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Comment Some technical info for slashdotters (Score 5, Interesting) 61

I wanted to give some info on the technical aspect of getting this to work that might be appreciated by slashdotters.

You can read about the Blue Waters hardware profile here. Our simulation "only" utilized 20,000 of the approximately 700,000 processing cores on the machine. Blue Waters, like all major supercomputers, runs a Linux kernel tuned for HPC.

The cloud model, CM1, is a hybrid MPI/OpenMP model. Blue Waters has 16 cores (or 32 depending on how you look at it) per node. We have 16 MPI processes going and each MPI rank can access two OpenMP threads. Our decomposition is nothing special, and it works well enough at the scales we are running at.

The simulation produced on the order of 100 TB of raw data. It is easy to produce a lot of data with these simulations - data is saved as 3D floating point arrays and only compresses roughly 2:1 in aggregate form (some types of data compress better than others). I/O is a significant bottleneck for these types of simulations when you save data very frequently, which is necessary for these detailed simulations, and I've spent years working on getting I/O to work sufficiently well so that this kind of simulation and visualization was possible.

The CM1 model is written in Fortran 90/95. The code I wrote to get all the I/O and visualization stuff to work is a combination of C, C++, and Python. The model's raw output format is HDF5, and files are scattered about in a logical way, and I've written a set of tools to interface with the data in a way that greatly simplifies things through an API that accesses the data at a low level but does not require the user to do anything but request data bounded by Cartesian coordinates.

I would have to say the biggest challenge wasn't technical (and the technical challenges are significant), but was physical: Getting a storm to produce one of these types of tornadoes. They are very rare in nature, and this behavior is mirrored in the numerical world. We hope to model more of these so we can draw more general conclusions; a single simulation is compelling, but with sensitivity studies etc. you can really start to do some neat things.

We are now working on publishing the work, which seems to have "passed the sniff test" at the Severe Local Storms conference. It's exciting, and we look forward to really teasing apart some of these interesting processes that show up in the visualizations.

Submission + - Simulated monster EF5 tornado produced by researchers

Orp writes: I am the member of a research team that created a supercell thunderstorm simulation that is getting a lot of attention. Presented at the 27th Annual Severe Local Storms Conference in Madison, Wisconsin, Leigh Orf's talk was produced entirely as high def video and put on youtube shortly after the presentation. In the simulation, the storm's updraft is so strong that it essentially peels rain-cooled air near the surface upwards and into the storms updraft, which appears to play a key role in maintaining the tornado. The simulation was based upon the environment that produced the May 24, 2011 outbreak which included a long-track EF5 tornado near El Reno Oklahoma (not to be confused with the May 31, 2013 EF5 tornado that killed three storm researchers).

Comment Re:They used to be called UHF TV tuners (Score 1) 237

I never did that but a long time ago (80s) I did listen to some fascinating conversations broadcast in the clear around 1.7 MHz - just past the AM band - off of a cordless phone somewhere near my neighborhood. I had an old Hallicrafters shortwave radio that weighed nearly as much as I did (even more with the big external speaker). I don't remember the details of the conversations, only that it was mostly stupid stuff as would be expected.

Comment $150k? (Score 1) 220

I do most of my research on supercomputers. "Servcie Units" (SU's) are the currency on these machines. They are usually either node hours or core hours. Typical allocations are in the hundreds of thousands to millions of SUs.

I don't know what formula they used to come up with a dollar value. It would be nice to know, however, as I am in academia where real dollar grants get all the attention since they come with that sweet overhead. I'm sure my dean would appreciate the symbolism of getting the college overhead in SU's (and converting them to dollars).

But seriously, these machines are up 24/7 (unless down for hardware fault or maintenance) and while I'm sure they draw more current when the CPU is pegged if this guy was mining bitcoins with his allocation then really all he did was go against the terms of his allocation. Those SUs would have either been wasted or used up anyway. But you just don't mine bitcoin on federal supercomputers, man. Dick move.

I hope he at least used GPU accelerators with his code, the bastard.

Comment Hate Variable Air Contraption (Score 1) 216

I have had an office in three different buildings on campus of my university. The first office was fine. I had a situation in the second building where the noise was in violation of Eurpoean Union standards for noise (I had the level measured with a SPL meter) but a couple of dB too low for OSHA. It was maddening; for months I begged facilities to address the issue. The office suite I was in had been converted from a lecture hall and there was this major HVAC hub above my desk, and it turned out they had the pressure way to high flowing through the vents. I wore earplugs a lot.

In the third building I am in, I have a situation where the temperature fluctuates about 15 degrees F daily. Yes, I measured this and plotted it with a little weather tracker. In this case, the thermostat for the office is located in another office. And the university spent hundreds of thousands of dollars to renovate this old building. I guess that's what happens when you always take the lowest bidder.

I am rather sensitive to noise so I'd rather have the fluctuation temperatures in a quiet office than pleasant temperatures in a noisy office, and I understand that when you remodel you might get weird results like this. But that doesn't stop me from wanting to strangle people.

Comment Re:Does anyone even use Google's office suite? (Score 3, Informative) 89

I use it for "simple" stuff - for instance, it's very convenient to have a place to take notes at meetings (I do a lot of that with my job). Since I always have wifi where I work it's just a matter of opening up the Drive website and creating a new document. And then everything's in one place and it's easy to find stuff with Google's search, which works on document names and document contents.

I do create some "production quality" documents from within the Docs world, and export them to PDF or DOCX so I can share. But these documents are generally simple; the complex stuff I do in LaTeX. I really do not like Word with its seven thousand ways to frustrate me and the weird layout that I've never really gotten used to since they majorly changed it years ago. Libreoffice and Google's docs editor are nice and relatively simple and I find them easier to use. But I go back to Word when I have to which is frequently since "everyone" seems to use it.

It's convenient to have the ability to open attachments (from Gmail) in Drive/docs for quick viewing, but stuff created in Microsoft's Office doesn't always convert very well.

I fully realize what Google is doing by "sucking me in" to their world and having everything I do be stored on their servers. Ever since I bought a Chromebook Pixel and got the 1 TB of Drive space, I'm always finding ways to use it. I know they just want to harvest everything I do - so for the sensitive stuff I have an encrypted (ecryptfs) partition with Dropbox that I can mount on my Linux machines, and for wholesale archival storage of sensitive stuff I use PGP and stick it wherever. If Google Drive allowed the ability to mount the drive partition under Linux like Dropbox does, I would probably "drop the box" altogether.

Comment The Why (is obvious) (Score 1) 2219

If you want to know "why" do a Google Trends search on slashdot. You see something that looks like e^-x, asymptoting towards zero.

It's pretty bloody obvious what's going on. A company has a unique asset, this asset is not making them money. I can sort of sympathize with this. You gotta pay the bills, right? So they try to broaden their audience (no quotations, I get that too). But as all the old timers have said - repeatedly - they only come to the site for the comments, and WE ARE THE MOTHERFUCKING COMMENTS. This has to drive marketing nuts, I suppose. There are a bunch of other more "fun" sites out there where idiots can blather on about crap. Slashdot is unique in that it has a highly technical/educated audience and a good moderation system (hah, I remember the uproar over the current comment system when it first came out, or was tweaked - somehow people DO get used to these things!).

I think the reason why you're not seeing Dice or whoever ask for the opinion of the current folks who use slashdot, is that they already know the answer. It's not about you/us - it's about getting new people on board. The problem is, that is a losing proposition. Slashdot's readership/writership really goes back to the USENET days of absolutely no moderation and a has a free-for-all meritocracy mentality. Slashdot has been around for long enough that I think your audience has already found you. We're already here. We are middle-aged highly educated highly opinionated nerds who have dealt with enough corporate horseshit to see through these things. Sorry about that.

There is a pretty high level of childish vitriol that permeates this site. If you don't at least throw us a few crumbs a lot of the crap that goes on at -1 will get a hell of a lot worse. Your audience will turn against you and that will drive away the folks who make the site work. There are alternatives. Christ, with the dwindling number of commenters, you could probably host a slashdot-like site on any of the many cloud server type places out there.

Tread carefully, corporate folks. And it wouldn't hurt if you just accepted the fact that slashdot isn't something that's going to make you money. Maybe you can leverage slashdot in other ways to sell other stuff, I don't know. But if you fuck with your nerdbase they will fuck with you twice as hard. I don't envy your position and I truly hope you find a solution that meets your objectives... keeping the old timers happy while injecting a few audience base. But you should probably try a new approach. Have you considered sending out a survey-monkey type thing to gauge exactly what the old timers are willing to concede/put up with rather than just dumping it on us?

Comment Re:Before this turns into a derpfest... (Score 1) 320

His comment sounds like utter bullshit though. You can put all the CO2 in an atmosphere you want. If you don't have solar flux the heat on the surface will be minimal. One good example is Mars. There have been plenty of examples along history of temperatures decreasing by more than .1 or .3 Celsius even when there were no humans on the planet.

Ok Dr. Bagel. You win. I'll go burn my diploma, tell my colleagues at NCAR to eat a bag of dicks, and await your clearly superior intellect to publish that which is something other than 'utter bullshit'.

Since you are clearly an expert on the subject of the sound of bullshit, please, o wise one: Exactly what does utter bullshit sound like? As opposed to just plain bullshit? Do the flies buzz louder?

Comment Re:Not the sun (Score 1) 320

do you realize that the best possible thing to happen to a scientist is for him/her to make a discovery that tosses the widely accepted hypotheses on their head?

You clearly haven't done much research. As one guy used to say science progresses when the last generation dies. That's how fossilized fields become when all the people doing peer review have the same mindset.

Maybe I should have said "successfully publish a discovery" blah blah. If you don't believe that, well, talk to Einstein, Bohr, Watson, Crick, Darwin, etc. etc. etc.

Comment Re:Bios code? (Score 4, Informative) 533

I would probably have to say whatever is the inner loop on the system idle process in windows.

Ding, we have a winner. Not supercomputer code. Sure, supercomputers are... super and all, but the biggest one only has around 1 million processing cores. How many windoze machines are out there, idling away?

Comment Re:Not the sun (Score 4, Insightful) 320

On the other hand the "alarmist" logic is: "we already know the cause of the warming, it is humans saturating the atmosphere with too much CO2, we just need to gather and/or create the evidence to support this theory". That's called inductive logic, and is just as unscientific as what you describe coming from the "denialists".

"Real" science comes from gathering evidence and basing your theories on the evidence gathered. You then determine what it might take to falsify your theory and try as hard as possible to falsify it.

All I see from the "alarmist" camp is people trying to support their theories at all costs, calling things causation where there is barely correlation, and making very little if any effort to falsify their theories. This behavior is more akin to religion than any sort of science.

False equivalency is false.

Guess what? A lot of the "alarmist" are the same scientists doing the research. Sure, people get attached to theories, but do you realize that the best possible thing to happen to a scientist is for him/her to make a discovery that tosses the widely accepted hypotheses on their head? In other words, if a scientist did a rigorously peer reviewed study which indicated that, say, it's a reduction in neutrinos from the sun somehow, oh, say tweaking aerosol concentrations, leading to a strong causal relationship between this phenomenon and observed global warming - while also showing that the greenhouse effect of CO2 was much less of a factor than previously thought - that person would be fricking king of the scientific world.

The tired repeated bleatings of non-scientists who have not spent their careers repeatedly getting their work shredded by reviewers [this being the norm, not the exception] on the path to eventual publication do absolutely zilch to move things forward regarding understand what's really going on. The simple-minded idea that climate science is some sort of "alarmists versus skeptics" battle is laughable; this false equivalency between two imagined camps, each claiming to know the truth, is entirely imagined by ignorant people. Unless you've actually done science and gotten your work published in decent journals, these opinions mean absolute diddlyshit; nothing more than mental masturbation splooging text on the screen, masquerading as informed debate.

Comment Before this turns into a derpfest... (Score 5, Informative) 320

The NCAR link is probably the best for relating this to climate change:

So could a lengthy drop in solar output be enough to counteract human-caused climate change? Recent studies at NCAR and elsewhere have estimated that the total global cooling effect to be expected from reduced TSI during a grand minimum such as Maunder might be in the range of 0.1 to 0.3 Celsius (0.18 to 0.54 Fahrenheit). A 2013 study confirms the findings. This compares to an expected warming effect of 3.0C (5.4F) or more by 2100 due to greenhouse gas emissions. In other words, even a grand solar minimum might only be enough to offset one decade of global warming. Moreover, since greenhouse gases linger in the atmosphere, the impacts of those added gases would continue after the end of any grand minimum.

So perhaps a serious lull in solar activity could put some feeble brakes on global warming, slowing it down... temporarily, only to charge back when the sun gets over its issues.

I'm a meteorologist, not a climate guy, but I find the hypothesis that the current solar lull is responsible for the recent cold snaps in the northern hemisphere to be extremely dubious. Much more tenuous than the hypothesis that the meandering jet stream is happening due to the reduction in the north/south temperature gradient due from a reduction of Arctic ice cover, which itself is physically feasible but still not shown very conclusively.

The best way to get a grip on these issues would be to run many, many ensembles of weather models and coaxing out statistical links. And this is where weather/climate modeling is going, for good reasons... but as all the armchair slashdot climatologists will (perhaps rightly) point out, models have issues... but they are getting much better and ensembles help a lot to provide a handle on the probability that forcing A is causing response B.

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