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Comment Re:aren't these aimed to prevent not detect? (Score 1) 151

"Finds its way in"? You may have noticed that the folks behind the French attack were born there.

As a society, France isn't doing a very good job of helping immigrants feel like Frenchman -- even two or three generations out. Meaning you get folks who feel like second-class citizens, easy to radicalize and recruit.

And, for that matter, the US has no small problem with homegrown terrorism either. Hello, Oklahoma City bombing. Hello, burning churches. Looking at terrorism as a problem that comes from outside is understating the issue.

Comment Re:Yes, you've increased the precision (Score 1) 89

You may turn CP off but you're sure as hell still parameterizing (microphysics!! And just how many choices do you have for those fun knobs!). And 4km is still pretty damned coarse for thunderstorms. But yeah there is clearly more to surface wind intensity than eyewall replacement, that's just an example of something that is thought to play a role and that is definitely handled better with finer meshes (tropical is not my expertise).

We're doing much better, but we've still got a lot of work to do to get hurricanes right - some of it is with the models, some of it (more, in my opinion) has to do with what we feed the models. Hoping GOES R will be a big help. Pray for a launch that doesn't blow up on the launchpad.

Good riddance to cumulus parameterization, when that day comes in everything but climate models (let's not get too carried away) I will dance with glee on reams of printouts of CP code. Microphysics is a big enough kludge but I don't think we're going to be following raindrops and snowlfakes around in our models for a long, long time.

Comment Re:Yes, you've increased the precision (Score 1) 89

The path of a hurricane is somewhat unpredictable (been known to turn 90 degrees for no apparent reason).

We've gotten much better at predicting the paths of hurricanes which are, to a first degree of approximation, steered by larger-scale winds that have gotten easier to predict with time because of improved observational data feeding models, as well as the fact that they are easier to resolve and are dictated by things that don't require lots of parameterization (like what you have with convective clouds and precipitation). What we continue to struggle with is the strength of the surface winds over time, which of course is highly desired at landfall. There are small scale processes going on within hurricanes (involving what meteorologists call eyewall replacement cycles) that modulate surface winds and that are less understood and much more difficult to forecast correctly. Basically, the smaller it is, the harder it is to forecast over long time periods.

If I had to choose between getting one or the other right, though, I'll choose path over surface wind strength. Getting out of the way of a Category 2 vs getting out of the way of a Category 5 is pretty much the same process!

Comment Re:So what (Score 1) 44

You might try actually looking at some faces for the 360. Hint: They're still centered on the middle of the physical display. Looking at my wrist right now, it's 27 minutes after the hour and all that's cut off is some of the dashes marking minutes; the hand itself is still on-screen, but I expect that at 1:30 proper a few pixels for the edge of that hand might be cut off.

And, y'know what? I can't say that disturbs me overmuch. If (as they claim) this design feature avoids the need for a larger bezel while allowing an accurate light-level sensor, I'll keep it.

[At the end of typing the post, it's :30 after; looking at my wrist, the very tip of the minute hand is indeed occluded -- which answers your prior claims: No dead space, no distortion].

Comment Bottled ink and fountain pens (Score 1) 223

I'd be curious to see if any of the low-cost ink manufacturers for fountain pen ink branch into inkjets, with this development. Both being water-based and having constraints around lubrication, flow, penetration, dry time, etc., I wouldn't be surprised if there were a fair bit of room for knowledge (and chemistry R&D, for a shop with a wide enough range of ink properties) to translate.

Buying bottled ink is already the cost-effective option for folks writing the old-fashioned way -- the equivalent to a sub-$20 4.5oz bottle of waterproof fountain pen ink (current price for a large bottle of Noodler's Heart of Darkness, 8/4/2015, is $19) would, if purchased in rollerball refills, be in the range of 76 to 82 pen refills, priced from $1.66 to $3.20 each; going the bottled route is vastly saner for folks who are willing to buy several years' worth of ink at one go.

(Up-front costs to use bottled ink aren't that high either -- excellent sub-$30 pens include the TWSBI Eco, Pilot Metropolitan and Lamy Vista).

But then -- with an extra-expensive printer, perhaps simply voiding the warranty if someone used a competing ink would be enough to prevent customers from trying to cut costs there. Hmm.

Comment Re:Likely a new gift for the NSA (Score 2) 223

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) 223

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) 223

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


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) 223

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

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

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

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. :)

SCCS, the source motel! Programs check in and never check out! -- Ken Thompson