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Comment Re:Likely a new gift for the NSA (Score 2) 219 219

You are basically describing ensemble forecasting, which is very powerful for providing statistically meaning forecasts where you can intelligently talk about the uncertainty of the forecast, something single deterministic forecasts cannot do.

In my research, I'm doing single deterministic forecasts to study what happens with tornadoes in supercell thunderstorms, where I am cranking up the resolution to capture flow that is otherwise unresolved. I get one version of a particular storm, which is good for studying certain aspects of storms, but not good at being able to generalize (that takes lots of simulations).

Both big deterministic simulations and ensembles have their place. Of course, today's big simulation can be the resolution of tomorrow's ensembles! Right now, you can do lots of good science with ensembles. Operationally (weather forecasting) this is basically the new paradigm, although forecasters are slow to change from just looking at the single deterministic GFS and NAM forecasts. The ensemble approach, once we start running hundreds of forecasts at higher resolution that we do today, will transform our forecasting accuracy (and precision). However it will be limited to the amount of good observational data we can feed the models (otherwise GIGO). This is where remote sensing comes in. GOES-R will be a big help.

It will indeed take people from atmospheric science, computer engineering, software engineering, etc. working together to best exploit exascale machines. NCSA understand this and that's what makes it (and other similar organizations) great.

Comment Re:Likely a new gift for the NSA (Score 1) 219 219

One of the biggest problems of the current large scale HPC machines is users (like you but maybe not you specifically) are typically scientists/analysts who write software that does not scale well. There either needs to be better frameworks for you to work within that handle all the grunt work of doing efficient parallelization and message passing or every atmospheric physicist needs to be teamed with a computer scientist and a software engineer.

Absolutely agree 100%!

Comment Re:Likely a new gift for the NSA (Score 1) 219 219

You can say "one of" but you can't say "the fastest" petascale machines my friend

http://www.hpcwire.com/2012/11...

I should have added "on a college campus".

My main point is, just throwing more cores at "mostly MPI" weather models is not sustainable. We are going to need to be much smarter about how we parallelize.

Comment Re:Likely a new gift for the NSA (Score 5, Informative) 219 219

Weather guys want this after NSA's done.

I'm a weather guy - running cloud model code on Blue Waters, the fastest petascale machine for research in the U.S. I don't think we've managed to get any weather code run much more than 1 PF sustained - if even that. So it's not like you can compile WRF and run it with 10 million MPI ranks and call it a day. Ensembles? Well that's another story.

Exascale machines are going to have to be a lot different than petascale machines (which aren't all that different topologically than terascale machines) in order to be useful to scientists and in order to no require their own nuclear power plant to run. And I don't think we know what that topology will look like yet. A thousand cores per node? That should be fun; sounds like a GPU. Regardless, legacy weather code will need to be rewritten or more likely new models will need to be written from scratch in order to do more intelligent multithreading as opposed to mostly-MPI which is what we have today.

When asked at the Blue Waters Symposium this May to prognosticate on the future coding paradigm for exascale machines, Steven Scott (Senior VP and CTO of Cray) said we'll probably still be using MPI + OpenMP. If that's the case we're gonna have to be a hell of a lot more creative with OpenMP.

Comment Re:This is a GODDAMN DISASTER! (Score 2) 179 179

Bitcoin leaves open the problem that people can scam you and take your money. Credit card companies and paypal and what have you mitigate that problem, but do so at the cost that people can falsely accuse you of scamming them and taking your money, pretend to pay you but don't, confiscate or freeze your money with little accountability, and do a lot of other nasty things.

Are the ways to abuse the system worse than the things the system is supposed to protect you against? I don't know. But it's a valid question - one that is likely to have different answers at different times and places. The answer may vary for different people too. For that reasons, bitcoin is a good thing. Whether the wild west mentality is better is one thing, but having the option of the wild west mentality can't really be bad.

Comment Re: Tesla Is Good For All (Score 4, Insightful) 356 356

And that has been Tesla's argument for the last ten years, yet they still lose about $9,000 on each car they make.

"On" each car, or "for" each car?

"On" makes it sound like their marginal costs are negative -- that, literally, producing one more car increases their losses by $9K. Were it "for" each car, then they're losing money only after fixed costs, R&D, etc. are taken into account.

That latter makes considerably more sense -- folks can legitimately decide to back a company investing in itself rather than taking out a profit; indeed, Amazon has done that for years.

Comment Re:Heart valves? Refrigerators? Pah! (Score 3, Interesting) 65 65

please enlighten us as to why the fountain pin and/or feathered quill is superior to the free pens I get from the bank?

Y'know, I actually don't mind giving this a serious answer.

You don't need pressure to write with a fountain pen -- at all. (The modern competitor is a rollerball, not a ballpoint; rollerballs don't give you amount of flexibility on nib grind or opportunities for flex and shading effects that you get with a fountain, but at least you're not forced to use tons of pressure). Allows different, more comfortable grips.

Also, they're refillable with water-based inks -- meaning that they're not disposable, and that you have a huge amount of choice in terms of color and properties of your ink. Want an ink that's still viscous in below-freezing weather? I've got a bottle on my desk! Want an ink that changes from yellow to red depending on how much you're putting down on the paper? That too! Want an ink that responds to ultraviolet and is completely waterproof you can mix in with other inks that are water-soluable, so you can see where writing that's been washed away used to be under a blacklight?

Lots of room for geekery. :)

Comment Re:Straw vegans (Score 1) 94 94

Far opposite from the truth. I'm no vegan myself -- but growing meat animals requires vastly more inputs (grain, water, etc) than would be needed if skipping the (delicious) intermediate step. Humans consume less grains in sum when consuming them directly, rather than via an intermediate layer.

Comment Re:Not yet statistically significant (Score 1) 408 408

Well it is interesting in so far as knowing when the companies think they need to have human operators still.

Actually, having a licensed human operator ready to take over is a legal precondition for putting an autonomous car on the road (in all US states where they're legal at all).

Comment Re:Well done! (Score 1) 540 540

Prepare for another culture-shock, my dear passport-less American. Tokyo has competing privately-owned subway lines. Japan's wonderful highspeed trains are privately-owned too.

Which shock would this be, exactly? Major American cities used to have competing privately-owned commuter rail lines as well -- mostly torn down in the first half of the 1900s in favor of the highway model. This is by no means a surprise to anyone who knows even local transportation history.

If a government is doing it, it can not be smart...

You lecture me about fallacies, and then pull out that?! I find it hard to believe that you're actually interested in making a good-faith attempt at a meeting of the minds.

Comment Re:Damn... (Score 1) 494 494

(lest see, how liberals who like to say that "you have rights for your opinion" and then mumble "but only, if we agree" assholes are going to react :)

Since you asked -- having a right to an opinion doesn't mean having a right to be protected from social consequences from your actions taken in airing that opinion.

Which is to say -- you're allowed to be an ass in public. Other people are allowed to be an ass to you in public as well; such is the market of public ideas. Mistaking people who don't want to be friends with you / listen to you / do business with you in response to your positions with people who would censor you (that is, invoke government action in response to your speech or act to make make that speech illegal) is a mistake.

You might ponder what it means that you believe in what you're saying enough to shout it from the world only from a position of anonymity (or, in Cito's case, pseudonymity). If there are people you respect for holding their convictions, did they do likewise?

Comment Re:Well done! (Score 1) 540 540

So, in addition to "affordable" housing, in your ideal world, the poor will also be provided (by someone) with "affordable" Priuses?

Perhaps you've heard of this thing called "transit"?

Which, when done right, gets used by everyone, not just the poor. It was not so long ago a culture shock for me, as a Texan, when my (New-York-based) CEO would take the subway; now, as a transplant to Chicago, I'm very much happier not owning a car at all; my work is a 10-minute walk (hooray for urban high-rise living!), Costco a 20-minute bike ride (hooray for cargo bikes!), my more distant friends in town (or the corporate office, if I need to visit it for some reason) a $2.50, 40-minute train ride, during which my time is free to read, make notes, or otherwise do as I please.

Back to point -- no, setting up your urban environment in such a way that the poor need to drive expensive-to-maintain, expensive-to-fuel vehicles a long distance is not a necessity. Transit systems are subsidized at a higher rate than roads, but not by as much as you might think -- use taxes on highways are under 50% of their costs -- and adding capacity to a roadway system in an urban environment is prohibitively expensive -- particularly compared to adding capacity to preexisting urban rail. And if you look at the economic payoff from that subsidy -- by way of increasing folks' access to jobs -- it's an extremely clear win.

Smart urban planning -- to avoid the need for commutes in the first place by making housing as dense, and nearby to shopping and employment, as possible -- is, of course, even better.

(Back on the "expensive" part of long commutes -- you might find The True Cost of Commuting a worthwhile read, in terms of putting some actual numbers into play).

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