Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Jetstreams in southern hemisphere

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

Jetstreams in southern hemisphere

Thread Tools
 
Search this Thread
 
Old 25th Nov 2012, 19:39
  #1 (permalink)  
Thread Starter
 
Join Date: Mar 2010
Location: in a dirty cockpit
Posts: 431
Likes: 0
Received 0 Likes on 0 Posts
Jetstreams in southern hemisphere

Hi guys,

I have a question about Jetstreams in southern hemisphere.

We know that cyclone and anti-cyclone rotation, coriolis force etc. work in the opposite direction compared to the northern hemisphere; so why the jetstreams are westerly in both the hemispheres?

thank you

BTS
Breakthesilence is offline  
Old 25th Nov 2012, 20:42
  #2 (permalink)  
Per Ardua ad Astraeus
 
Join Date: Mar 2000
Location: UK
Posts: 18,579
Likes: 0
Received 0 Likes on 0 Posts
Simply because the 'coriolis force' reverses. If you sketch a cross-section of the 'polar fronts' (north and south hemisphere) and assuming you understand how a jet stream forms, you will see that the outflow of air from the 'tropical' airmass into the 'polar' will be deflected by the 'coriolis force'. If it did not reverse the jet streams would be easterly 'down under'.- QED?
BOAC is offline  
Old 25th Nov 2012, 21:02
  #3 (permalink)  
Thread Starter
 
Join Date: Mar 2010
Location: in a dirty cockpit
Posts: 431
Likes: 0
Received 0 Likes on 0 Posts
I just got the answer a minut ago while thinking about what you later said.

I made a reversion of the reversion

thanks!
Breakthesilence is offline  
Old 25th Nov 2012, 21:32
  #4 (permalink)  
Per Ardua ad Astraeus
 
Join Date: Mar 2000
Location: UK
Posts: 18,579
Likes: 0
Received 0 Likes on 0 Posts
I made a reversion of the reversion
- I'm not sure that is legal, even between consenting adults.........................
BOAC is offline  
Old 26th Nov 2012, 03:21
  #5 (permalink)  
Psychophysiological entity
 
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 84
Posts: 3,270
Received 37 Likes on 18 Posts
Baldrick didn't build your dirty flightdeck did he? But how else would you hop about in time?
Loose rivets is offline  
Old 26th Nov 2012, 09:48
  #6 (permalink)  
 
Join Date: Nov 2009
Location: in the mix muff
Age: 44
Posts: 176
Likes: 0
Received 0 Likes on 0 Posts
It all boils back to the Buy's Ballot therory:If you stand with your back to the wind in the southern hemisphere the cold air is to your right.During winter in the southern hemisphere in june-july,the warm air from the equator(hadley cells) rise and meet up the colder air from the southern hemisphere and this mixture of hot and cold air creates the jetstream effect we see at 20 degrees south
N1 Limit is offline  
Old 26th Nov 2012, 09:52
  #7 (permalink)  
Per Ardua ad Astraeus
 
Join Date: Mar 2000
Location: UK
Posts: 18,579
Likes: 0
Received 0 Likes on 0 Posts
Buy's Ballot theory (UK)
- if you stand with your back to the wind on the east coast the North Sea is on your left.
BOAC is offline  
Old 26th Nov 2012, 10:24
  #8 (permalink)  
 
Join Date: Jun 2004
Location: Surrounding the localizer
Posts: 2,200
Likes: 0
Received 2 Likes on 1 Post
Quote:
Buy's Ballot theory (UK)
If you can see the hills..it's going to rain..
If you can't see the hills it is raining..
If the water is rising..it's still raining..
If you stand with your back to the wind....it will get wet first...
haughtney1 is offline  
Old 26th Nov 2012, 16:06
  #9 (permalink)  
 
Join Date: Feb 2005
Location: flyover country USA
Age: 82
Posts: 4,579
Likes: 0
Received 0 Likes on 0 Posts
OK, now I understand that a hurricane (or other cyclonic phenom) originating in the Northern hemisphere cannot cross the equator.

But that cannot account for the fact that we here up North seem to never hear of hurricanes in Southern latitudes. Well, maybe the odd waterspout on the coast of Oz, ...

But might not the East coasts of Africa, SA, OZ etc. get hit with something like good ol' Uhmurruhcan hurricanes? Or are we the only ones so blessed?
barit1 is offline  
Old 27th Nov 2012, 00:56
  #10 (permalink)  
 
Join Date: Dec 1998
Location: Escapee from Ultima Thule
Posts: 4,273
Received 2 Likes on 2 Posts
That's because they're called 'cyclones' in Oz. Whether they're called cyclones, hurricanes or typhoons, they're all Tropical Revolving Storms.

Last edited by Tinstaafl; 27th Nov 2012 at 00:57.
Tinstaafl is offline  
Old 27th Nov 2012, 10:24
  #11 (permalink)  
 
Join Date: Jun 2011
Location: france
Posts: 760
Likes: 0
Received 0 Likes on 0 Posts
Snoop Eastside story

@BOAC
I counterfact your nice answer :
Originally Posted by BOAC
I'm not sure that is legal, even between consenting adults.........................
@Breakthesilence
Are you asking if the sun rises on the West side in the southern hemisphere ?!!!
Buys-Ballot and Coriolis are the result of earth rotation !
Please come back to reality, with the both feet in different shoes, look at the sky stars rotating during the night, an sun during the day.

roulishollandais
roulishollandais is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.