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Will H

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Message 7277 - Posted: 13 Jan 2005, 21:54:20 UTC

Did anyone else see Horizon tonight, all I can say is wow!

Have CPDN thought of creating a climate model factoring this in?

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Profile Andrew Hingston
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Message 7278 - Posted: 13 Jan 2005, 22:37:46 UTC - in response to Message 7277.  

&gt; Did anyone else see Horizon tonight, all I can say is wow!
&gt;
&gt; Have CPDN thought of creating a climate model factoring this in?
&gt;

there is a discussion about this <a href="http://www.climateprediction.net/board/viewtopic.php?p=24952#24952">here</a>.

The thesis doesn't really invalidate the CPDN work, but there is an experiment in preparation that factors in the effect of sulphur compounds, which is another of the aspects of fossil fuel burning. Those of us with faster machines should be able to run that experiment in the next month or two, I think.
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old_user415

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Message 7756 - Posted: 27 Jan 2005, 14:29:24 UTC - in response to Message 7278.  

&gt; &gt; Did anyone else see Horizon tonight, all I can say is wow!
&gt; &gt;
&gt; &gt; Have CPDN thought of creating a climate model factoring this in?
&gt; &gt;
&gt;
&gt; there is a discussion about this <a> href="http://www.climateprediction.net/board/viewtopic.php?p=24952#24952"&gt;here</a>.
&gt;
&gt; The thesis doesn't really invalidate the CPDN work, but there is an experiment
&gt; in preparation that factors in the effect of sulphur compounds, which is
&gt; another of the aspects of fossil fuel burning. Those of us with faster
&gt; machines should be able to run that experiment in the next month or two, I
&gt; think.
&gt;
Global dimming certainly doesn't invalidate the CPDN work.

We are indeed very close (two or so months) to launching a new experiment that includes the emission of sulphate aerosols, and their impacts on clouds, both of which contribute to so-called global dimming. In fact "global dimming" is not as new a topic to climate science as Horizon made out - someone just gave it some good marketing. It is however true that it's believed to be important to include aerosols in climate model predictions, particularly those trying to recreate the past 50 years or so. The new experiment will allow us to examine in very great detail what difference including these particles in the atmosphere makes to the model sensitivity to changes in carbon dioxide and to increased emissions of the sulphur compounds themselves. In some small tests we've already seen some interesting things happening to rainfall. Keep an eye on the boards and the website for more information about this experiment in the late Spring.


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Message 7773 - Posted: 27 Jan 2005, 15:37:02 UTC

Thanks for the update on the sulphur cycle experiment, Ellie.
"The ultimate test of a moral society is the kind of world that it leaves to its children." - Dietrich Bonhoeffer
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Message 9352 - Posted: 15 Feb 2005, 12:05:15 UTC - in response to Message 7773.  

Thank you for the information about incorporating these effects in the new models. I just joined and am going to have to wait appr. 60 days to finish my first two runs of the old model. Is there a way to apply for runs of the new model, including these new settings by then?<br />

Because i am especially curious about what will happen if the emissions of these sulphur compounds are to drop while co2 levels keep increasing.<br />
Also, Horizon suggested that Europe caused the cause of live aid with these emissions (draught in the Sahara). Maybe the new model can confirm this?
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Message 9353 - Posted: 15 Feb 2005, 12:26:29 UTC - in response to Message 9352.  

Hi Willem and welcome aboard.

There is an alpha-testing of sulphur model going on. Actually, it is rather a combination of CO2 and Sulphur so effects of both will be possible look at.
My estimation is that sulphur cycle models may be available to participants by the time your models have finished; there are still issues to deal with and test before releasing beta and public version.
In a first stage (e.g. alpha-testing) it is better for the progress of testing that participant familiar with both BOINC and CPDN test those models in order to provide feedback and chase bugs.

&gt; Thank you for the information about incorporating these effects in the new
&gt; models. I just joined and am going to have to wait appr. 60 days to finish my
&gt; first two runs of the old model. Is there a way to apply for runs of the new
&gt; model, including these new settings by then?
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Message 9946 - Posted: 25 Feb 2005, 1:15:07 UTC

re: horizon programme "launching a new experiment that includes the emission of sulphate aerosols, and their impacts on clouds".

Am I missing something here? If you read the transcript of the program over at the bbc website, you'll see it doesn't ever mention sulphates at all in relation to global dimming.

It explains the increasingly reflective cloud effect that causes dimming as being caused by microscopic soot particles and the like over-seeding clouds so that many more smaller droplets are created. The smaller droplets just happen to (through physics apparently) reflect more light.

Sulphates and aerosols are not mentioned in the programme at all. (not once).
Also when following up papers written by contributors to the program, I also did not encounter any mention of aerosols or sulphates. Therefore if you fail to consider the effect of microscopic soot particles seeding the clouds, you aren't really responding to the issues raised in the program about "global dimming".

I just thought I ought to point that out, because this thread looks like a disjoined couple of conversations, like when your mum asks your uncle albert for the sugar, and he says "half past four".

Perhaps I'm missing a logical step here like when an astute mathematician writes "simplifying" and the formula below doesn't appear to match the formula above.



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Message 9954 - Posted: 25 Feb 2005, 2:56:46 UTC

Hi Hipparchus

Not as disjointed as may at first appear. Sulphur compounds were not part of the Horizon programme, but Anrew H quite reasonably wondered about their relevance to global dimming.

At which point Ellie, who must be Dr Eleanor Highgrove at Reading University UK, leading cpdn research there, answered Andrew and updated us on the progress of the cpdn sulphur experiment.

Sorry to have blown your cover, Ellie, but you were on TV yourself recently in the Krakatoa programme.

The whole cpdn project is climatologically wide-ranging, so it is easy for conversations to cover several aspects and change direction, as in real life.
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Message 10031 - Posted: 26 Feb 2005, 2:08:31 UTC

This post makes no pretense at a solution to the flap at hand. I merely ask folks to consider the reflectivity of Venus -- our closest Planet, in terms of distance and size. Venus is chock full of clouds -- and not a few therms.

True, Venus' atmosphere is mostly CO2 and doesn't closely resemble the chemical composition of the (increasingly foul) atmosphere of our home rock. But, somewhere between our formerly life-friendly mix of Nitrogen/Oxygen and the hellish CO2 atmosphere of Venus, there is plenty of space for adding parameters to the Earth-centric Models we run. And to do so without introducing factors/expectations into the discussion not yet introduced into the Project?

Can we give the CPDN Project the time required to evolve according to plan? Without demanding more of it than it could ever hope to provide? A look into the CPDN's raison d'etre and history may well prove instructive.
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Les Bayliss
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Message 10034 - Posted: 26 Feb 2005, 4:33:45 UTC
Last modified: 26 Feb 2005, 4:35:56 UTC

Mo,
Not to criticise, but isn't Ellie the other type of tall vegetation? Wood, not grove?

As for the 'disjointed' appearance of the threads on various parts of this site, it's just the 'cocktail party effect'.

Les
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Message 10090 - Posted: 28 Feb 2005, 1:27:39 UTC
Last modified: 28 Feb 2005, 1:42:27 UTC

You are right, Les, I should have said Ellie Highwood. Sorry again, Ellie!

I have obviously been hearing far too much about the place where Prince Charles hangs out, which I think actually IS called Highgrove, but I am not going to waste time googling that to check it! It's sad, though, that my brain has been hijacked by news of the royals.


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Message 10091 - Posted: 28 Feb 2005, 1:31:36 UTC

Mo,

I don't suppose there is anything on that Krakatoa program on the net somewhere? Got done reading the book Krakatoa right before Christmas and would like to see something more on it as it relates to climate.

George
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Message 10094 - Posted: 28 Feb 2005, 1:56:20 UTC

I think it was on Channel 4 - I'll have a look.

If I'd known that Ellie was going to be on it, I'd have recorded this documentary. Ellie talked about various historical documents, and they also showed several of a series of paintings of the astonishing sunsets that occurred worldwide for at least a year after the explosion. A painter, can't remember the name, systematically painted the sunsets as a record, just as carefully as Monet studying the haystacks.
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Message 10097 - Posted: 28 Feb 2005, 3:31:29 UTC
Last modified: 28 Feb 2005, 4:54:29 UTC

I haven't found a 'watch again' facility, but this page gives lots of background info about the programme and some interesting links, plus a bibliography.

<a href='http://www.channel4.com/science/microsites/S/science/nature/krakatoa.html'>Channel 4</a>



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Message 10100 - Posted: 28 Feb 2005, 7:15:38 UTC - in response to Message 10097.  

&gt; I haven't found a 'watch again' facility, but this page gives lots of background info about the programme and some interesting links, plus a bibliography.
&gt;
&gt; <a href='http://www.channel4.com/science/microsites/S/science/nature/krakatoa.html'>Channel 4</a>


Do we need a barcodes on each article? That's the production...

quote: At sunset, the sky turned an incredible fiery red and orange colour as far away as London, as depicted in the paintings of William Ascroft. It's estimated that over 70% of Earth's atmosphere was impregnated with the remains of Krakatoa, so much so that the average global temperature cooled by half a degree Celsius.

Nice reading, anyway.
<i>phpBB forum for CPDN, all are </i><a href="http://www.climateprediction.net/board">invited</a>
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