NWS Announces Big Computer Upgrade

riverat1 writes "After being embarrassed when the Europeans did a better job forecasting Sandy than the National Weather Service Congress allocated $25 million ($23.7 after sequestration) in the Sandy relief bill for upgrades to forecasting and supercomputer resources. The NWS announced that their main forecasting computer will be upgraded from the current 213 TeraFlops to 2,600 TFlops by fiscal year 2015, over a twelve-fold increase. The upgrade is expected to increase the horizontal grid scale by a factor of 3 allowing more precise forecasting of local features of weather. The some of the allocated funds will also be used to hire some contract scientists to improve the forecast model physics and enhance the collection and assimilation of data."

Re:so..

[BRock97]

Why not just pay attention to the European forecasts, which would cost nothing?

Actually, the NWS pays a great deal of money to see the ECMWF (the European model of choice) and are required to encrypt it before it is sent out to the various forecast offices over their NOAAPort system.

Re:I would start looking at the algorithms

[Shinobi]

It's not just once. Several hurricanes and other severe weather systems have been most accurately predicted by the European model. In fact, if you read some of the links in the article, you'll see references to that.

Re:I would start looking at the algorithms

[Overunderrated]

With the known chaotic nature of storm systems it wouldn't surprise me if the "butterfly effect" of the rounding errors when converting from C to F would be enough to displace a storm by hundreds of miles!

Absolutely not the case. First, all non-trivial computational fluid dynamics codes (e.g. those used for weather prediction) use non-dimensionalized values in the governing equations. You're not solving with C vs F (you'd never use either anyway, but absolute kelvin vs rankine), or meters vs feet, but non-dimensional numbers which are only converted back to dimensional ones after all the heavy computation is done.

Secondly, even if one were to use dimensional values in solving the equations, the round off errors for converting between C and F are many, many orders of magnitude smaller than the errors you get in the discretization of the original continuous system of equations.

Lots of comments here regarding metric vs. imperial units; I assure you that accuracy discrepancies between the European and American predictions have absolutely nothing whatsoever to do with any choice of unit system.

Source: I'm a CFD researcher =)

Reasons why this is important

[PineHall]

Cliff Mass, University of Washington Atmospheric Sciences Professor, has been arguing for an upgrade [blogspot.com] for a long time. He sees great potential [blogspot.com] for this new system if used right. The reasons [blogspot.com] for the upgrade boil down to having "huge economic and safety benefits" with better forecasting, and he says these benefits are within our reach.

Re:No, Europe had 50 TFLOPS, 1/5th the USA

[ebno-10db]

You're confusing peak and sustained performance. According to the link you provided the latest European system has 70 Tflops sustained performance, but 1.5 Pflops peak. According to this article [theregister.co.uk] the ratings given for the American systems are peak, so the European system is much more powerful than the current US system.