Climateprediction.net Data Curation

University of Oxford

Department of Atmospheric Physics

Oxford e-Research Centre

climateprediction.net

The Method: Invite the public to download a full resolution,

3D climate model and run it locally on their PC.

Use each PC to run a single member of a massive, perturbed physics ensemble.

Provide visualization software and educational packages to maintain interest and facilitate school and undergraduate projects etc.

The Goals: To harness the power of idle home and

business PCs to help forecast the climate of the 21st century.

To improve public understanding of the nature of uncertainty in climate prediction.

climateprediction.net

Processing Power

SETI@home peak with 500K users about 1 PF = 1000 TF

climateprediction.net (CPDN) running at about 50 TF (50K concurrent users each 1GF machine average, i.e. P.IV 2GHz conservatively rated)

For comparison, Earth Sim in Yokohama = 35TF max.

BBC Climate Change Experiment

• http://www.bbc.co.uk/climatechange• Participants download a 160-year atmosphere-ocean

coupled model experiment (1920 to 2080)• Promoted as part of the BBC “Climate Chaos” season of

programmes & documentaries• The “Meltdown” documentary featured the CPDN

project and launched the BBC/CPDN experiment in February of 2006

• Started as a BBC4 production but due to popularity ended up being shown on BBC1 with ~2 million viewers

• Still has a strong user community and participant base• Results show broadcast January ’07, presented by

David Attenborough

climateprediction.net

climateprediction.net Users Worldwide>300,000 users total (90% MS Windows): ~50,000 active~20 million model-years simulated (as of February ‘07)

~200,000 completed simulations

The world's largest climate modelling supercomputer!(NB: a black dot is one or more computers running climateprediction.net)

climateprediction.net Screensavers

Results so far…

CPDN / BOINC Server Setup Database Server – Dell PowerEdge 6850,

two Xeon 2.4GHz CPUs, 3GB RAM, 70GB SCSI RAID10 array (RAID5 originally on this former Oracle server, but seems sluggish for mySQL).

Scheduler/Web Server – Dell PowerEdge 6850, two Xeon 2.4GHz CPU, 1GB RAM, also usually <<1%

Upload Servers – federated worldwide, donated, so vary from “off the shelf” PCs to shared space on a large Linux cluster.

Thanks to Paul Jeffreys & OUCS for hosting us gratis over the years, and to Steven Young for much support

NB – we are also now in a “proper” rack (unlike below) thanks to David Wallom!

Data collation & distribution

Data generation

• Per climate model:• 160x “trickle” files, ~67k each, total ~11MB.• 16x “upload” files, ~5MB each, total ~80MB.

• In total• 6696 completed runs to date, ~610GB.• Database backend ~40 GB.• Code, websites &c. ~100MB.

D. A. Stainforth, T. Aina, C. Christensen, M. Collins, N. Faull, D. J. Frame, J. A. Kettleborough, S. Knight, A. Martin, J. M. Murphy, C. Piani, D. Sexton, L. A. Smith, R. A. Spicer, A. J. Thorpe & M. R. Allen, Uncertainty in predictions of the climate response to rising levels of greenhouse gases, Nature, 433, pp.403-406, 27/01/2005

D. J. Frame, B. B. B. Booth, J. A. Kettleborough, D. A. Stainforth, J. M. Gregory, M. Collins, and M. R. Allen, Constraining climate forecasts: The role of prior assumptions, Geophysical Review Letters, 32, L09702, May 2005.

C. Piani, D. J. Frame, D. A. Stainforth, and M. R. Allen, Constraints on climate change from a multi-thousand member ensemble of simulations, Geophysical Review Letters, 32, L23825, December 2005.

G.C. Hegerl, T.J. Crowley, W.T. Hyde and D. J. Frame, Climate sensitivity constrained by temperature reconstructions over the past seven centuries, Nature, 440, p1029-1032, April 2006.

Allen, M., N. Andronova, B. Booth, S. Dessai, D. Frame, C. Forest, J. Gregory, G. Hegerl, R. Knutti, C. Piani, D. Sexton, D. Stainforth, 2006, Observational constraints on climate sensitivity, in Avoiding Dangerous Climate Change, (Eds.) J.S. Schellnhuber, W. Cramer, N. Nakicenovic, T.M.L. Wigley, G. Yohe., Cambridge Univ. Press.PDF of complete book (17 MB), see chapter 29

Knutti, R., G.A. Meehl, M.R. Allen and D. A. Stainforth, Constraining climate sensitivity from the seasonal cycle in surface temperature, Journal of Climate, in press

Designing a Runtime System for Volunteer Computing, David P. Anderson, Carl Christensen and Bruce Allen, To appear in Supercomputing ’06 (the International Conference for High Performance Computing, Networking, Storage and Analysis), Tampa, Florida, USA, November 2006.

N. Massey, T. Aina, M. Allen, C. Christensen, D. Frame, D. Goodman, J. Kettleborough, A. Martin, S. Pascoe and D. Stainforth, Data access and analysis with distributed federated data servers in climateprediction.net , Advances in Geosciences, 8, p49-56, 2006.

Carl Christensen, Tolu Aina, David Stainforth, The Challenge of Volunteer Computing With Lengthy Climate Modelling Simulations, Proceedings of the 1st IEEE Conference on e-Science and Grid Computing, Melbourne, Australia, 5-8 Dec 2005

David Stainforth, Andrew Martin, Andrew Simpson, Carl Christensen, Jamie Kettleborough, Tolu Aina, and Myles Allen, Security Principles for Public-Resource Modeling Research, Proceedings of the 13th IEEE Conference on Enabling Grid Technologies (ENTGRID), Modena, Italy, June 2004

climateprediction.net Recent Publications