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Technology Science

Supercomputers Race to Predict Storms 184

pillageplunder writes "CNN has an interesting article on how different supercomputers from around the world are working to predict large storms tracks. The 3 days it takes now has been cut in half. Cool read."
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Supercomputers Race to Predict Storms

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  • Earth Simulator (Score:1, Redundant)

    by CyberBill ( 526285 )
    Isnt predicting the weather the job of that huge ass supercomputer in Japan? I think it is called Earth Simulator, but I am not sure... I remember a post about it awhile ago, and it showed all of the racks being 'crooked' because it allowed the heat from the processors to actually rise out of the case, and not stay in the rack. :P
  • Oh wait, that's the job of the Diebold supercomputer.
  • Twister (Score:5, Funny)

    by Transient0 ( 175617 ) on Thursday September 16, 2004 @10:40AM (#10266786) Homepage
    I'll be impressed when I see supercomputers chasing tornadoes around Kansas in rusty pickup trucks. Not before.
    • Re:Twister (Score:4, Interesting)

      by Orp ( 6583 ) on Thursday September 16, 2004 @11:57AM (#10267805) Homepage
      I'm modeling supercells that produce tornadoes (well, almost) using supercomputers... does that count?

      A talk I just gave a few days ago on this is found at the below link. Both in OpenOffice and PPT format. Note: the mpegs in that directory are BIG (1024x768) but they are very cool animations of supercells (raytraced with POV-Ray) and tornado-like circulations.

      http://research.orf.cx/uw2004 [research.orf.cx]

      Leigh Orf


      • I'm modeling supercells that produce tornadoes

        [Pardon me for taking advantage of your expertise]...So two questions have bugged me for a while.

        Q1: Once I read where there seemed to be the possibility that tornadoes could be driven by magnetohydrodynamic forces [Nalivkin, 1963]. Is that plausible, credible, or are density variations due to thermal buoyancy enough to account for the observable physics of tornadoes?

        Q2: What is it - really - that causes lightning? I've heard hand waving arguments about ice

  • the 3 days it takes? (Score:5, Informative)

    by Kr3m3Puff ( 413047 ) * <me@kit[ ]kelly.com ['son' in gap]> on Thursday September 16, 2004 @10:41AM (#10266797) Homepage Journal
    Actually if you read the article you will realize that it only takes about an hour of number crunching, but that the three day storm path accuracy errors have been cut in half... and that 5-day forcast is getting much more accurate.

    I guess we should read articles before submitting them...
    • by bhima ( 46039 ) <Bhima@Pandava.gmail@com> on Thursday September 16, 2004 @10:51AM (#10266922) Journal
      If we're not RTFA why should the submitter?
    • and that 5-day forcast is getting much more accurate.

      And much less free on weather.com. Who decided to do that anyway? Charge for a best-guess on a 5-day forecast? I can see that for free on my rabbit ears on the TV.

      • Where do you see Weather.Com charging for 5 day forcasts? I RTFA, and then went to Weather.com and managed to get a 10 day forcast in a matter of 2 clicks.. for free. Seems like a silly business model. Charge for 5 day, give them 10 for free? :)

        Just plug in your zip code [weather.com]
        • Oh thank God they took it off. I quit going there when it would pop up & ask me for $$ for a 5 day forecast. I guess nobody signed up & it produced nothing but an angry mob ;) Thanks for the update though. Now I can start going there again to see more than current weather.
    • by Anonymous Coward
      3 day stormcasts are about twice as accurate as 40 years ago they tend to be off on average by only 400 nautical miles. 5 day forecasts are completely worthless and neither of them ever predict where the storm actually goes anyway so it kind of doesn't matter.

      Personally living in New Orleans (10 feet below sea level) it's comforting to know that the forecasts are only off by 400 miles now.
      /SARCASM

    • I don't think that they explicitly claimed that the forecast that takes an hour is a 3 day forcast.. I'd expect that it would be for a 5 day forecast, with the 3 day forecast being ejected mid stream.

      My thesis is that the confusion came from the last sentence that: "If we took three days to do a three-day forecast, it wouldn't be relevant."

  • by alatesystems ( 51331 ) <chris@[ ]isbenard.net ['chr' in gap]> on Thursday September 16, 2004 @10:41AM (#10266801) Homepage Journal
    I like how the article says: Just as a 5-megapixel digital camera more accurately depicts reality than a 1-megapixel device, higher resolution grids can capture a better picture of the atmosphere and help produce accurate forecasts.

    Way to pitch to the high-tech crowd CNN :)

    But....... imagine a beowulf cluster of these weather predicting supercomputers.

    Chris
  • by BalorTFL ( 766196 ) on Thursday September 16, 2004 @10:44AM (#10266836)
    ...but still not as fast as "nowcasting" (and yes, it's an actual meteorological term.) I've always wondered why the local news just has to tell us, "And in downtown it is currently raining at the moment." The people who go outside already know, and the rest of us don't care.
    • It's still pretty bad that a lot of weather stations changed from calling it a forecast and refer to it as a "Futurecast". I really doubt futurecast is a valid meteorological term.
    • Don't live in Michigan, eh? Around Saginaw, it's been regularly observed where people living near State Street and Mackinaw can be hit with a thunderstorm strong enough to blow out the windows on the Kessel's supermarket, and people at Hemeter and State (less than 1/2 mile away) have no rain, minimal wind, and can even see the sun. Those nowcasts are pretty useful, since I always know that whatever's hitting the business district on Brockway will usually hit where I am in a half hour or so.
  • by YetAnotherName ( 168064 ) on Thursday September 16, 2004 @10:44AM (#10266840) Homepage
    The models -- actually complicated software written in a computer language called Fortran -- attempt to account for everything happening in the atmosphere on a global basis.

    Well no wonder weather prediction is so off!

    I kid, I kid ... actually I used to work for the National Weather Service ... C++, Tcl/Tk, and even Fortran ...
    • Fortran, yay! (Score:5, Interesting)

      by green pizza ( 159161 ) on Thursday September 16, 2004 @10:50AM (#10266911) Homepage
      You don't know too many scientists-turned-programmers do you? Fortran is still alive and well in scientific circles. Companies like IBM and SGI still write and optimize Fortran compilers for their newest CPUs. Even Intel recently released a major update to their P4 and Itanium2 Fortran compilers.
    • Re:Fortran? Eyew. (Score:4, Informative)

      by flaming-opus ( 8186 ) on Thursday September 16, 2004 @11:02AM (#10267073)
      Fortran is still the dominant language for programming high performance code. I'd still rather use C, but it's not really that different. When you're trying to optimize a piece of software for a machine architecture you need to use a language that is pretty low-level. The closer to assembly you are, the greater chance you have to best exploit the functionality of the hardware. C++/Java are right out.
      • From what I remember from reading the optimization guidelines for a SGI O3400 box (a few years ago when it wa brand new), Fortran code is easier to automatically optimize then C code is. I believe it has something to do with the use of pointers in C.
    • Re:Fortran? Eyew. (Score:3, Insightful)

      by Jeff DeMaagd ( 2015 )
      This sort of code is probably heavily matrix oriented. Fortran handles matrix operations, making matrix operations as easy to program as simple arithmetic.
      • I think the major reason Fortran is used is because of legacy algorithms (and legacy programmers!)
        • I think the major reason Fortran is used is because of legacy algorithms (and legacy programmers!)

          This is a common misconception, that Fortran is somehow a dead, legacy language. However, it so happens that this myth is even easier to dispel today, than on most other days. Why? Because news has just been posted to the comp.lang.fortran newsgroup that the Fortran 2003 standard has just been ratified.

      • Fortran also has built-in complex mathematics. No need for subroutines and macros (which just slow down computing and/or compiling).

        Many of the most famous Fortran computational libraries have long since been translated into C and other languages, but when you have millions of lines of perfectly functional (and reasonably complicated) Fortran production code, moving to something like C is a difficult decision, especially when you have limited value in the move.

        As someone else pointed out: C is close to

  • by Anonymous Coward
    If easy-for-geeks-to-build home weather sensors were available, this would be a cool SETI-at-home-like project that would let hardware geeks have fun with distrubited computing too.
    • As others have already noted, this isn't a SETI-type problem. Whereas SETI has a large amount of data that must be parsed, analyized, etc. individually, a CFD simulation requires inter-node communication, meaning each portion of the solution that is running in parallel must be able to communicate with other portions. For a distributed environment, sometimes things like gigabit ethernet just aren't fast enough--hence the market for myrinet and infininet. Many times for a complex problem bandwidth is more
  • by hey ( 83763 ) on Thursday September 16, 2004 @10:45AM (#10266851) Journal
    The storms will hit the Caribbean and Florida in September.
  • From the article:
    ...complicated software written in a computer language called Fortran...
    Huh. Not Java, or maybe even Ruby [ruby-lang.org]? What's the maintenance burden like for a large body of Fortran code?
    • Fortran is still used in many applications. Obviously it's what was used when the program was first started, and it easier to continue on in the same language at this point, than to start over in a new language.

      They're also primarily concerned with performance over other things; this would definitely influence their opinion if they were to adopt a new language (as opposed to maintainability and/or portability).
      • > easier to continue on in the same language

        True, yup, that's usually the case.

        > primarily concerned with performance

        Hm. I'm not familiar with supercomputers... does Fortran have some sort of built-in support for being run on them? Like some sort of special internal JIT compiler or something?
        • A JIT shouldn't be necessary for something that's already been compiled to run natively on a particular processor. JIT compiling deals more with emulation.
        • Hm. I'm not familiar with supercomputers... does Fortran have some sort of built-in support for being run on them?

          Yes, it does. There is a Fortran 95 language variant known as High-Performance Fortran (HPF), specifically targetted at coding for parallel computers. Fortran also sits very well with OpenMP [openmp.org].

          Fortran does not need a JIT, since it compiles straight to machine code rather than intermediate bytecode.

    • Not bad. Anyone who knows 'C' can learn fortran in about a day. It's a pure indicative language, plain and simple.

      What's more difficult is continually optimizing for the various machine architectures. The processor clocks are generally improving faster than the memory latency or network latency. So mitigating those is becoming a much bigger part of the puzzle.
      • > Anyone who knows 'C' can learn fortran
        > in about a day

        Cool.

        > What's more difficult is continually
        > optimizing for the various machine architectures

        Hm, that's interesting. Is that something that would be done in Fortran using some sort of pragma-ish hints? Or is it something the Fortran interpreter writers would be mostly concerned with?

        Googling a bit reveals a couple of Fortran compilers [google.com]... seems like that's where the per-architecture optimization would happen. But maybe the "end-user"

        • > What's more difficult is continually
          > optimizing for the various machine architectures

          Hm, that's interesting. Is that something that would be done in Fortran using some sort of pragma-ish hints? Or is it something the Fortran interpreter writers would be mostly concerned with?

          Googling a bit reveals a couple of Fortran compilers... seems like that's where the per-architecture optimization would happen.


          Yes, most of the optimizations for specific hardware concern only compiler writers. Just like
    • Fortran is a abbriviation for Formula Translation.

      I hope you understand now why Fortran is still used in scientific and banking computing.

    • What's the maintenance burden like for a large body of Fortran code?


      Roughly speaking, about half that of a comparable C program.

      Speed-wise, Fortran is about as good as it gets unless you want to go into asm. Fortran aliasing rules allow more aggresive optimization than C/C++ (although in this regard C99 achieves the same thing with restricted pointers). Also, the current Fortran version, Fortran 95, has a slightly matlab-like array language, where you can express many computations directly as whole arr
  • by ARRRLovin ( 807926 ) on Thursday September 16, 2004 @10:45AM (#10266857)
    Next they'll have sensor strapped to the back of every butterfly on earth, increasing hurricane predictability 10 fold.
    • >> Next they'll have sensor strapped to the back of every butterfly on earth, increasing hurricane predictability 10 fold

      Except for the Butterfly effect where one little change can cause something major to happen elsewhere.

      All that extra weight will change the butterflies flight pattern, causing all sorts of screwy weather conditions, the end of the world, Dogs and cats living together and mass tifoil hat wearng hysteria.

      if you can find the joke above you aren't smart enough to read it to begin wit
    • Next they'll have sensor strapped to the back of every butterfly on earth, increasing hurricane predictability 10 fold.
      Seems like it would be simpler to just exterminate all butterfly species, and thus eliminate hurricanes forever! :)
    • If we did it to every butterfly on earth, wouldn't it cancel out, or affect weather elsewhere, like on the moon?

      Maybe we could terraform Mars this way.

      Hmm, maybe I should be posting this to the USPTO instead of /., after all, I have an idea AND the implementation!

  • Best line (Score:5, Funny)

    by GraWil ( 571101 ) on Thursday September 16, 2004 @10:46AM (#10266871)
    The models -- actually complicated software written in a computer language called Fortran -- attempt to account for everything happening in the atmosphere on a global basis.
    As someone who spends days (and many nights) extending and debugging crufty old radiative transfer models within numerical weather prediction code, FORTRAN [faqs.org] is the rule, not the exception. What is this c++ everyone on \. keeps talking about?
  • Wonderful journalistic number in the summary. Predicting storm paths now take only 1.5 days compared to 3 days before. As it happens I can predict where a storm will go in 24 hours in less time than 1.5 days (in fact, I might be able to tell several minutes before it even gets there!). Without any context that number is completely and in every way useless.
  • NOAA (Score:5, Interesting)

    by garretwp ( 790115 ) on Thursday September 16, 2004 @10:49AM (#10266895)
    I currently work for NOAA at a facility called GFDL. We house some of the super computers here. I currently operate and control the computers and its deffinitly a treat to be able to work with these fast machines. We have some of the worlds fastest computers here and they compete very well with the earth simulator. We also have some of the top hurricane guys working for us as well. It is good to see that the techonology that we use is getting publicity. It will inform everyone how things are done and where they get the information from.
    • If I email you my resume, could you sent it to somebody who might hire me? I'm a computer scientist with a love for weather, especially hurricanes!

      My long term goal is to have a PhD in CS and meteorology, probably combining both theses into one big project. :-) (And I'm serious too)
  • by Council ( 514577 ) <rmunroe&gmail,com> on Thursday September 16, 2004 @10:56AM (#10266993) Homepage
    You can see the current predictions by each model at any given time here:
    http://www.weatherunderground.com/tropical/trackin g/at200406_model.html [weatherunderground.com]

    The NHC discussion of the model guidance for each storm is here, under 'discussion' for each storm:
    http://www.nhc.noaa.gov/ [noaa.gov]

    They explain why they're agreeing with or discounting each model in their overall forecasts.

    Generally, it's difficult to find much prediction of hurricane tracks that doesn't come somehow from the NHC. This isn't because there aren't independent analysists, but because they try not to send mixed signals, which might lead to people not evacuating when they should. The raw information from the computer models is the closest you get to dissenting opinions, afiak.
  • You have to wonder.. (Score:4, Interesting)

    by dfj225 ( 587560 ) on Thursday September 16, 2004 @10:56AM (#10266996) Homepage Journal
    To a casual observer of the weather, like me, it seems that the paths of the hurricanes are little more than extrapolations of the current path with a slight bend to the east. For the hurricanes this year, it seems that time and again the models proved wrong for last minutes changes to the storm. I know from family who lives on the west coast of Florida that many people were caught off guard by Charlie. I really think that it is probably impossible to accurrately predict the path of a storm. I mean I could take a look at the motion of the storm and guess about as accurately as the models guess. My same family that was caught off guard by Charlie headed to Orlando when Ivan was about a week away, but the storm didn't land near their house. If you think about it, 3 days notice is not enough to have every person in a metropolis patch up their houses and move to higher ground. Some might say that everyone with the possibilty of getting hit by the storm should prepare, but imagine having to board your windows every 3 weeks or so only to be missed by the storm. It would be even worse if you evactuated on the same schedule. This would make it very difficult to live a normal life. Honestly, the prediction of storms like hurricanes needs to get much better, but I doubt that it ever will.
    • It's easy to think this looking at the paths, but it is not true. Guidance is generally greatly affected by the placement of high-pressure ridges and their future erosions/strengthenings. Frances could have just as easily turned harmlessly to the north had there not been a strong ridge keeping it where it was, and Ivan could have headed east to Mexico had the ridge to the north not eroded. In both cases, they behaved roughly as predicted. The paths of hurricanes are predicted fairly accurately these day
    • Big difference between casual observer and what the people doing the modelling are doing ;) To predict the EXACT track/intesnsity/storm surge/rainfail is going to be impossible...there are just way too many factors that determine what any particular storm will do at any given time. Same thing with earthquakes, flashfloods, tornadoes, etc. Have you read any of the Discussions on the National Hurrican Center's website for storms? They have many different models and then try to figure out which one is more acc
    • If you think about it, 3 days notice is not enough to have every person in a metropolis patch up their houses and move to higher ground. Some might say that everyone with the possibilty of getting hit by the storm should prepare, but imagine having to board your windows every 3 weeks or so only to be missed by the storm.

      The boarding-up problem can probably be simplified with rigid mount points and locks on pre-fitted panels. I'm sure a solution can be designed for second story windows where it can be ins
  • Almost every NOAA scientist that I know (NB: I know quite a few) is proficient in Fortran [faqs.org] and IDL. This is the norm in atmospheric science.
  • See the models (Score:5, Interesting)

    by theCoder ( 23772 ) on Thursday September 16, 2004 @11:06AM (#10267124) Homepage Journal
    As a resident of Florida (who's so far been pretty lucky with respect to the hurricanes), I've taken a keen interest in these models. The best place I've found to see them is at Weather Underground [wunderground.com]. Each listed storm has a "Computer Models" link at the end. See

    Ivan [wunderground.com]
    Jeanne [wunderground.com].

    Since the pages auto-refresh, I've just been leaving them up in a tab in Mozilla and checking them every once and a while. Though the models aren't always accurate and tend to change a lot, they kind of give you a feel for where the storm is probably going to go.
    • From the looks of the Ivan link, it appears as if the entire South Eastern United States will be destroyed in a few days.
    • Hey speaking of the maps and models, anyone know where they are generating the nice 3D looking views as if from orbit, but it looks like the heights are exaggerated and the rendering is fairly high quality? I've seen a few here and there this hurricane season but it would be nice to find the source.
  • A long way to go... (Score:2, Interesting)

    by fafalone ( 633739 )
    Living in Florida I've spent a whole lot of time looking at track modelling in the past month. For hurricane Frances at one point, the cone of error of eye movement was over 90 degrees, as in they had no clue which direction the storm would be moving an hour from when the model was made. In Charley, their predictions were over 100 miles off for the eye only a couple hours before landfall (which really sucked for me since the eye hit land only 30 miles away). And since that happened, the margins of error for
    • The NHC does do that if you read their discussions. The forecasters take the model output and input their own experience and observations (the ridge over Bermuda isn't as strong as the model initialized it to be, one model predicted a trough to dig in 100 miles further than it actually did, etc.) When they say they favor the GFDL, or NOGAPS, or , they'll adjust the forecast accordingly.

      Interestingly, they've still been off (100 mi. east w/ Charley, 300 mi. west w/ Ivan) and that's just because hurricanes a

  • The New York Times had a similar story [nytimes.com] two days ago. Ironic that CNN would take two extra days to get a story about forecasts being extended out by two days.
  • It would be interseting to see a figure releating 1)real-world sample density and 2)computer power in flops and 3)choice of algorithm to 4) prediction accuracy.
  • After closely watching the hurricanes and their projected paths develop this year, I've noticed that their predictions hold pretty well... until the hurricane nears land.

    Charley swerved just before landfall, Frances stopped dead in the water 60 miles off Florida, and Ivan "bounced" off Jamaica, shifting its path by 500 miles, none of which were predicted. Possibly, none of which are predictable. If you can't warn people where landfall will occur when it takes some non-obvious path, then what's really the

    • Re:Land seem chaotic (Score:4, Informative)

      by jellisky ( 211018 ) on Thursday September 16, 2004 @12:40PM (#10268370) Journal
      Landfall dynamics are a VERY active point of research in hurricanes right now. Land changes a lot of variables which we can normally take for granted in a hurricane over the water... the surface has different properties, elevation changes make the air behave differently, land doesn't evaporate near as much water vapor as the ocean, etc.

      So, with land, you leave the realm of an initial value problem with relatively well-understood boundary conditions that you have with a storm over the ocean to a realm that has much-less-well-understood boundary conditions. The problem becomes much harder to close, much less solve. And with a system like the hurricane which REQUIRES good knowledge of the boundary (after all, the hurricane is fueled by latent heat release by condensation of water vapor which comes from the ocean), not knowing the boundary as well as you can makes prediction much much harder.

      Charley's swerve was forecast by a good number of models, but NHC played the worse case scenario card a little too long by persisting on a landfall near Tampa Bay.

      Frances' stop was due to a very irregular pattern, much like a saddle point. If you are pushed any direction, you get very different behavior. You can see that on the following model ensemble plot... there's a small cluster of 48 hour predictions that are slower than the others.
      http://euler.atmos.colostate.edu/~vigh/gu idance/at lantic/store/early_AAL06_04090300.png

      Ivan's bounce off Jamaica is a seriously cool research topic, since Jamaica is a mountainous island. That big elevation change could make it more "visible" to the core of the storm (unlike the plains of Florida). This will be a serious research topic for decades to come. Many of the models did not handle it well (which isn't too surprising since Jamaica is a relatively small island and the models that are used frequently are global or near-global models). And some previous storms (Gilbert, 1988) didn't even notice Jamaica as they passed over, so experience is a split decision.

      So, hopefully that sheds a little insight on this issue. Land is a BIG problem for track forecasting, and we're just starting to work out the kinks.

      -Jellisky

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