Lysis
User
Reged:
Posts: 451
Loc: Hong Kong
|
|
Hank… is that good science? The concept that there is some kind of global energy quota that is being fulfilled in our backyard? As always… not questioning you, just curious. It just sounds too poetic and simple to be true.
EDIT: Keith just pm'd me and sort of answered the question, so I am good.
--------------------
cheers
Edited by Lysis (Tue Jul 12 2005 05:38 PM)
|
Clark
Meteorologist
Reged:
Posts: 1710
Loc:
|
|
I'll go ahead and answer it here as well, for everyone's benefit.
Generally, the globe has an energy budget which must be maintained to keep the pole-to-equator temperature difference within reason. It's one of the many great things about this planet, really. One of the major means of doing this is transport from the tropics, where there is an energy "excess," to the midlatitudes & poles, where there is an energy "shortage."
Part of this transport is accomplished by oceanic transport, mid-latitude weather systems, and what we call the Hadley cell (a cross-Equatorial transport mechanism for all sorts of quantities, including energy); much of the rest comes from tropical cyclones. Tropical cyclones are a major source of energy and, upon entering the mid-latitudes, deposit that energy in one way or another -- outflow & convective heating aloft, wind and moisture from the storm itself, and so on. So, in essence, there is a balance that must be maintained...and tropical cyclones are one way about doing so.
I'm not going to comment about global TC activity and how it may relate to the activity here or the overall cycle, as it is something we tend to consider not in specifics but in more vague generalities.
--------------------
Current Tropical Model Output Plots
(or view them on the main page for any active Atlantic storms!)
|
Ryan
Storm Tracker
Reged:
Posts: 281
Loc: Long Island, NY / Stuart, FL
|
|
soon to be Franklin orr what?
Only time will tell, Ryan. --Clark
--------------------
2006 Atlantic Season Summary:
Bad, But Not AS Bad.
Life's a Storm, Watch Your Back
Edited by Clark (Tue Jul 12 2005 09:50 PM)
|
B.C.Francis
Storm Tracker
Reged:
Posts: 331
Loc: Indiatlantic Florida
|
|
And here we are, surface dwellers. We inhabit just about every known piece of rock that moves below us, and now our part of the world sees the limelight. The Cycles have been going on since the birth of our island earth. We just happen to be in the way......Weatherchef
|
Keith234
Storm Chaser
Reged:
Posts: 921
Loc: 40.7N/73.3W Long Island
|
|
Found an interesting link on the subject...
http://wxmaps.org/pix/hurpot.html
Apparently Dr. Emanuel developed an algorithm that figures out what you (Lysis) were talking about.
--------------------
"I became insane with horrible periods of sanity"
Edgar Allan Poe
|
Clark
Meteorologist
Reged:
Posts: 1710
Loc:
|
|
Keith -- that is what we call Maximum Potential Intensity, which isn't so much a manifestation of the global circulation, but one illustrating what we understand about the circulation of a tropical cyclone and the factors that impact its intensity. All that goes into it are temperatures at the ocean's surface and aloft (at the outflow layer) plus a bunch of other physical variables (drag coefficients and the like), allowing us to come up with a max. theoretical intensity of both wind speed and pressure.
This circulation assumes a Carnot cycle for the tropical storm -- too lengthy to explain here -- but needless to say, it is a direct circulation with inflow at low levels at about the temperature of the SST, rising motion near the center of the storm (slantwise moist ascent), moist outflow aloft, followed by moist and then dry descent at outer radii. It doesn't take into account the eye or the eyewall -- the features of which I've explained in a current post in the News Talkbacks -- but does a pretty good job of capturing the environmental factors affecting a single hurricane's intensity.
The global circulation deals more with the exchange of energy between the midlatitudes, polar regions, and tropics; some of these factors may work their way down to the fine-scale and impact SSTs and the like, but they aren't directly related.
--------------------
Current Tropical Model Output Plots
(or view them on the main page for any active Atlantic storms!)
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
