Last week's issue of Nature was about climate change. It included two letters, Greenhouse-gas emission targets for limiting global warming to 2 °C and Warming caused by cumulative carbon emissions towards the trillionth tonne, which CPDN researchers contributed to.

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Cpdn news

Mac users on the CPDN main project

If you are running CPDN on a Mac you might find that tasks from some version 6 applications are crashing immediately.

The HADCM3 and HADAM3P applications had to be compiled with the latest Fortran compiler, all other applications were compiled with the previous version. A Fortran dynamic library has to be re-distributed with Mac applications, with a different version being required for the 2 compilers. But the files have the same name, which creates an unavoidable conflict:

• if the first CPDN task you download is not HADCM3 or HADAM3P you'll only be able to run tasks for the HADSM3, HADAM3 and HADSM3 Mid-Holocene applications.
  
  
• if the first CPDN task you download is HADCM3 or HADAM3P it's possible that you'll only be able to run those applications.
  

Tolu is working on resolving this, but in the meantime your best option is to modify your project preferences to exclude the applications you are having problems with.

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"The ultimate test of a moral society is the kind of world that it leaves to its children." - Dietrich Bonhoeffer

BBC Climate Change Experiment

The BBC CCE project is being shut down. All models which are still running will be sent a killer trickle next time they send a message to the scheduler and you should not attempt to restore from backup. The scheduler and upload servers will be disabled at the end of this week and you will not be able to return any more trickles or upload files after that happens.

The results which have been returned will be used as part of a submission to the IPCC AR5 (Intergovernmental Panel on Climate Change Fifth Assessment Report). Carl Christensen is working part-time for CPDN on this and is adapting the model to collect some further data for the submission. This will be released on the main CPDN project.

Any BBC CCE users who have yet to sign up for the main project should follow the instructions here

This may be of interest to Facebook users who have not previously joined Boinc (since you are already a Boinc user then I would recommend keeping your existing setup, unless you want to start using the Grid Republic account manager).

Progress Thru Processors announcement
\"John Cooney\" wrote:

My name is John Cooney and I am a project lead at Intel. I wanted to share with the BOINC community a project that we are about to launch called Progress Thru Processors.

Intel is sponsoring Progress Thru Processors which is a Facebook application developed in association with GridRepublic and BOINC. Progress Thru Processors will feature Rosetta@home, Climateprediction.net and Africa@home (malariacontrol.net), but participants are not required to join these, and can add any BOINC project once the application is added to their profile.

Intel has been a supporter of volunteer computing for many years, dating back to SETI@home. We felt that by combining the networking power of Facebook with the promise of volunteer computing we could attract large numbers of new participants many of whom may never have even heard about volunteer computing.

In support of the project, the BOINC team is adding some interesting new features to the client, including an automatic proxy detection system which, when finished, will allow Intel employees and others within corporate IT environments to more easily participate in volunteer computing on their work PCs.

Our plan is to launch a public beta version on Monday, but I would like to share early access to the application with people in this forum. We hope you\'ll enjoy it; please do let us know what you think.
http://apps.facebook.com/processors/new.php

Thanks,

John Cooney
Intel Corporation

As far as existing Boinc users is concerned, all it appears to do is sign you up to the Grid Republic account manager.

Discussion thread

What model names mean

For example in the case of hadam3p_n8u2_1973_2_006090300_3_1.zip:

hadam3p = model type
n8u2 = batch identifier
1973 = model start year
_2_ = number of model years to be crunched
006090300 = model number for the whole workunit
_3 = iteration number for this particular task
_1.zip = file number (not really part of the task name)

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Cpdn news

The online magazine International Science Grid This Week has published an article called How green is my grid? which mentions the role of CPDN.

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Cpdn news

CPDN credits

Credits for each completed model type have been increased as follows and also retroactively:

• HadAM3 was 5,184.00, now 5,443.20, +5%
  
• HadAM3P was 1,982.64, now 2,081.77, +5%
  
• HadCM3 (80 year) was 24,883.20, now 26,127, +5%
  
• HadCM3 (160 year) was 49,766.40, now 52,254.72, +5%
  
• HadSM3 was 6,805.26, now 7,145.52, +5%
  
• HadSM3MH was 9,073.68, now 9,527.36, +5%
  

Credits per trickle will of course also increase by 5%.

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Cpdn news

Carl Christensen of cpdn and QCN (Quake Catcher Network) fame recently gave an informative presentation on Volunteer Computing In The Earth Sciences at the London Institute of Physics. (Link points to a the PowerPoint 2007 presentation)

CPDN applications are 32bit. Some 64bit Linux distributions do not have 32bit compatibility libraries installed by default. In order to run cpdn on a 64bit Linux distribution without errors, you may have to install these compatibility libraries. See this entry in the BOINC wiki for more information.

Myles Allen, CPDN\'s chief researcher, has given an update on current experiments to Milo. Here it is:

Dear all,

Here is a long-promised update on the experiments we are writing up, running or preparing for release, with apologies for not having kept everyone in the loop. First, a status update on the experiments we have already released, in more-or-less chronological order of release:

1) The original slab experiment. This continues to provide grist for doctoral theses and detailed studies of how the atmosphere in the Met Office model responds to parameter perturbations. An ongoing debate is whether it is possible to generate the very high responses to doubling carbon dioxide that were reported in Stainforth et al without rendering the climate of the model demonstrably unrealistic. The original “11oC” models were, with the benefit of considerable hindsight and additional scrutiny, relatively unrealistic, but plenty of models have now been found that generate these high sensitivities through different mechanisms (indeed, the main result of that whole experiment was how easy it turns out to be to increase the sensitivity of this model to alarmingly high levels), and we are sending out targeted work-units to explore these in more detail.

2) The BBC Climate Change Experiment / climateprediction.net transient ensemble. Dave [Frame] has the main results of this experiment now written up, and it’s on my desk for editing (sorry, Dave), so we hope to submit that paper soon. It’s taken a while, because we’ve been having to develop a whole new approach to analyzing coupled model ensembles as we go along. It’ll have been worth the wait. There are still gaps in parameter space that we want to fill in on this experiment, so we are still sending out these coupled work-units as these are identified.

3) Pardeep Pall’s seasonal attribution experiment is written up and on my desk for editing (sorry, Pardeep).

4) Neil Massey’s study of extreme weather events has completed its first stage (simulation of 1950-2000), which he is writing up for his thesis, and will shortly be distributing work-units for 2000-2008 – this one feeds directly into Jara Imbers’ experiment (see below).

5) Kate Ricke’s geo-engineering experiment. This is now written up and submitted for publication, and she has some ideas for follow-up runs.

6) Falk Niederhorst’s study of climate predictability, based on the slab experiment, is in progress.

Those are the experiments that we have released through the main climateprediction.net site. We now get onto the experiments we have in beta release or still in preparation.

7) William Ingram’s transient ensemble for the IPCC Fifth Assessment. Lots of people are contributing to this experiment, but we’ve asked William to coordinate it, so I’m using that title as short-hand. This follows essentially the same format as the BBC Climate Change Experiment but with an updated model, allowing a wider range of perturbations to be explored, updated climate drivers (projected greenhouse gas levels and the like) to be consistent with the drivers used by the major modeling groups in the so-called “CMIP-5” model inter-comparison, and an updated design: we are now running from 1880-2120 split up into 40-year work-units rather than single 1920-2080 160-year work-units, which none of you liked because they took so long to finish. It has been a fair amount of work for Tolu making this possible, but now he has done it, we will be able to target work-units much more flexibly in the future. This is a multi-stage experiment:
a. Ocean spin-ups, completed last year through the beta site.
b. Atmosphere spin-ups (40-year work-units to compute the surface fluxes associated with perturbed atmospheres), currently under distribution through the beta site.
c. Coupled control work-units, which have the same drivers as the spin-ups (a simulation of average climate conditions in the late 19th century), run to check the model’s stability. We aim to start distributing these soon through the beta site.
d. Coupled transient work-units, which contain the drivers for simulating 1880-2120, which we hope to be distributing by the end of the year (we are checking the driver files very carefully).

We will, of course, be using results from the existing BBC Climate Change Experiment to target these runs, so we should be able to explore both parameter space and climate driver uncertainty more comprehensively this time. One of the main criticisms often leveled at the CMIP model inter-comparisons is that, to allow all the modeling groups to run the simulations, they only explore a very restricted ranges of scenarios for future emissions. We can explore a much wider range, to put the CMIP-5 results into context.

8 ) Jara Imbers’ extension of Neil Massey’s experiment. Neil has been running an atmosphere-only model driven with prescribed sea-surface-temperatures which allows higher resolution and shorter work-units. Jara is extending at least a few decades into the future now that we have a range of simulated surface temperature changes from the various coupled experiments (both our own and other peoples) to draw on. This isn’t entirely straightforward, to put it mildly, mostly because of complications with how to make the sea-ice consistent with the surface temperatures (in the coupled models, sea-ice is computed, so while it might be wrong, it is at least self-consistent), but it does provide a way of getting substantially higher atmospheric resolution than is possible in the coupled experiments, which is valuable for impact studies. The software for this experiment already exists (it is identical to Neil’s), but we are working on the driver files.

9) Hiro Yamazaki’s MILLENNIUM experiment. This follows the same format as the BBC Climate Change Experiment but uses a faster model (with a lower-resolution atmosphere) to simulate climate change over the past millennium. The longer time-scales should provide a much stronger constraint on climate change over the next couple of centuries. Hiro is aiming to get this on general release by the end of the year.

Finally, our most ambitious experiments under preparation involve the use of the embedded regional model to give substantially enhanced resolution in selected regions for climate impact studies. These will provide a unique way of simulating realistic weather for a wide range of possible climate changes, which will be invaluable for planning adaptation strategies. This is also a perfect application of distributed computing, because of the large ensembles required to generate adequate weather statistics. There are plenty of other groups around the world looking at this problem, but they are all hampered by not being able to run ensembles as large as they would like to, and hence have to resort to complicated statistical post-processing to try and estimate what they would have found if they had been able to. We feel (and plenty of people agree with us) that it is much better as a general rule to provide climate impact assessments with actual climate model output rather than simulated output from a statistical model, because this ensures that the fields provided are internally consistent (that is, satisfy the laws of physics). We are taking two complementary approaches based on the experiments we have already performed, both funded largely by Microsoft Technical Computing:

10) The coupled regional climate modeling experiment, led by Richard Jones at the Met Office. In this experiment we embed the regional model HadRM3 directly into the coupled atmosphere-ocean model HadCM3L, to simulate regional climate change directly for selected 5-year periods within the coupled transient ensemble. This builds on an 11-member ensemble performed with this set-up for the UKCP09 Climate Projections project. So far, we have been testing a domain located over Southern Africa at 50-km resolution and a domain located over the Pacific Northwest at 25-km resolution. As many of the beta-testers will know, the Pacific Northwest domain has been giving trouble, which may simply result from that specific choice of domain and resolution, in which case fixing it will simply be a (tedious but straightforward) matter of varying the domain until we find something that works. Or it may also indicate a bug, which clearly we would want to track down before releasing this experiment. Given these problems, we have decided to release another experiment in parallel.

11) The atmosphere-only regional climate modeling experiment. This is a straightforward synthesis of Neil and Jara’s atmosphere-only experiments with the coupled regional modeling experiment, in which we embed the regional model into the higher-resolution HadAM3P model rather than into HadCM3L. The lower contrast in resolution between the driver atmospheric model and the regional model may help make this setup more stable (it has certainly been used very successfully under the Met Office PRECIS project), but time will tell. This is still under preparation, but given it is substantially simpler than the coupled regional modeling experiment, it may end up getting released first. It remains an open question which is the better experimental design: running an atmosphere-only model in so-called “time-slice” mode allows for higher global atmospheric resolution, which improves the simulation of the circulation driving the regional model, while running the regional model directly embedded in the coupled model allows atmosphere-ocean interactions to be simulated more faithfully. When a question is open like this, the best option is to try both approaches which, with your help, we will.

Once again, none of these experiments would be possible without our participants’ support: thank you all again, and please keep modeling.

Myles

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Cpdn news

CPDN\'s chief scientist, Myles Allen, was mentioned in this Financial Times article.

Myles, Dave Frame also of Oxford University and Charles Mason of the University of Wyoming have published an article called The case for mandatory sequestration in Nature.

You may wish to see how much CO2 we\'ve already emitted on the Oxford University website TrillionthTonne.org.

David Archer who lectures in climate and global warming at the University of Chicago has posted about his current course on the RealClimate website. We can download and watch the course, called Global Warming: Understanding the Forecast. The lectures are very clear but do include some physics and chemistry. One needs Quick Time player. (Not for members with dialup.)

Reminder: Using Boinc and participating in projects such as CPDN is voluntary. We must only crunch on our own computers or those whose owners have given us permission!

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Cpdn news

Sue Rosier, one of CPDN\'s researchers, has just posted on the independent forum:

TODAY at 11:30 a.m. you can watch Myles Allen debating with Darren Johnson on

After Copenhagen: Where to now for the climate debate? at

http://timesonline.typepad.com/science/2009/12/live-debate-after-copenhagen-where-to-now-for-the-climate-debate.html

(And please be aware - Myles has warned he won\'t be talking about the server status!)

That\'s in just 30 minutes. Perhaps the conversation will also be watchable later.

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Cpdn news

\"SueR\" wrote:

A recent article by Myles Allen on SAFE carbon appeared in the Frankfurter Allegemeine Zeitung (7 December).

An English version of the article, which is entitled \'Beware of what you wish for in Copenhagen\', can be found here:

http://climateprediction.net/content/public-presentations-talks-and-posters

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Cpdn news

Reports are starting to appear about the latest version of Norton AV, Sonar, not being happy with cpdn programs.
This is just the latest episode in a long saga of AV programs wrongly detecting a virus.

And the cure is the same as before:
1) Use the menu option to prevent the AV from scanning any of the BOINC folders.
2) Use a different AV. Or at least until Norton has it\'s next update. (Which may or may not fix the problem, and may or may not cause a different one. :( )

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Relevant threads on past problems, in the README files: Crashes and other problems. (The middle of the first section.)

Mentions by crunchers of the latest problem:
Our alternate board
This board
This board

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Backups: Here

Several publications by the ClimatePrediction researchers have been added to the Publications page.

Knutti, R., G.A. Meehl, M.R. Allen and D. A. Stainforth, 2006: Constraining climate sensitivity from the seasonal cycle in surface temperature, Journal of Climate, 19 (17), 4224-4233. A 10-page pdf.

Knutti, R., S.Krähenmann, D. J. Frame and M. R. Allen, 2008: Comment on \'Heat capacity, time constant and sensitivity of Earth\'s climate system\' by S. E. Schwartz, JGR, 113, D15103, doi:10.1029/2007JD009473. A 6-page pdf.

Sanderson, B., R. Knutti, T. Aina, C. Christensen, N. Faull, D. J. Frame, W. J. Ingram, C. Piani, D. A. Stainforth, D. A. Stone and M. R. Allen, 2008: Constraints on model response to greenhouse gas forcing and the role of subgrid scale processes, Journal of Climate, 21, 2384-2400. A 17-page pdf.

H. Fowler, D. Cooley, S. Sain and M. Thurston: Detecting change in UK extreme precipitation using results from the climateprediction.net BBC climate change experiment, 2010, Extremes DOI 10.1007/s10687-010-0101-y.

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Cpdn news

The anti-virus program AVG V9 is causing problems with uploads.

Sticky here
Thread for discussion here

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Backups: Here

A few Millennium models have been added to those available for selection.

These are called FAMOUS, after the program used to run them.
From our Experiments page: Millennium experiment with FAMOUS

PS
I\'ve been running test models for so long that I forget to say:

They run FAST. Once you get some trickles sent back, have a look at it. The red graph along the top shows the various volcano eruptions.
Also have a look at the various plots on your computer, especially in Wall Map view.
The weather just flys across.

No doubt a sticky will be made about them, once what should go into it is thought out.

Update: A bit disappointing for some perhaps, but older computers without SSE2 will crash these models as soon as they start.

Update 2: A newer release of the FAMOUS models doesn't have the SSE2 limitation. If SSE2 isn't available, they now drop back to running without it.

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Backups: Here

FAMOUS is available for Windows, Mac and Linux: here is the Applications page. You can see the number of tasks available for download on the Server status page.

Please note that, as Geophi has posted here, FAMOUS cannot run on computers without SSE2 or SSE3 processor capability. This also applies to HadAM3P as Geophi explained here. You can check your processor features about 8 lines from the top of the computer\'s Boinc manager messages.

For computers that cannot run FAMOUS or HadAM3P you should select only HadSM.

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Cpdn news

Millennium Project FAMOUS models update

The new FAMOUS models will contribute to the European multidisciplinary experiment involving 16 countries and many universities. The Millennium website explains how the climate of the last millennium will be analysed using climate models and proxy data. The CPDN modelling contribution is described here and its lead researcher is Dr Hiro Yamazaki at Oxford University.

The very long FAMOUS models are distributed in 200-year segments each of which at the end generates a restart dump from which the next 200-year period can begin. They are available on all platforms. At the moment the models run very fast, taking fewer than 130 hours on a C2D 6600. A slower version is, however, being beta-tested in order to improve model stability.

A small proportion of these models crash and should not be restored from backup. They would fail again at the same point.

In your account you can look at your computers and their tasks. When a task has completed, successfully or not, on its web page you can click on stderr out to see the Boinc messages. Typical messages that indicate a crash was caused by model (or compilation) instability include:

INVALID THETA DETECTED
NEGATIVE PRESSURE VALUE CREATED
Signal 11 received, exiting...

and in Linux, FAMOUS v.6.01, some less frequent messages:
SIGSEGV: segmentation violation
Signal 2 received, exiting...
Signal 15 received, exiting...

These error messages do not indicate that your computer is unstable.

As well as the globe graphics, Tolu is developing sophisticated graphs which will later become available on models\' web pages.

If you wish to try FAMOUS you can select it in the ClimatePrediction section of your CPDN account.

Please subscribe to this News thread which is where further detailed announcements will be posted.

Reminder: FAMOUS can only run on computers with SSE2 capability. SSE is not sufficient. You can check whether your processor has SSE2 by looking at your Boinc manager messages about 8 lines from the top. This also applies to HadAM3P models. Computers without SSE2 should select HadSM models.

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Cpdn news

Millennium Project FAMOUS update

The following warning about this early stage of the FAMOUS experiment has just been added to the Millennium experiment with FAMOUS page:

The Millennium/Famous experiment uses a radically new way to run perturbed atmosphere-ocean coupled models without dynamic flux adjustments. Therefore, we expect many models to run away quickly from realistic climatic conditions, especially when we perturbed the internal parameters of the model. The main test of such models are performed for the \"spin-up\" period labelled as 599-799 AD. For this period, we don\'t use time-evolving external forcing data. We simply keep them constant to see how each model adjusts to its own new equilibrium. However, since some of our perturbations are fairly strong, many models will simply run away!

Also, we use several extreme forcing scenarios. For example, the largest volcanic eruptions in the last Millennium are estimated to be several times larger than the Pinatubo eruption in 1991. Moreover, to cover the full range of uncertainty in the historical volcanic eruption data, we even try the case with 3 times the best estimate of volcanic forcing.

Once we find a variety of not-outrageous models, we will only use them to run more realistic simulations from 800 AD towards near future. Such runs still include the setup with the extreme scenarios, and some of the models that survived the spin-up period will probably go wild. We also noticed that the current Famous model is perhaps somewhat less stable than other models we have been using. In any event, we compare model\'s outputs with observational data and evaluate the goodness of each model run. The goodness measure will be used to illustrate the range of plausible future.

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"The ultimate test of a moral society is the kind of world that it leaves to its children." - Dietrich Bonhoeffer