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ulenz · Sep 19, 2005, 11:54 AM

PowerMacs G5 for climate simulation needed

The destruction of New Orleans by hurricane has shown the importance of climate for life on our planet. The distributed-computing-project "www.climateprediction.net" tries to explore our climate and its changes in the near future.

Sulphates act to scatter solar radiation and reduce the amount of solar energy reaching the surface. The reduction in solar radiation cools the surface and reduces the warming effect caused by greenhouse gases. So, a prediction of the climate in the 21st century needs to contain the effects of sulphate aerosol. Otherwise the warming trend may be overestimated. This is called the 'global dimming' effect. Therefore the Oxford university in Great Britain created a special "sulphur cycle experiment" within the "climateprediction"-project.

From this experiment it is hoped that scientists will be able to better understand the range of uncertainty in climate models due to the parameters in the sulphur cycle. This information will then be used in the following experiments of climateprediction.net.

The project has just released a special MacOSX-client for the "sulphur cycle experiment", which is very crunch-intensive and needs powerful Macs in order to be completed successfully. On a P4 3.0 in Linux, running stand-alone, one Sulphur Cycle Model requires approximately 39 days (@24/7). Therefore exspect an uptime of 35 up to 60 days for a PowerMac G5 to complete just one Sulphur cycle model. Moreover you will need a quick internet connection to do the upload and download of project files.
Exspect about one gigabyte datas to be downloaded on your harddisk during the whole run and about 20 megabytes datas which have to be uploaded. The datas of the experiment will need up to three gigabytes volume on your harddisk.

This is only a job for powerusers who want to demonstrate the power of the most modern Apple technology and their real interest in the future of mankind.

http://www.climateprediction.net/newsb.php?id=0

mikkyo · Sep 19, 2005, 06:28 PM

They should include a free hard disk with the client

ulenz · Sep 19, 2005, 11:30 PM

I am member of "Team Picard". I bet that we will complete more sulphur cycle models than your team MacNN.

mikkyo · Sep 20, 2005, 12:15 AM

I see your bet and raise you that you will far exceed the zero sulphur models that I complete as well.

reader50 · Sep 20, 2005, 01:16 AM

Now, now.

My BOINC benchmarking efforts will presently involve some Climate models. But my system is a G4, and it might not draw a sulphur model.

ulenz, welcome to our forums. Have a complimentary drink at the bar. Then tell us where it is, we're still looking.

mikkyo · Sep 20, 2005, 03:02 AM

The only bar is in Ten Forward, so you'll have to beam over to their ship to get there and, I hear they take your hard earned project credits while your on board.

siliconman · Sep 20, 2005, 08:30 AM

Originally Posted by mikkyo

The only bar is in Ten Forward, so you'll have to beam over to their ship to get there and, I hear they take your hard earned project credits while your on board.

Now we know you're not a TNG fan. Ten Forward is only one of many bars on the enterprise. It just happens to be more popular because of the view.

Knightrider · Sep 21, 2005, 10:02 AM

Had a problem downloading the sulpher model.

Please follow this link to the CPDN problem pages for details.

http://climateapps2.oucs.ox.ac.uk/cp...ad.php?id=3227

K.

ulenz · Sep 21, 2005, 12:18 PM

Reset the project and try again. The problem is, that this model simulates about 200 years and is very complicated inside. Therefore it seems to be improved steadily based on the upload results of the models which have crashed so far. As long as the model runs you will get credit.

Knightrider · Sep 21, 2005, 03:38 PM

Originally Posted by ulenz

Reset the project and try again. The problem is, that this model simulates about 200 years and is very complicated inside. Therefore it seems to be improved steadily based on the upload results of the models which have crashed so far. As long as the model runs you will get credit.

Hi Ulenz - Tried that a couple of times,but it will not all download.

K.

ulenz · Sep 21, 2005, 11:55 PM

Okay, I had that problem too, but since yesterday morning a new sulphur experiment is trickling again on my PowerMac G 5 1,8 Ghz Single. It's a little bit frustrating that there are certain download- and crashing problems with the sulphur cycle model until now. On the other hand nobody promised us that scientific research is an easy job to do. "Where boldly no one has gone before......", this is a fact for that very exclusive experiment. It's not a job for the "heart-fainted", therefore "Starfleet's computer department" has to do it at any costs.

Cluster · 09:58 AM

im running the sulphur model 4.21 on my Mac Mini 1.42ghz G4 and have no stability problems, in fact i have not turned the little machine of since i got it back when they first came out.

The model dose take a long time to complete (3339 hours around 80 days) but i am confident that it will complete before the deadline in Feb.

So G4 Users, done be put off, If you have a prcessor over 1Ghz and keep your mac on all the time, why not let it chew through the sulphur cycle at CPN, its a very worth while project.

CPN Total Credit 150897.19
Avg. Credit 675.48