stream Joy !
« Reply #6 on: 12/09/2007 16:32:03 »
There are actually 2 types of jet, the polarfront and the subtropical. the polar front jet is what we have over the uk, although the us has both. The subtropical at the southern border, and the polar along the northern states.

Jetstreams move west to east as well as noth to south, airlines will often use the jets to speed up flight times.

Those moving west to east are caused by the earths rotation, which i think is what George was describing. Those that move north to south are following the boundary between warmer and colder air. This where weather fronts generally develop.

the north - south jets also transport excess heat from the equator towards the poles, and then bring cold polar air back.

Again, Neil asks a very complicated weather question. The jets also play a part in el nino, causing tornadoes and all sorts of weather related events. If only i had the time....
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
Jet Stream Joy !
« Reply #7 on: 12/09/2007 22:56:49 »
That sounds good until you consider that the direction of the jet stream is the same as that of the Earth. In Neil's graphic, the arrows are pointing in the direction of the Earth's rotation.

Your explanation would be ok were either the Earth or the jet stream (but not both) going the other way.

OK, ignore what I have said - it is total and utter nonsense (should anybody be surprised  [:I]).

Now I feel guilty  :(
 

paul.fr

  • Guest
Jet Stream Joy !
« Reply #8 on: 14/09/2007 21:43:16 »
i have a little time to go in to this again. You asked "how fast does it go", well the average jet stream speed in the winter is around 125 - 160 mph, in the northern hemisphere, no idea about the southern.

Although in your picture there is only one jet of each (main) type, curiously the first type is called the "midaltitude" jetstream and not the polar jet. there can actually be more than one at the same time.

They are formed in breaks in the tropopause and there can be more than one break, resulting in two or even 3 jets. Sometimes a single jet can split in to 2 separate jets. When this splitting occurs it prevents cold air reaching much of the ground and as a result we get warmer weather. Weak polar jets and the almost lack of a subtropical jet, is one reason why we have a warm summer.

Of course the is so much more that can be said about jets but my crash course in meteorology, and weather forecasting was a long time back in college, and jets were not too well covered.

Aside from the two main jets, there are also Polar Night Jets which form in the winter, and weak Tropical Easterly Jets that form over....erm..places that have monsoons. I have just gone blank, and can't think of a place that has monsoons! oh well, I'm sure you know where they happen.
 

Offline Karen W.

  • Naked Science Forum GOD!
  • *******
  • Posts: 31653
  • Thanked: 5 times
  • "come fly with me"
    • View Profile
Jet Stream Joy !
« Reply #9 on: 01/10/2007 20:14:43 »
The monsoons influence the climates of India, Bangladesh, Southeast Asia,

and, to a lesser extent, northern Australia  and Central Africa.  For the most part, the

most prominent form of the monsoon climate is found on the Indian subcontinent.
 

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Jet Stream Joy !
« Reply #10 on: 01/10/2007 22:08:03 »
FANTASTIC INFO...THANKS
 

Offline neilep

  • Withdrawnmist
  • Naked Science Forum GOD!
  • *******
  • Posts: 20602
  • Thanked: 8 times
    • View Profile
Jet Stream Joy !
« Reply #11 on: 01/10/2007 22:09:22 »
The monsoons influence the climates of India, Bangladesh, Southeast Asia,

and, to a lesser extent, northern Australia  and Central Africa.  For the most part, the

most prominent form of the monsoon climate is found on the Indian subcontinent.

There's a monsoon in my pants after I've had an Indian !!..forms it's own subcontinent too !!
 

Offline Karen W.

  • Naked Science Forum GOD!
  • *******
  • Posts: 31653
  • Thanked: 5 times
  • "come fly with me"
    • View Profile
Jet Stream Joy !
« Reply #12 on: 01/10/2007 23:29:25 »
The monsoons influence the climates of India, Bangladesh, Southeast Asia,

and, to a lesser extent, northern Australia  and Central Africa.  For the most part, the

most prominent form of the monsoon climate is found on the Indian subcontinent.

There's a monsoon in my pants after I've had an Indian !!..forms it's own subcontinent too !!

Well I hope at least she was good!!!!

That should teach you to stop messing around with entities  that are just TOO hot for YOU TO HANDLE!! LOL You may find yourself on a continent a lonely old man!!!! LOL LOL..I couldn't resist....LOL
« Last Edit: 01/10/2007 23:31:14 by Karen W. »
 

The Naked Scientists Forum

Jet Stream Joy !
« Reply #12 on: 01/10/2007 23:29:25 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums