Correction
Locked
 
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Russell,
Of course you are correct.... the oceans reach max temperature three months after the max solar energy for your hemisphere. Does this imply that equitorial oceans are hottest in September AND June? Nick Nicholas S. Thompson Professor of Psychology and Ethology Clark University nickthompson at earthlink.net http://home.earthlink.net/~nickthompson/ nthompson at clarku.edu > [Original Message] > From: <Friam-request at redfish.com> > To: <Friam at redfish.com> > Date: 9/29/2005 7:52:30 PM > Subject: Friam Digest, Vol 27, Issue 33 > > Send Friam mailing list submissions to > Friam at redfish.com > > To subscribe or unsubscribe via the World Wide Web, visit > http://redfish.com/mailman/listinfo/friam_redfish.com > or, via email, send a message with subject or body 'help' to > Friam-request at redfish.com > > You can reach the person managing the list at > Friam-owner at redfish.com > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Friam digest..." > > > Today's Topics: > > 1. Re: Friam Digest, Vol 27, Issue 32 (Nicholas Thompson) > 2. Re: Friam Digest, Vol 27, Issue 32 (Russell Standish) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 29 Sep 2005 17:26:32 -0400 > From: "Nicholas Thompson" <nickthompson at earthlink.net> > Subject: Re: [FRIAM] Friam Digest, Vol 27, Issue 32 > To: Friam at redfish.com > Message-ID: <410-220059429212632480 at earthlink.net> > Content-Type: text/plain; charset=US-ASCII > > Thanks, Eric and Mike for such informative stuff, > > Please be careful with any information I may have been supplied. I am an > obsessive, not an expert. > > thanks, first off, for correcting my spelling of shear. Was I sellling > nylons? I dunno. > > I think the ocean flow you describe is correct. I remember reading > somewhere that it is the basis for the north atlantic oscillation, which > it stops, immediately occasons mile high glaciers in europe. > > I am sure you are right that the oceans are the key. The power of the > oceans to store heat is amazing. It is really true that the oceans are > warmest around sep 1 and coldest around jun 1. > > I do think we need a book. I have written already one informal book about > weather . Perhaps I will attempt another when I retire. > > All the best, > > Nick > > > > Nicholas S. Thompson > Professor of Psychology and Ethology > Clark University > nickthompson at earthlink.net > http://home.earthlink.net/~nickthompson/ > nthompson at clarku.edu > > > > [Original Message] > > From: <Friam-request at redfish.com> > > To: <Friam at redfish.com> > > Date: 9/29/2005 4:46:25 PM > > Subject: Friam Digest, Vol 27, Issue 32 > > > > Send Friam mailing list submissions to > > Friam at redfish.com > > > > To subscribe or unsubscribe via the World Wide Web, visit > > http://redfish.com/mailman/listinfo/friam_redfish.com > > or, via email, send a message with subject or body 'help' to > > Friam-request at redfish.com > > > > You can reach the person managing the list at > > Friam-owner at redfish.com > > > > When replying, please edit your Subject line so it is more specific > > than "Re: Contents of Friam digest..." > > > > > > Today's Topics: > > > > 1. Re: hurricanes (Nicholas Thompson) > > 2. Re: Friam Digest, Vol 27, Issue 31 (Mike Oliker) > > 3. shear, shear, and migration (Eric Smith) > > > > > > ---------------------------------------------------------------------- > > > > Message: 1 > > Date: Thu, 29 Sep 2005 14:55:24 -0400 > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > Subject: Re: [FRIAM] hurricanes > > To: Friam at redfish.com > > Cc: adhocsys <adhocsys at comcast.net> > > Message-ID: <410-220059429185524918 at earthlink.net> > > Content-Type: text/plain; charset=US-ASCII > > > > All > > > > I continue to be puzzled by the following paradox > > > > Hurricanes are made of thunderstorms > > Thunderstorms require sheer > > The parts of hurricanes most prone to tornados are subject to sheer > > Hurricanes are destroyed by sheer. > > > > It seems that perhaps the way out of that paradox is to say that a > > hurricane is some sort of coherent system for provideing sheer to > > thunderstorms which ITSELF is sensative to sheer. So a hurricane is > itself > > a sort of sheer providing system. Then I began to wonder if perhaps the > > sheer might be negative sheer. Think of spiral columns of thunderstorms > > moving rapidly toward the center of the hurricane in a situation in > > the air OVER the thunderstorms is not moving so fast or even spiraling in > > the opposte direction. Then it would be the movement of the thunderstorms > > themselves, dictated by the structure of the hurricane itself, that > > produces the sheer. So, to reiterate, the idea is: in normal strong > > thunderstorms, the sheer is provided by jetstreams over the thundrstorm, > > high level currents that more more rapidly than the storm it self (in some > > direction or other ) . In a hurricane, the sheer is provided by > > rapidlymoving thundrstorms moving under a realtively static (or contrarily > > rotating) upper level atmosphere? > > > > Ring any bells with anybody? > > > > I agree with Eric that we need a book! > > > > Nick > > > > Nicholas S. Thompson > > Professor of Psychology and Ethology > > Clark University > > nickthompson at earthlink.net > > http://home.earthlink.net/~nickthompson/ > > nthompson at clarku.edu > > > > > > > [Original Message] > > > From: <Friam-request at redfish.com> > > > To: <Friam at redfish.com> > > > Date: 9/29/2005 12:00:45 PM > > > Subject: Friam Digest, Vol 27, Issue 31 > > > > > > Send Friam mailing list submissions to > > > Friam at redfish.com > > > > > > To subscribe or unsubscribe via the World Wide Web, visit > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > or, via email, send a message with subject or body 'help' to > > > Friam-request at redfish.com > > > > > > You can reach the person managing the list at > > > Friam-owner at redfish.com > > > > > > When replying, please edit your Subject line so it is more specific > > > than "Re: Contents of Friam digest..." > > > > > > > > > Today's Topics: > > > > > > 1. Hurricanes (Nicholas Thompson) > > > > > > > > > ---------------------------------------------------------------------- > > > > > > Message: 1 > > > Date: Wed, 28 Sep 2005 20:26:57 -0600 > > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > > Subject: [FRIAM] Hurricanes > > > To: Friam at redfish.com > > > Message-ID: <410-22005942922657409 at earthlink.net> > > > Content-Type: text/plain; charset=US-ASCII > > > > > > thank you, Eric, Robert, and Mike for these wonderful posts. I want > > > consider each in detail, but in the meantime, a few random thoughts. > > > > > > (1) I understand the movement of heat from low latituds to high > lattitudes > > > as a "function" of hurricanes but am less certain about the vertical > > > assymetry in temperature. A stable atmosphere is three to five degrees > F > > > -- average --- cooler for every thousand feet of altitude up to the > > > tropopause ... somewhere around 35kfeet or so. . So, for instance, in > an > > > atmosphere that is, say 80 degrees at the surface is symmetrical if the > > > temperature is, say, zero F at 20 kfeet. (Dont hold me to the exact > > > numbers.) So if temperature cannot be the name of the property of an > > > atmosphere that is UNstable. Are we talking about relative temperature, > > > the lifted index..... what IS that property. Is latent heat the sort > of > > > thing there can be an assymetry in? > > > > > > (2) Having read hundreds of hurricane discussions in the last year > > > assiduously -- some would say obsessively --, I dont get the impression > > > that hurricanes are "trying" to go north. They just go wherever the > wind > > > blows them. The currents that move them along are miniscule compared to > > > the currents within the storm, which is why I asked if a hurricane is > more > > > like a top, a whirlpool, or a dervish. Hurricanes start where it is > warm > > > and are dirrected by the currents that move along the bottom of a > > > subtropical high. When they hit the west end of the high they turn > > north. > > > The reason they appear to be a north-going thing is that they start in > the > > > south and if they get north they die. but they can as easiy be > > > south if they get into a south moving current. over water that is warm > > > enough to sustain them. Every rare once in a while, when the bermuda > > high > > > pressed low enough a hurrican (or tropical storm) will come up the coast > > of > > > the US, turn eastward over the atlantic, travel back toward africa, and > > > then head south around the EASTERN end of the Bermuda High. The > Bermuda > > > High is itself a mixer but so far as the high is concerned, if a > hurrican > > > wants to walk around the top of it to africa, it is happy to comply. > > > > > > (3) Finally, I wonder if anybody could help with the intuition block > that > > > makes it difficult for me to think of a whirling column of air as an > > > obstacle. I can see how it might suck me in but I cannot see how it > might > > > bounce me off. > > > > > > Nick > > > > > > Nicholas S. Thompson > > > Professor of Psychology and Ethology > > > Clark University > > > nickthompson at earthlink.net > > > http://home.earthlink.net/~nickthompson/ > > > nthompson at clarku.edu > > > > > > > > > > [Original Message] > > > > From: <Friam-request at redfish.com> > > > > To: <Friam at redfish.com> > > > > Date: 9/28/2005 6:36:18 PM > > > > Subject: Friam Digest, Vol 27, Issue 30 > > > > > > > > Send Friam mailing list submissions to > > > > Friam at redfish.com > > > > > > > > To subscribe or unsubscribe via the World Wide Web, visit > > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > or, via email, send a message with subject or body 'help' to > > > > Friam-request at redfish.com > > > > > > > > You can reach the person managing the list at > > > > Friam-owner at redfish.com > > > > > > > > When replying, please edit your Subject line so it is more specific > > > > than "Re: Contents of Friam digest..." > > > > > > > > > > > > Today's Topics: > > > > > > > > 1. Fwd: YOUR E-MAIL ADDRESS WON THE LOTTERY. (Owen Densmore) > > > > 2. Hurricanes and engines (Eric Smith) > > > > 3. Re: Fwd: YOUR E-MAIL ADDRESS WON THE LOTTERY. (Russell > > > > 4. Hurricanes, People and Turbulence (Mike Oliker) > > > > 5. Re: What are Hurricanes? (Robert Cordingley) > > > > > > > > > > > > - > > > > Hi Nick and all, > > > > > > > > Figured all lurk and no pay makes Eric a parasite. > > > > > > > > I think Steve is very right about the engine interpretation, and > > > > offer a few details to it. I haven't done the math for this, but > > > > suspect I can correctly guess qualitative features. > > > > > > > > A secondary point of quantification: SFI had a visitor from NOAA about > > > > a year ago (I forget her name; she was interested in medium-range > > > > weather forecasting and how well it stood up under onset of chaotic > > > > dynamics) who told me that the existence of the cyclonic storm seasons > > > > raises the polar temeratures by about 3 degrees in early winter > > > > relative to what it would be without them. So Steve is right about > > > > transport of heat from bottom to top of the atmosphere, but one should > > > > also appreciate the importance of equator-to-pole transport. I > > > > suspect this is part of the reason for the tropic-to-temperate paths > > > > taken by storms in the Atlantic (haven't ever looked at pacific > > > > storms to see if they do the same thing). > > > > > > > > Second point to appreciate is the extreme importance of water in > > > > distinguishing hurricanes, and this adds to Steve's point, and changes > > > > it perhaps a bit. It is not just transport of heat from lower to > > > > upper atmosphere. The thing hurricanes do systematically is draw in > > > > cool, relatively dry air from mid to upper atmosphere hundreds of > > > > miles away, dragging it over the ocean where it can absorb warm water > > > > which is then convected upward. The water carries ocean heat into the > > > > atmosphere through the specific heat of vaporization, I suspect in far > > > > larger degree than through any temperature change. As the convected > > > > water vapor reaches the upper atmosphere it condenses, releasing the > > > > latent heat to the air where it can be radiated off to space, and > > > > releasing the now-cooled water to fall as rain, some of which > > > > re-evaporates on the way down but much of which falls back into the > > > > ocean whence it came, replacing the warm water with cold. The air > > > > transported up in the convective column flows out in dehydrated form > > > > at high atmospheric levels, to replace the air drawn in at the base of > > > > the system to sweep over the ocean. > > > > > > > > My guess is that if one compared hurricane convection to disordered > > > > Benard convection or thunderstorm systems covering the same area, one > > > > would find that the hurricane cycles a vastly greater volume of > > > > atmosphere laterally across the ocean surface, and with that cycles a > > > > vastly greater volume of ocean water through the > > > > evaporation/condensation cycle, and that through that mechanism it > > > > transports more heat both vertically, and up-lattitude as a > > > > second-order effect, than disordered storms could. The extent to > > > > which it seems relevant to recognize that as a function is the extent > > > > to which the function, particularly, is relief of a thermal stress. > > > > The large-scale relief of stress seems to be the "force" (to use a > > > > word badly) that favors the emergence and stabilization of > > > > nonequilibrium channels through which the stress is relieved. > > > > > > > > Regarding "individuality" at the level of named storms: It is > > > > interesting that, if we regard the reliability of hurricane form as > > > > empirical evidence, the most efficient such engine the atmosphere > > > > finds is one in which the tens of thousands of square miles of shear > > > > flow are subordinated to the angularly ordered convective system, > > > > notable near the eyewall. In that sense each storm creates conditions > > > > that essentially preclude the concurrent formation of other eyewall > > > > systems in proximity competing for (or driven into existence by) the > > > > same sources of energy. The exception, of course, being the eyewall > > > > replacement, in which the instability of extreme angular momenta > > > > around a very small eye apparently weaken its ability to constrain all > > > > the surrounding lateral convection, and the conditions that led to the > > > > original eyewall do lead to the formation of a new secondary eyewall > > > > concentric with the destabilizing one that is on the way out. > > > > > > > > I would readily identify this regularity of form with the regularity > > > > of form of the chemistry in lightning strikes, and probably with the > > > > regularity of form of certain biochemical pathways. The individual > > > > who emerges in biology, however, probably does so in response to > > > > rather different sequences of pressures, even though once emerged, he > > > > shares certain "Darwinian" aspects with the individual hurricane. > > > > > > > > I have thought for years it would be wonderful to see a book in which > > > > a comprehensive suite of mathematical models of hurricanes was > > > > reviewed, from abstract to quantitatively accurate. If anybody knows > > > > of a compact and well-written book, I would enjoy reading it. > > > > > > > > Eric > > > > > > > > > > > > > > > > > > > > > > > > ------------------------------ > > > > > > > > ------------------------------ > > > > > > > > Message: 4 > > > > Date: Wed, 28 Sep 2005 18:08:32 -0600 > > > > From: "Mike Oliker" <mike.oliker at comcast.net> > > > > Subject: [FRIAM] Hurricanes, People and Turbulence > > > > To: <Friam at redfish.com> > > > > Message-ID: <012701c5c489$f10cd1c0$0300a8c0 at INSPIRON2650> > > > > Content-Type: text/plain; charset="us-ascii" > > > > > > > > Robert's response reminds me of the questions I started the semester > > with > > > > when I taught Chaos, Fractals, and Complexity to Honors Undergrads > > UNM: > > > > (1) What is a Forest that isn't trees? > > > > (2) What is a Person that isn't cells? > > > > > > > > Also, about the Hurricanes thread: > > > > Is turbulence alive? Looking at a Von Karmen Vortex street > > > > > > > > > > > > > > enStreet2.gif) one sees > > > > a sequence of vortices shed as air goes past an obstruction. I would > > > argue > > > > that each vortex as is shed it creates the perturbation which assures > > that > > > > the next vortex will match it in mirror image. Thus, it is > reproducing. > > > > There is an initial period as the air is starting up, where a great > > > > diversity of turbules (bits of spinning air) arises but these quickly > > > evolve > > > > into a single species (until the wind changes). These vortices are > > > throwing > > > > up spontaneous obsticles to the air flow which allows them to gather > > > energy > > > > from the flowing wind -- in Stu Kauffman terms they are harnessing a > > > > thermodynamic work cycle, harvesting energy from their environment. > > > > > > > > Hurricanes are quite similar. They gather vastly more energy by > > > > facilitating the flow of heat from the warm ocean to the cool high > > > altitude > > > > air. They exist in a more diverse environment with many other air > flow > > > > species. Where turbulence resolves it's symmetry breaking early and > > only > > > > once, hurricanes must do so over and over. They are less effective > > (thank > > > > God) at reproduction. > > > > > > > > By the way, if galaxies are like hurricanes and turbulence is alive > ... > > > > > > > > -Mike Oliker > > > > > > > > > > > > > > > > Message: 1 > > > > Date: Tue, 27 Sep 2005 09:26:49 -0600 > > > > From: Robert Holmes <rholmes62 at gmail.com> > > > > Subject: Re: [FRIAM] What are Hurricanes? > > > > To: The Friday Morning Applied Complexity Coffee Group > > > > <Friam at redfish.com> > > > > Message-ID: <8577701505092708263b0f4bd5 at mail.gmail.com> > > > > Content-Type: text/plain; charset=ISO-8859-1 > > > > > > > > On 9/27/05, Jochen Fromm <fromm at vs.uni-kassel.de> wrote: > > > > > > > > > > ... Nevertheless, I > > > > > think it is interesting that hurricanes get names, although they > > > > > non-permanent, volatile and temporary dynamic phenomena. .... > > > > > > > > Just like humans :) > > > > > > > > > > > > -------------- next part -------------- > > > > An HTML attachment was scrubbed... > > > > URL: > > > > > > > > > /attachment-0001.htm > > > > > > > > ------------------------------ > > > > > > > > Message: 5 > > > > Date: Wed, 28 Sep 2005 19:34:45 -0500 > > > > From: Robert Cordingley <robert at cirrillian.com> > > > > Subject: Re: [FRIAM] What are Hurricanes? > > > > To: The Friday Morning Applied Complexity Coffee Group > > > > <Friam at redfish.com> > > > > Message-ID: <433B36A5.5070501 at cirrillian.com> > > > > Content-Type: text/plain; charset="us-ascii" > > > > > > > > There was an interesting article in the NY Science Times: > > > > > > > > http://www.nytimes.com/2005/09/27/science/earth/27loop.html > > > > > > > > which you might be able to see. The article discusses the dimension > of > > > > subsea energy and the depth of warm water needed. So it also > > on > > > > subsea counterpart(s) - the loop - and other 'things' which should be > > > > considered as the storm makes it's way across our oceans? > > > > > > > > Robert Cordingley > > > > > > > > > > > > Douglas Roberts wrote: > > > > > > > > > Not to mention; full of hot air. > > > > > > > > > > On 9/27/05, Robert Holmes <rholmes62 at gmail.com > > > > > <mailto:rholmes62 at gmail.com>> wrote: > > > > > > > > > > On 9/27/05, Jochen Fromm <fromm at vs.uni-kassel.de > > > > > <mailto:fromm at vs.uni-kassel.de>> wrote: > > > > > > > > > > > > ... Nevertheless, I > > > > > > think it is interesting that hurricanes get names, although > > > > > > they are non-permanent, volatile and temporary dynamic > > phenomena. > > > > > > .... > > > > > > > > > > Just like humans :) > > > > > > > > > > <snipped> > > > > > > > > > -------------- next part -------------- > > > > An HTML attachment was scrubbed... > > > > URL: > > > > > > > > > /attachment.htm > > > > > > > > ------------------------------ > > > > > > > > _______________________________________________ > > > > Friam mailing list > > > > Friam at redfish.com > > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > > > > > > > End of Friam Digest, Vol 27, Issue 30 > > > > ************************************* > > > > > > > > > > > > > > > > > > ------------------------------ > > > > > > _______________________________________________ > > > Friam mailing list > > > Friam at redfish.com > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > > > > End of Friam Digest, Vol 27, Issue 31 > > > ************************************* > > > > > > > > > > > > ------------------------------ > > > > Message: 2 > > Date: Thu, 29 Sep 2005 13:17:06 -0600 > > From: "Mike Oliker" <mike.oliker at comcast.net> > > Subject: Re: [FRIAM] Friam Digest, Vol 27, Issue 31 > > To: <Friam at redfish.com> > > Message-ID: <014001c5c52a$64a217d0$0300a8c0 at INSPIRON2650> > > Content-Type: text/plain; charset="us-ascii" > > > > Nick, > > > > (1) The atmosphere is in a high energy state (cool DENSE air on the top, > > warm THIN air on the bottom, if they can switch places they shift to a > much > > lower energy state, but where to break symmetry? Buoyancy drives the > > system. Humidity comes in to it by keeping the warm air warm much > > than sensible heat alone can do. > > > > (3) If two fluid streams collide, they can either deflect around one > > another, or undergo mixing. Mixing will only occur if there are strong > > shears with sharp velocity gradients to mix the streams turbulently. By > > deflecting when possible, the streams keep the shear forces down, the > > gradients small, and easily preserve their angular and linear momentum. > It > > is the path of least resistance. So, in the free air, they will be > > deflected mostly, and act as though their boundaries were obstacles. > > > > -MikeO > > > > -----Original Message----- > > Message: 1 > > Date: Wed, 28 Sep 2005 20:26:57 -0600 > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > Subject: [FRIAM] Hurricanes > > To: Friam at redfish.com > > Message-ID: <410-22005942922657409 at earthlink.net> > > Content-Type: text/plain; charset=US-ASCII > > > > thank you, Eric, Robert, and Mike for these wonderful posts. I want to > > consider each in detail, but in the meantime, a few random thoughts. > > > > (1) I understand the movement of heat from low latituds to high > > as a "function" of hurricanes but am less certain about the vertical > > assymetry in temperature. A stable atmosphere is three to five degrees F > > -- average --- cooler for every thousand feet of altitude up to the > > tropopause ... somewhere around 35kfeet or so. . So, for instance, in an > > atmosphere that is, say 80 degrees at the surface is symmetrical if the > > temperature is, say, zero F at 20 kfeet. (Dont hold me to the exact > > numbers.) So if temperature cannot be the name of the property of an > > atmosphere that is UNstable. Are we talking about relative temperature, > > the lifted index..... what IS that property. Is latent heat the sort of > > thing there can be an assymetry in? > > > > (2) Having read hundreds of hurricane discussions in the last year > > assiduously -- some would say obsessively --, I dont get the impression > that > > hurricanes are "trying" to go north. They just go wherever the wind blows > > them. The currents that move them along are miniscule compared to the > > currents within the storm, which is why I asked if a hurricane is more > like > > a top, a whirlpool, or a dervish. Hurricanes start where it is warm and > are > > dirrected by the currents that move along the bottom of a subtropical > high. > > When they hit the west end of the high they turn north. > > The reason they appear to be a north-going thing is that they start in the > > south and if they get north they die. but they can as easiy be carried > > south if they get into a south moving current. over water that is warm > > enough to sustain them. Every rare once in a while, when the bermuda > high > > pressed low enough a hurrican (or tropical storm) will come up the coast > of > > the US, turn eastward over the atlantic, travel back toward africa, and > > then head south around the EASTERN end of the Bermuda High. The Bermuda > > High is itself a mixer but so far as the high is concerned, if a hurrican > > wants to walk around the top of it to africa, it is happy to comply. > > > > (3) Finally, I wonder if anybody could help with the intuition block that > > makes it difficult for me to think of a whirling column of air as an > > obstacle. I can see how it might suck me in but I cannot see how it might > > bounce me off. > > > > Nick > > > > Nicholas S. Thompson > > Professor of Psychology and Ethology > > Clark University > > nickthompson at earthlink.net <http://home.earthlink.net/~nickthompson/> > > http://home.earthlink.net/~nickthompson/ > > nthompson at clarku.edu > > > > > > -------------- next part -------------- > > An HTML attachment was scrubbed... > > URL: > > /attachment-0001.htm > > > > ------------------------------ > > > > Message: 3 > > Date: Thu, 29 Sep 2005 14:46:38 -0600 (MDT) > > From: "Eric Smith" <desmith at santafe.edu> > > Subject: [FRIAM] shear, shear, and migration > > To: Friam at redfish.com > > Message-ID: <200509292046.j8TKkKGI016017 at kakapo.santafe.edu> > > Content-Type: text/plain; charset=US-ASCII > > > > Hi Nick, > > > > Unfortunately, given that I find them interesting, the amount I don't > > know about Hurricanes fills volumes. On the other hand, I think you > > are a victim of language, created because weather people, like > > everyone else, never speak in complete sentences. > > > > So first, to shear and Shear. Scale matters here. A Hurricane is a > > structure of shear flows. Unless I am terribly missing the point, > > that is why it spins, why the eyewall has the structure it does, etc. > > Shear is what makes the coriolis force matter. A net influx of air > > toward the eye (shear over the ocean) at low level causes > > more-equatorial air to move northward and more-polar air southward. > > Because they keep some of their angular momentum, the more-equatorial > > air has a net eastward velocity relative to the more-polar component. > > This angular momentum conservation creates the vortex, and the fact > > that the low pressure in the central regions is only capable of > > supporting a limited centripetal force causes the influx to stop at a > > nonzero radius, leaving the eye. I think that this is why wind speed > > in the storm is directly related to (and caused by) the pressure > > reduction in the eye (there is also some Bernoulli relation relating > > pressure and velocity in the eyewall with pressure and stillness in > > the eye, which would provide a different-looking equation to arrive at > > the same result). > > > > Some of the angular momentum is not convected, because the air has > > friction, so the total angular momentum at the top of the convection > > system, where it must flow back out (shear at high altituted) is not > > what it brought in with it. Hence there is a negative velocity of the > > more-equatorial air near the eye now going back toward the equator, > > and the more-polar air near the eye going back toward the pole. So we > > get spiral flow at the top in the antisense of the flow at the > > bottom. All this is shear, but it is shear at the scale of the > > substructure of the storm itself, rather than net Shear at the scale > > of the whole atmosphere. > > > > I assume, though I can't back it up, that the form of shear weathermen > > speak of as disruptive of hurricanes, is Shear on the scale of the > > whole atmosphere, which is transporting and dissipating angular > > momentum in lattitude in other ways than those that form a clean > > vortex. Think of stirring the water going down the drain, and how > > that can inhibit the formation of a drain vortex. That is a > > disruptive Shear phenomenon, but the vortex itself, when it forms, is > > also a shear phenomenon. > > > > Re polar migration. Thank you for providing a lot of detail I didn't > > know about that. Perhaps I should have been thinking of the oceans as > > the place to look for the original polar motion, though that seems too > > limited. I thought that the gulf stream runs northward near the > > surface, warming England and Scotland, but where it gives that heat up > > to the atmosphere, the water cools and dives, returning to the equator > > in the deep mid-atlantic, where it eventually wells up, is reheated by > > the sun, and meanders (via loop currents or however) back northward. > > If that is correct, then what you say about Hurricanes following ocean > > tracks would be consistent with northward tendencies, because the > > ocean currents go north at the surface to be cooled. (Please pardon > > the intentional language here. They do what they do because they > > solve differential equations, where sinking leaves a low pressure that > > draws in warm surface water, etc. It is easier to assume we all know > > there is some such mechanics behind it and encode that in saying "to > > be cooled".) I still tend to expect that, with all sorts of > > variations and stochasticity, there is a larger principle here that > > governs atmosphere and oceans through whatever coordinated currents: > > that heat is delivered mostly in the equator and tropics, and > > dissipates as uniformly as it can (meaning, limited by the degree to > > which temperature can be equalized) over the globe. Thus net > > transport of heat from equator and tropics to poles is the background > > leading to all the various currents. There is a lot more heat in the > > oceans than atmosphere, in addition to which that is where most of > > the sunlight is actually absorbed and converted to heat. So it would > > be reasonable that the oceans are the big engine, and the atmosphere > > follows along. > > > > Anyway, all most interesting... > > > > Eric > > > > > > > > > > > > > > > > > > ------------------------------ > > > > _______________________________________________ > > Friam mailing list > > Friam at redfish.com > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > End of Friam Digest, Vol 27, Issue 32 > > ************************************* > > > > > > ------------------------------ > > Message: 2 > Date: Fri, 30 Sep 2005 08:20:56 +1000 > From: Russell Standish <r.standish at unsw.edu.au> > Subject: Re: [FRIAM] Friam Digest, Vol 27, Issue 32 > To: nickthompson at earthlink.net, The Friday Morning Applied Complexity > Coffee Group <Friam at redfish.com> > Message-ID: <20050929222056.GA1016 at mpi.NSW.bigpond.net.au> > Content-Type: text/plain; charset=us-ascii > > On Thu, Sep 29, 2005 at 05:26:32PM -0400, Nicholas Thompson wrote: > > > > I am sure you are right that the oceans are the key. The power of the > > oceans to store heat is amazing. It is really true that the oceans are > > warmest around sep 1 and coldest around jun 1. > > > > Northern hemisphere perhaps. I was swimming in the oceans around here > during June, and the water temp was lovely. On the other hand I went > for a brief dip a couple of weekends ago, and it was rather chilly. I > don't expect it to really warm up until mid-December. > > Cheers > > -- > *PS: A number of people ask me about the attachment to my email, which > is of type "application/pgp-signature". Don't worry, it is not a > virus. It is an electronic signature, that may be used to verify this > email came from me if you have PGP or GPG installed. Otherwise, you > may safely ignore this attachment. > > > A/Prof Russell Standish Phone 8308 3119 (mobile) > Mathematics 0425 253119 (") > UNSW SYDNEY 2052 R.Standish at unsw.edu.au > Australia http://parallel.hpc.unsw.edu.au/rks > International prefix +612, Interstate prefix 02 > ---------------------------------------------------------------------------- > > > > ------------------------------ > > _______________________________________________ > Friam mailing list > Friam at redfish.com > http://redfish.com/mailman/listinfo/friam_redfish.com > > > End of Friam Digest, Vol 27, Issue 33 > ************************************* |
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I think so - the few times I've swum in equatorial waters (in
Indonesia) it seemed pleasant, almost bathlike temperatures. I don't think the ocean temperature there varies much through the year. Cheers On Thu, Sep 29, 2005 at 10:46:25PM -0400, Nicholas Thompson wrote: > Russell, > > Of course you are correct.... > > the oceans reach max temperature three months after the max solar energy > for your hemisphere. > Does this imply that equitorial oceans are hottest in September AND June? > > Nick > > Nicholas S. Thompson > Professor of Psychology and Ethology > Clark University > nickthompson at earthlink.net > http://home.earthlink.net/~nickthompson/ > nthompson at clarku.edu > > > > [Original Message] > > From: <Friam-request at redfish.com> > > To: <Friam at redfish.com> > > Date: 9/29/2005 7:52:30 PM > > Subject: Friam Digest, Vol 27, Issue 33 > > > > Send Friam mailing list submissions to > > Friam at redfish.com > > > > To subscribe or unsubscribe via the World Wide Web, visit > > http://redfish.com/mailman/listinfo/friam_redfish.com > > or, via email, send a message with subject or body 'help' to > > Friam-request at redfish.com > > > > You can reach the person managing the list at > > Friam-owner at redfish.com > > > > When replying, please edit your Subject line so it is more specific > > than "Re: Contents of Friam digest..." > > > > > > Today's Topics: > > > > 1. Re: Friam Digest, Vol 27, Issue 32 (Nicholas Thompson) > > 2. Re: Friam Digest, Vol 27, Issue 32 (Russell Standish) > > > > > > ---------------------------------------------------------------------- > > > > Message: 1 > > Date: Thu, 29 Sep 2005 17:26:32 -0400 > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > Subject: Re: [FRIAM] Friam Digest, Vol 27, Issue 32 > > To: Friam at redfish.com > > Message-ID: <410-220059429212632480 at earthlink.net> > > Content-Type: text/plain; charset=US-ASCII > > > > Thanks, Eric and Mike for such informative stuff, > > > > Please be careful with any information I may have been supplied. I am an > > obsessive, not an expert. > > > > thanks, first off, for correcting my spelling of shear. Was I sellling > > nylons? I dunno. > > > > I think the ocean flow you describe is correct. I remember reading > > somewhere that it is the basis for the north atlantic oscillation, which > if > > it stops, immediately occasons mile high glaciers in europe. > > > > I am sure you are right that the oceans are the key. The power of the > > oceans to store heat is amazing. It is really true that the oceans are > > warmest around sep 1 and coldest around jun 1. > > > > I do think we need a book. I have written already one informal book about > > weather . Perhaps I will attempt another when I retire. > > > > All the best, > > > > Nick > > > > > > > > Nicholas S. Thompson > > Professor of Psychology and Ethology > > Clark University > > nickthompson at earthlink.net > > http://home.earthlink.net/~nickthompson/ > > nthompson at clarku.edu > > > > > > > [Original Message] > > > From: <Friam-request at redfish.com> > > > To: <Friam at redfish.com> > > > Date: 9/29/2005 4:46:25 PM > > > Subject: Friam Digest, Vol 27, Issue 32 > > > > > > Send Friam mailing list submissions to > > > Friam at redfish.com > > > > > > To subscribe or unsubscribe via the World Wide Web, visit > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > or, via email, send a message with subject or body 'help' to > > > Friam-request at redfish.com > > > > > > You can reach the person managing the list at > > > Friam-owner at redfish.com > > > > > > When replying, please edit your Subject line so it is more specific > > > than "Re: Contents of Friam digest..." > > > > > > > > > Today's Topics: > > > > > > 1. Re: hurricanes (Nicholas Thompson) > > > 2. Re: Friam Digest, Vol 27, Issue 31 (Mike Oliker) > > > 3. shear, shear, and migration (Eric Smith) > > > > > > > > > ---------------------------------------------------------------------- > > > > > > Message: 1 > > > Date: Thu, 29 Sep 2005 14:55:24 -0400 > > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > > Subject: Re: [FRIAM] hurricanes > > > To: Friam at redfish.com > > > Cc: adhocsys <adhocsys at comcast.net> > > > Message-ID: <410-220059429185524918 at earthlink.net> > > > Content-Type: text/plain; charset=US-ASCII > > > > > > All > > > > > > I continue to be puzzled by the following paradox > > > > > > Hurricanes are made of thunderstorms > > > Thunderstorms require sheer > > > The parts of hurricanes most prone to tornados are subject to sheer > > > Hurricanes are destroyed by sheer. > > > > > > It seems that perhaps the way out of that paradox is to say that a > > > hurricane is some sort of coherent system for provideing sheer to > > > thunderstorms which ITSELF is sensative to sheer. So a hurricane is > > itself > > > a sort of sheer providing system. Then I began to wonder if perhaps the > > > sheer might be negative sheer. Think of spiral columns of thunderstorms > > > moving rapidly toward the center of the hurricane in a situation in > which > > > the air OVER the thunderstorms is not moving so fast or even spiraling > in > > > the opposte direction. Then it would be the movement of the > thunderstorms > > > themselves, dictated by the structure of the hurricane itself, that > > > produces the sheer. So, to reiterate, the idea is: in normal strong > > > thunderstorms, the sheer is provided by jetstreams over the thundrstorm, > > > high level currents that more more rapidly than the storm it self (in > some > > > direction or other ) . In a hurricane, the sheer is provided by > > > rapidlymoving thundrstorms moving under a realtively static (or > contrarily > > > rotating) upper level atmosphere? > > > > > > Ring any bells with anybody? > > > > > > I agree with Eric that we need a book! > > > > > > Nick > > > > > > Nicholas S. Thompson > > > Professor of Psychology and Ethology > > > Clark University > > > nickthompson at earthlink.net > > > http://home.earthlink.net/~nickthompson/ > > > nthompson at clarku.edu > > > > > > > > > > [Original Message] > > > > From: <Friam-request at redfish.com> > > > > To: <Friam at redfish.com> > > > > Date: 9/29/2005 12:00:45 PM > > > > Subject: Friam Digest, Vol 27, Issue 31 > > > > > > > > Send Friam mailing list submissions to > > > > Friam at redfish.com > > > > > > > > To subscribe or unsubscribe via the World Wide Web, visit > > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > or, via email, send a message with subject or body 'help' to > > > > Friam-request at redfish.com > > > > > > > > You can reach the person managing the list at > > > > Friam-owner at redfish.com > > > > > > > > When replying, please edit your Subject line so it is more specific > > > > than "Re: Contents of Friam digest..." > > > > > > > > > > > > Today's Topics: > > > > > > > > 1. Hurricanes (Nicholas Thompson) > > > > > > > > > > > > ---------------------------------------------------------------------- > > > > > > > > Message: 1 > > > > Date: Wed, 28 Sep 2005 20:26:57 -0600 > > > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > > > Subject: [FRIAM] Hurricanes > > > > To: Friam at redfish.com > > > > Message-ID: <410-22005942922657409 at earthlink.net> > > > > Content-Type: text/plain; charset=US-ASCII > > > > > > > > thank you, Eric, Robert, and Mike for these wonderful posts. I want > to > > > > consider each in detail, but in the meantime, a few random thoughts. > > > > > > > > (1) I understand the movement of heat from low latituds to high > > lattitudes > > > > as a "function" of hurricanes but am less certain about the vertical > > > > assymetry in temperature. A stable atmosphere is three to five > degrees > > F > > > > -- average --- cooler for every thousand feet of altitude up to the > > > > tropopause ... somewhere around 35kfeet or so. . So, for instance, > in > > an > > > > atmosphere that is, say 80 degrees at the surface is symmetrical if > the > > > > temperature is, say, zero F at 20 kfeet. (Dont hold me to the exact > > > > numbers.) So if temperature cannot be the name of the property of an > > > > atmosphere that is UNstable. Are we talking about relative > temperature, > > > > the lifted index..... what IS that property. Is latent heat the sort > > of > > > > thing there can be an assymetry in? > > > > > > > > (2) Having read hundreds of hurricane discussions in the last year > > > > assiduously -- some would say obsessively --, I dont get the > impression > > > > that hurricanes are "trying" to go north. They just go wherever the > > wind > > > > blows them. The currents that move them along are miniscule compared > to > > > > the currents within the storm, which is why I asked if a hurricane is > > more > > > > like a top, a whirlpool, or a dervish. Hurricanes start where it is > > warm > > > > and are dirrected by the currents that move along the bottom of a > > > > subtropical high. When they hit the west end of the high they turn > > > north. > > > > The reason they appear to be a north-going thing is that they start in > > the > > > > south and if they get north they die. but they can as easiy be > carried > > > > south if they get into a south moving current. over water that is warm > > > > enough to sustain them. Every rare once in a while, when the bermuda > > > high > > > > pressed low enough a hurrican (or tropical storm) will come up the > coast > > > of > > > > the US, turn eastward over the atlantic, travel back toward africa, > and > > > > then head south around the EASTERN end of the Bermuda High. The > > Bermuda > > > > High is itself a mixer but so far as the high is concerned, if a > > hurrican > > > > wants to walk around the top of it to africa, it is happy to comply. > > > > > > > > (3) Finally, I wonder if anybody could help with the intuition block > > that > > > > makes it difficult for me to think of a whirling column of air as an > > > > obstacle. I can see how it might suck me in but I cannot see how it > > might > > > > bounce me off. > > > > > > > > Nick > > > > > > > > Nicholas S. Thompson > > > > Professor of Psychology and Ethology > > > > Clark University > > > > nickthompson at earthlink.net > > > > http://home.earthlink.net/~nickthompson/ > > > > nthompson at clarku.edu > > > > > > > > > > > > > [Original Message] > > > > > From: <Friam-request at redfish.com> > > > > > To: <Friam at redfish.com> > > > > > Date: 9/28/2005 6:36:18 PM > > > > > Subject: Friam Digest, Vol 27, Issue 30 > > > > > > > > > > Send Friam mailing list submissions to > > > > > Friam at redfish.com > > > > > > > > > > To subscribe or unsubscribe via the World Wide Web, visit > > > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > or, via email, send a message with subject or body 'help' to > > > > > Friam-request at redfish.com > > > > > > > > > > You can reach the person managing the list at > > > > > Friam-owner at redfish.com > > > > > > > > > > When replying, please edit your Subject line so it is more specific > > > > > than "Re: Contents of Friam digest..." > > > > > > > > > > > > > > > Today's Topics: > > > > > > > > > > 1. Fwd: YOUR E-MAIL ADDRESS WON THE LOTTERY. (Owen Densmore) > > > > > 2. Hurricanes and engines (Eric Smith) > > > > > 3. Re: Fwd: YOUR E-MAIL ADDRESS WON THE LOTTERY. (Russell > Standish) > > > > > 4. Hurricanes, People and Turbulence (Mike Oliker) > > > > > 5. Re: What are Hurricanes? (Robert Cordingley) > > > > > > > > > > > > > > > - > > > > > Hi Nick and all, > > > > > > > > > > Figured all lurk and no pay makes Eric a parasite. > > > > > > > > > > I think Steve is very right about the engine interpretation, and > would > > > > > offer a few details to it. I haven't done the math for this, but > > > > > suspect I can correctly guess qualitative features. > > > > > > > > > > A secondary point of quantification: SFI had a visitor from NOAA > about > > > > > a year ago (I forget her name; she was interested in medium-range > > > > > weather forecasting and how well it stood up under onset of chaotic > > > > > dynamics) who told me that the existence of the cyclonic storm > seasons > > > > > raises the polar temeratures by about 3 degrees in early winter > > > > > relative to what it would be without them. So Steve is right about > > > > > transport of heat from bottom to top of the atmosphere, but one > should > > > > > also appreciate the importance of equator-to-pole transport. I > > > > > suspect this is part of the reason for the tropic-to-temperate paths > > > > > taken by storms in the Atlantic (haven't ever looked at pacific > > > > > storms to see if they do the same thing). > > > > > > > > > > Second point to appreciate is the extreme importance of water in > > > > > distinguishing hurricanes, and this adds to Steve's point, and > changes > > > > > it perhaps a bit. It is not just transport of heat from lower to > > > > > upper atmosphere. The thing hurricanes do systematically is draw in > > > > > cool, relatively dry air from mid to upper atmosphere hundreds of > > > > > miles away, dragging it over the ocean where it can absorb warm > water > > > > > which is then convected upward. The water carries ocean heat into > the > > > > > atmosphere through the specific heat of vaporization, I suspect in > far > > > > > larger degree than through any temperature change. As the convected > > > > > water vapor reaches the upper atmosphere it condenses, releasing the > > > > > latent heat to the air where it can be radiated off to space, and > > > > > releasing the now-cooled water to fall as rain, some of which > > > > > re-evaporates on the way down but much of which falls back into the > > > > > ocean whence it came, replacing the warm water with cold. The air > > > > > transported up in the convective column flows out in dehydrated form > > > > > at high atmospheric levels, to replace the air drawn in at the base > of > > > > > the system to sweep over the ocean. > > > > > > > > > > My guess is that if one compared hurricane convection to disordered > > > > > Benard convection or thunderstorm systems covering the same area, > one > > > > > would find that the hurricane cycles a vastly greater volume of > > > > > atmosphere laterally across the ocean surface, and with that cycles > a > > > > > vastly greater volume of ocean water through the > > > > > evaporation/condensation cycle, and that through that mechanism it > > > > > transports more heat both vertically, and up-lattitude as a > > > > > second-order effect, than disordered storms could. The extent to > > > > > which it seems relevant to recognize that as a function is the > extent > > > > > to which the function, particularly, is relief of a thermal stress. > > > > > The large-scale relief of stress seems to be the "force" (to use a > > > > > word badly) that favors the emergence and stabilization of > > > > > nonequilibrium channels through which the stress is relieved. > > > > > > > > > > Regarding "individuality" at the level of named storms: It is > > > > > interesting that, if we regard the reliability of hurricane form as > > > > > empirical evidence, the most efficient such engine the atmosphere > > > > > finds is one in which the tens of thousands of square miles of shear > > > > > flow are subordinated to the angularly ordered convective system, > most > > > > > notable near the eyewall. In that sense each storm creates > conditions > > > > > that essentially preclude the concurrent formation of other eyewall > > > > > systems in proximity competing for (or driven into existence by) the > > > > > same sources of energy. The exception, of course, being the eyewall > > > > > replacement, in which the instability of extreme angular momenta > > > > > around a very small eye apparently weaken its ability to constrain > all > > > > > the surrounding lateral convection, and the conditions that led to > the > > > > > original eyewall do lead to the formation of a new secondary eyewall > > > > > concentric with the destabilizing one that is on the way out. > > > > > > > > > > I would readily identify this regularity of form with the regularity > > > > > of form of the chemistry in lightning strikes, and probably with the > > > > > regularity of form of certain biochemical pathways. The individual > > > > > who emerges in biology, however, probably does so in response to > > > > > rather different sequences of pressures, even though once emerged, > he > > > > > shares certain "Darwinian" aspects with the individual hurricane. > > > > > > > > > > I have thought for years it would be wonderful to see a book in > which > > > > > a comprehensive suite of mathematical models of hurricanes was > > > > > reviewed, from abstract to quantitatively accurate. If anybody > knows > > > > > of a compact and well-written book, I would enjoy reading it. > > > > > > > > > > Eric > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ------------------------------ > > > > > > > > > > ------------------------------ > > > > > > > > > > Message: 4 > > > > > Date: Wed, 28 Sep 2005 18:08:32 -0600 > > > > > From: "Mike Oliker" <mike.oliker at comcast.net> > > > > > Subject: [FRIAM] Hurricanes, People and Turbulence > > > > > To: <Friam at redfish.com> > > > > > Message-ID: <012701c5c489$f10cd1c0$0300a8c0 at INSPIRON2650> > > > > > Content-Type: text/plain; charset="us-ascii" > > > > > > > > > > Robert's response reminds me of the questions I started the semester > > > with > > > > > when I taught Chaos, Fractals, and Complexity to Honors Undergrads > at > > > UNM: > > > > > (1) What is a Forest that isn't trees? > > > > > (2) What is a Person that isn't cells? > > > > > > > > > > Also, about the Hurricanes thread: > > > > > Is turbulence alive? Looking at a Von Karmen Vortex street > > > > > > > > > > > > > > > (http://www.efunda.com/designstandards/sensors/flowmeters/images/vortex_Karm > > > > > enStreet2.gif) one sees > > > > > a sequence of vortices shed as air goes past an obstruction. I > would > > > > argue > > > > > that each vortex as is shed it creates the perturbation which > assures > > > that > > > > > the next vortex will match it in mirror image. Thus, it is > > reproducing. > > > > > There is an initial period as the air is starting up, where a great > > > > > diversity of turbules (bits of spinning air) arises but these > quickly > > > > evolve > > > > > into a single species (until the wind changes). These vortices are > > > > throwing > > > > > up spontaneous obsticles to the air flow which allows them to gather > > > > energy > > > > > from the flowing wind -- in Stu Kauffman terms they are harnessing a > > > > > thermodynamic work cycle, harvesting energy from their environment. > > > > > > > > > > > Hurricanes are quite similar. They gather vastly more energy by > > > > > facilitating the flow of heat from the warm ocean to the cool high > > > > altitude > > > > > air. They exist in a more diverse environment with many other air > > flow > > > > > species. Where turbulence resolves it's symmetry breaking early and > > > only > > > > > once, hurricanes must do so over and over. They are less effective > > > (thank > > > > > God) at reproduction. > > > > > > > > > > By the way, if galaxies are like hurricanes and turbulence is alive > > ... > > > > > > > > > > -Mike Oliker > > > > > > > > > > > > > > > > > > > > Message: 1 > > > > > Date: Tue, 27 Sep 2005 09:26:49 -0600 > > > > > From: Robert Holmes <rholmes62 at gmail.com> > > > > > Subject: Re: [FRIAM] What are Hurricanes? > > > > > To: The Friday Morning Applied Complexity Coffee Group > > > > > <Friam at redfish.com> > > > > > Message-ID: <8577701505092708263b0f4bd5 at mail.gmail.com> > > > > > Content-Type: text/plain; charset=ISO-8859-1 > > > > > > > > > > On 9/27/05, Jochen Fromm <fromm at vs.uni-kassel.de> wrote: > > > > > > > > > > > > ... Nevertheless, I > > > > > > think it is interesting that hurricanes get names, although they > are > > > > > > non-permanent, volatile and temporary dynamic phenomena. .... > > > > > > > > > > Just like humans :) > > > > > > > > > > > > > > > -------------- next part -------------- > > > > > An HTML attachment was scrubbed... > > > > > URL: > > > > > > > > > > http://redfish.com/pipermail/friam_redfish.com/attachments/20050928/56f43373 > > > > /attachment-0001.htm > > > > > > > > > > ------------------------------ > > > > > > > > > > Message: 5 > > > > > Date: Wed, 28 Sep 2005 19:34:45 -0500 > > > > > From: Robert Cordingley <robert at cirrillian.com> > > > > > Subject: Re: [FRIAM] What are Hurricanes? > > > > > To: The Friday Morning Applied Complexity Coffee Group > > > > > <Friam at redfish.com> > > > > > Message-ID: <433B36A5.5070501 at cirrillian.com> > > > > > Content-Type: text/plain; charset="us-ascii" > > > > > > > > > > There was an interesting article in the NY Science Times: > > > > > > > > > > http://www.nytimes.com/2005/09/27/science/earth/27loop.html > > > > > > > > > > which you might be able to see. The article discusses the dimension > > of > > > > > subsea energy and the depth of warm water needed. So it also > depends > > > on > > > > > subsea counterpart(s) - the loop - and other 'things' which should > be > > > > > considered as the storm makes it's way across our oceans? > > > > > > > > > > Robert Cordingley > > > > > > > > > > > > > > > Douglas Roberts wrote: > > > > > > > > > > > Not to mention; full of hot air. > > > > > > > > > > > > On 9/27/05, Robert Holmes <rholmes62 at gmail.com > > > > > > <mailto:rholmes62 at gmail.com>> wrote: > > > > > > > > > > > > On 9/27/05, Jochen Fromm <fromm at vs.uni-kassel.de > > > > > > <mailto:fromm at vs.uni-kassel.de>> wrote: > > > > > > > > > > > > > > ... Nevertheless, I > > > > > > > think it is interesting that hurricanes get names, although > > > > > > > they are non-permanent, volatile and temporary dynamic > > > phenomena. > > > > > > > .... > > > > > > > > > > > > Just like humans :) > > > > > > > > > > > > <snipped> > > > > > > > > > > > -------------- next part -------------- > > > > > An HTML attachment was scrubbed... > > > > > URL: > > > > > > > > > > http://redfish.com/pipermail/friam_redfish.com/attachments/20050928/455df748 > > > > /attachment.htm > > > > > > > > > > ------------------------------ > > > > > > > > > > _______________________________________________ > > > > > Friam mailing list > > > > > Friam at redfish.com > > > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > > > > > > > > > > End of Friam Digest, Vol 27, Issue 30 > > > > > ************************************* > > > > > > > > > > > > > > > > > > > > > > > > ------------------------------ > > > > > > > > _______________________________________________ > > > > Friam mailing list > > > > Friam at redfish.com > > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > > > > > > > End of Friam Digest, Vol 27, Issue 31 > > > > ************************************* > > > > > > > > > > > > > > > > > > ------------------------------ > > > > > > Message: 2 > > > Date: Thu, 29 Sep 2005 13:17:06 -0600 > > > From: "Mike Oliker" <mike.oliker at comcast.net> > > > Subject: Re: [FRIAM] Friam Digest, Vol 27, Issue 31 > > > To: <Friam at redfish.com> > > > Message-ID: <014001c5c52a$64a217d0$0300a8c0 at INSPIRON2650> > > > Content-Type: text/plain; charset="us-ascii" > > > > > > Nick, > > > > > > (1) The atmosphere is in a high energy state (cool DENSE air on the top, > > > warm THIN air on the bottom, if they can switch places they shift to a > > much > > > lower energy state, but where to break symmetry? Buoyancy drives the > > > system. Humidity comes in to it by keeping the warm air warm much > longer > > > than sensible heat alone can do. > > > > > > (3) If two fluid streams collide, they can either deflect around one > > > another, or undergo mixing. Mixing will only occur if there are strong > > > shears with sharp velocity gradients to mix the streams turbulently. By > > > deflecting when possible, the streams keep the shear forces down, the > > > gradients small, and easily preserve their angular and linear momentum. > > It > > > is the path of least resistance. So, in the free air, they will be > > > deflected mostly, and act as though their boundaries were obstacles. > > > > > > -MikeO > > > > > > -----Original Message----- > > > Message: 1 > > > Date: Wed, 28 Sep 2005 20:26:57 -0600 > > > From: "Nicholas Thompson" <nickthompson at earthlink.net> > > > Subject: [FRIAM] Hurricanes > > > To: Friam at redfish.com > > > Message-ID: <410-22005942922657409 at earthlink.net> > > > Content-Type: text/plain; charset=US-ASCII > > > > > > thank you, Eric, Robert, and Mike for these wonderful posts. I want to > > > consider each in detail, but in the meantime, a few random thoughts. > > > > > > (1) I understand the movement of heat from low latituds to high > lattitudes > > > as a "function" of hurricanes but am less certain about the vertical > > > assymetry in temperature. A stable atmosphere is three to five degrees > F > > > -- average --- cooler for every thousand feet of altitude up to the > > > tropopause ... somewhere around 35kfeet or so. . So, for instance, in > an > > > atmosphere that is, say 80 degrees at the surface is symmetrical if the > > > temperature is, say, zero F at 20 kfeet. (Dont hold me to the exact > > > numbers.) So if temperature cannot be the name of the property of an > > > atmosphere that is UNstable. Are we talking about relative temperature, > > > the lifted index..... what IS that property. Is latent heat the sort > of > > > thing there can be an assymetry in? > > > > > > (2) Having read hundreds of hurricane discussions in the last year > > > assiduously -- some would say obsessively --, I dont get the impression > > that > > > hurricanes are "trying" to go north. They just go wherever the wind > blows > > > them. The currents that move them along are miniscule compared to the > > > currents within the storm, which is why I asked if a hurricane is more > > like > > > a top, a whirlpool, or a dervish. Hurricanes start where it is warm and > > are > > > dirrected by the currents that move along the bottom of a subtropical > > high. > > > When they hit the west end of the high they turn north. > > > The reason they appear to be a north-going thing is that they start in > the > > > south and if they get north they die. but they can as easiy be carried > > > south if they get into a south moving current. over water that is warm > > > enough to sustain them. Every rare once in a while, when the bermuda > > high > > > pressed low enough a hurrican (or tropical storm) will come up the coast > > of > > > the US, turn eastward over the atlantic, travel back toward africa, and > > > then head south around the EASTERN end of the Bermuda High. The > Bermuda > > > High is itself a mixer but so far as the high is concerned, if a > hurrican > > > wants to walk around the top of it to africa, it is happy to comply. > > > > > > (3) Finally, I wonder if anybody could help with the intuition block > that > > > makes it difficult for me to think of a whirling column of air as an > > > obstacle. I can see how it might suck me in but I cannot see how it > might > > > bounce me off. > > > > > > Nick > > > > > > Nicholas S. Thompson > > > Professor of Psychology and Ethology > > > Clark University > > > nickthompson at earthlink.net <http://home.earthlink.net/~nickthompson/> > > > http://home.earthlink.net/~nickthompson/ > > > nthompson at clarku.edu > > > > > > > > > -------------- next part -------------- > > > An HTML attachment was scrubbed... > > > URL: > > > http://redfish.com/pipermail/friam_redfish.com/attachments/20050929/3d5191a0 > > /attachment-0001.htm > > > > > > ------------------------------ > > > > > > Message: 3 > > > Date: Thu, 29 Sep 2005 14:46:38 -0600 (MDT) > > > From: "Eric Smith" <desmith at santafe.edu> > > > Subject: [FRIAM] shear, shear, and migration > > > To: Friam at redfish.com > > > Message-ID: <200509292046.j8TKkKGI016017 at kakapo.santafe.edu> > > > Content-Type: text/plain; charset=US-ASCII > > > > > > Hi Nick, > > > > > > Unfortunately, given that I find them interesting, the amount I don't > > > know about Hurricanes fills volumes. On the other hand, I think you > > > are a victim of language, created because weather people, like > > > everyone else, never speak in complete sentences. > > > > > > So first, to shear and Shear. Scale matters here. A Hurricane is a > > > structure of shear flows. Unless I am terribly missing the point, > > > that is why it spins, why the eyewall has the structure it does, etc. > > > Shear is what makes the coriolis force matter. A net influx of air > > > toward the eye (shear over the ocean) at low level causes > > > more-equatorial air to move northward and more-polar air southward. > > > Because they keep some of their angular momentum, the more-equatorial > > > air has a net eastward velocity relative to the more-polar component. > > > This angular momentum conservation creates the vortex, and the fact > > > that the low pressure in the central regions is only capable of > > > supporting a limited centripetal force causes the influx to stop at a > > > nonzero radius, leaving the eye. I think that this is why wind speed > > > in the storm is directly related to (and caused by) the pressure > > > reduction in the eye (there is also some Bernoulli relation relating > > > pressure and velocity in the eyewall with pressure and stillness in > > > the eye, which would provide a different-looking equation to arrive at > > > the same result). > > > > > > Some of the angular momentum is not convected, because the air has > > > friction, so the total angular momentum at the top of the convection > > > system, where it must flow back out (shear at high altituted) is not > > > what it brought in with it. Hence there is a negative velocity of the > > > more-equatorial air near the eye now going back toward the equator, > > > and the more-polar air near the eye going back toward the pole. So we > > > get spiral flow at the top in the antisense of the flow at the > > > bottom. All this is shear, but it is shear at the scale of the > > > substructure of the storm itself, rather than net Shear at the scale > > > of the whole atmosphere. > > > > > > I assume, though I can't back it up, that the form of shear weathermen > > > speak of as disruptive of hurricanes, is Shear on the scale of the > > > whole atmosphere, which is transporting and dissipating angular > > > momentum in lattitude in other ways than those that form a clean > > > vortex. Think of stirring the water going down the drain, and how > > > that can inhibit the formation of a drain vortex. That is a > > > disruptive Shear phenomenon, but the vortex itself, when it forms, is > > > also a shear phenomenon. > > > > > > Re polar migration. Thank you for providing a lot of detail I didn't > > > know about that. Perhaps I should have been thinking of the oceans as > > > the place to look for the original polar motion, though that seems too > > > limited. I thought that the gulf stream runs northward near the > > > surface, warming England and Scotland, but where it gives that heat up > > > to the atmosphere, the water cools and dives, returning to the equator > > > in the deep mid-atlantic, where it eventually wells up, is reheated by > > > the sun, and meanders (via loop currents or however) back northward. > > > If that is correct, then what you say about Hurricanes following ocean > > > tracks would be consistent with northward tendencies, because the > > > ocean currents go north at the surface to be cooled. (Please pardon > > > the intentional language here. They do what they do because they > > > solve differential equations, where sinking leaves a low pressure that > > > draws in warm surface water, etc. It is easier to assume we all know > > > there is some such mechanics behind it and encode that in saying "to > > > be cooled".) I still tend to expect that, with all sorts of > > > variations and stochasticity, there is a larger principle here that > > > governs atmosphere and oceans through whatever coordinated currents: > > > that heat is delivered mostly in the equator and tropics, and > > > dissipates as uniformly as it can (meaning, limited by the degree to > > > which temperature can be equalized) over the globe. Thus net > > > transport of heat from equator and tropics to poles is the background > > > leading to all the various currents. There is a lot more heat in the > > > oceans than atmosphere, in addition to which that is where most of > > > the sunlight is actually absorbed and converted to heat. So it would > > > be reasonable that the oceans are the big engine, and the atmosphere > > > follows along. > > > > > > Anyway, all most interesting... > > > > > > Eric > > > > > > > > > > > > > > > > > > > > > > > > > > > ------------------------------ > > > > > > _______________________________________________ > > > Friam mailing list > > > Friam at redfish.com > > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > > > > End of Friam Digest, Vol 27, Issue 32 > > > ************************************* > > > > > > > > > > > > ------------------------------ > > > > Message: 2 > > Date: Fri, 30 Sep 2005 08:20:56 +1000 > > From: Russell Standish <r.standish at unsw.edu.au> > > Subject: Re: [FRIAM] Friam Digest, Vol 27, Issue 32 > > To: nickthompson at earthlink.net, The Friday Morning Applied Complexity > > Coffee Group <Friam at redfish.com> > > Message-ID: <20050929222056.GA1016 at mpi.NSW.bigpond.net.au> > > Content-Type: text/plain; charset=us-ascii > > > > On Thu, Sep 29, 2005 at 05:26:32PM -0400, Nicholas Thompson wrote: > > > > > > I am sure you are right that the oceans are the key. The power of the > > > oceans to store heat is amazing. It is really true that the oceans are > > > warmest around sep 1 and coldest around jun 1. > > > > > > > Northern hemisphere perhaps. I was swimming in the oceans around here > > during June, and the water temp was lovely. On the other hand I went > > for a brief dip a couple of weekends ago, and it was rather chilly. I > > don't expect it to really warm up until mid-December. > > > > Cheers > > > > -- > > *PS: A number of people ask me about the attachment to my email, which > > is of type "application/pgp-signature". Don't worry, it is not a > > virus. It is an electronic signature, that may be used to verify this > > email came from me if you have PGP or GPG installed. Otherwise, you > > may safely ignore this attachment. > > > > > ---------------------------------------------------------------------------- > > A/Prof Russell Standish Phone 8308 3119 (mobile) > > Mathematics 0425 253119 (") > > UNSW SYDNEY 2052 R.Standish at unsw.edu.au > > Australia > http://parallel.hpc.unsw.edu.au/rks > > International prefix +612, Interstate prefix 02 > > > ---------------------------------------------------------------------------- > > > > > > > > ------------------------------ > > > > _______________________________________________ > > Friam mailing list > > Friam at redfish.com > > http://redfish.com/mailman/listinfo/friam_redfish.com > > > > > > End of Friam Digest, Vol 27, Issue 33 > > ************************************* > > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9:30a-11:30 at ad hoc locations > Lecture schedule, archives, unsubscribe, etc.: > http://www.friam.org -- *PS: A number of people ask me about the attachment to my email, which is of type "application/pgp-signature". Don't worry, it is not a virus. It is an electronic signature, that may be used to verify this email came from me if you have PGP or GPG installed. Otherwise, you may safely ignore this attachment. ---------------------------------------------------------------------------- A/Prof Russell Standish Phone 8308 3119 (mobile) Mathematics 0425 253119 (") UNSW SYDNEY 2052 R.Standish at unsw.edu.au Australia http://parallel.hpc.unsw.edu.au/rks International prefix +612, Interstate prefix 02 ---------------------------------------------------------------------------- |
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