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Posts by old_user55255

Posts by old_user55255

1) Message boards : climateprediction.net Science : June Snow on the USA Gulf Coast (Message 11170)
Posted 20 Mar 2005 by Profile old_user55255
Post:
> Eric, did you see my post a few weeks ago in another thread about your
> east-to-west winds? I'm sure I was right about all that from the point of view
> of normal climate patterns, but from the temp displacement above, which I can
> now see clearly, it looks as if there may be several strange things going on
> here.
>

I'm talking about the apparent movement of clouds in the extratropics.
It's cleary WRONG. Clouds and lows (at least in my model) move from East
to West, in both hemispheres. One normally doesn't see clouds streaming
across Europe towards the US, nor does one normally see clouds flowing
from East to West across the entire US. At the same time, the pressure
output of the model appears to flow correctly in the extratropics - roughly
West to East. It's a MET 101 league blunder, it's just the model runs slow
enough for it not to be apparent. However, just looking at the curl
of low pressure systems and cold fronts (in the cloud output) also reveals
the problem. Can't believe I'm the first person to notice this...

Whether or not it's just a visualization glitch, or perhaps a more serious
problem ... dunno.

-Eric
2) Message boards : climateprediction.net Science : June Snow on the USA Gulf Coast (Message 11075)
Posted 18 Mar 2005 by Profile old_user55255
Post:
> Mo,
>
&gt; You can see it <a> href="http://members.cox.net/geophi/greenwich_seam.png"&gt;here</a> maybe better.
&gt; Lines point to the discontinuities in the temperature contours along the
&gt; Greenwich meridian. Other areas of globe on the contour view show no such
&gt; discontinuities. At times it's more obvious than others, but it's always
&gt; there. You can see it in the pressure field as well, particularly in the far
&gt; South Atlantic near low pressure areas. Probably just an artifact of the way
&gt; they do their contours in the visualization.
&gt;


Hmmm. yes. One of many strange anomalies I've noted looking at the
SM3 model. And I find it strange they still haven't commented on my
observation of backward moving clouds and low pressure systems
in the extratropics too.

I was trying to be generous by saying it was a display glitch, but it
may well be a more fundamental problem with the model. I know if I was
the one doing the coding I would have fixed such a problem within a week
or less.

Just who is responsible for the code and how many people are working on
the project?

-Eric B

3) Message boards : climateprediction.net Science : Any bets on another TD/Hurricane in South Atlantic? (Message 10281)
Posted 3 Mar 2005 by Profile old_user55255
Post:

Well? Tis the season. I'm hoping for at least another
TD in the South Atlantic. Better yet a weak hurricane

What do you think the odds are?

-Eric
4) Message boards : climateprediction.net Science : \"No Work Available\" (Message 10280)
Posted 3 Mar 2005 by Profile old_user55255
Post:
&gt; Judging by the benchmarks near the start, it's a slow computer.
&gt; And as you can see by scanning through the list, it seems to be in an endless
&gt; loop:

Slow? Judging from those benchmarks glacial is more like it. :)

No offense meant, but it would takes months to complete a model
run on a one-lunged processor like that. Really, only people
with a Ghz class processors should consider running the model, IMO.
It's slow enough as it is.

-Eric
5) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10129)
Posted 1 Mar 2005 by Profile old_user55255
Post:

(...)
&gt; at the cloud display, the movement of extratropical lows (and their curl)
&gt; is the opposite of what it should be, at least based on my satellite POV.
&gt; Things appear to move to the East.

Now I feel like a complete idiot. I meant to say the extratropical clouds
appear to move the WEST. Ack.

-Eric
6) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10128)
Posted 1 Mar 2005 by Profile old_user55255
Post:
Dave, Hi.

Thanks for the response.

(...)

&gt; "Only a few years ago we were told that climate forecasts ``could only be
&gt; taken
&gt; seriously'' if performed with models that could run without surface flux
&gt; adjustment. Now we are told they can only be taken seriously when they
&gt; resolve oceanic eddies. But some aspects of simulated climate change have
&gt; altered remarkably little, notably the overall shape (not the magnitude, which
&gt; depends on the individual models' sensitivities) of the global mean response
&gt; to observed and projected greenhouse gas emissions over the past and coming
&gt; half-centuries. If all the changes in resolution, parameterisations or model
&gt; structure that we attempt fail to alter some aspect of the forecast (the ratio
&gt; of warming over the past 50 years to projected warming over the next 50 years
&gt; under a specific emissions scenario, in this example), then we might hope that
&gt; this aspect of the forecast is being determined by a combination of the
&gt; observations and the basic physical constraints which all properly-formulated
&gt; climate models share."
&gt;

Yes, that's a good point. The fact that many different models tend
to agree in certain areas would make one think, that despite known
deficiencies, the overall approximation is good. This is probably one of
the biggest strengths of the ensemble approach -- it allows one to asses
the skill of a model without having to know or understand every last
detail (which as you pointed out is not possible anyway).

&gt; I think this is quite an important point, and one that a lot of people in the
&gt; climate science world haven't really considered. Given that perturbations at
&gt; arbitrarily small scales can affect arbitrarily large scales in finite time
&gt; [1], it's quite possible (and arguably even defensible) to greet each
&gt; succssive generation of models with "but in order to really simulate the
&gt; climate you need to model process X" (which just happens to be just out of
&gt; reach in terms of scale). This process could go on indefinitely, but is, in my
&gt; view, something of a "god of the gaps" objection. Furthermore, it ignores the
&gt; substantive predictions made by the (successive generations of) models. If
&gt; entire family tree of models predicts the same things (on some scales, in some
&gt; variables) we might have grounds to suspect that there are constraints
&gt; embedded in the models that are making them arrive at these convergent
&gt; predictions. The fact they fail to capture some processes very well needn't
&gt; bear on their ability to simulate others reasonably well. It all depends on
&gt; the nature of the constraints that apply to the particular variable in
&gt; question.
&gt;
&gt; It's an interesting piece of anthropolgy to go to a climate conference and
&gt; listen to the various talks. Very frequently you hear people - interested in
&gt; the Indian Ocean monsoon or ENSO for instance - say that the model fails to
&gt; capture this and fails to capture that and therefore we need to do more work.
&gt; But then those of us involved in the prediction of global means blithely carry
&gt; on and pretend that these objections are largely irrelevant to our work, and
&gt; we fire ahead and issue predictions of global warming to 2100 anyway. It
&gt; sounds counterintuitive, but it's quite possible that both communities are
&gt; justified in what they're doing: current models may be poor at simulating
&gt; equatorial Kelvin waves or flows through the maritime continent, but these
&gt; aren't necessarily relevant to forecasts of global mean temperature, which may
&gt; be much better constrained by things that the model captures quite well
&gt; (energy budget constraints, for example).

Well, I freely admit personal bias regarding tropical convection. It
just happens to be something I like. And I agree 110% that approximating
the overall thermodynamic budget is what really counts for this endeavor.
You're quite right that this project would never get off the ground if
we were to wait for every last detail of the climate puzzle to be 'figured
out'. Given the potential problem of global warming it's essential to
try to get some sort of handle on the problem with the tools and knowledge
currently available.

Just curious if there's yet any consensus on how global warming will
effect tropical convection. I've heard possibly a greater frequency of
tropical storms and hurricanes, but beyond that not much.

The extratropical approximation of the model does look quite convincing,
at least just eyeballing things. However, on my windows computer, the
boinc (v 4.19) screensavers cloud display appears to be reversed (as
I've noted many times already - don't mean to sound shrill :) ). Looking
at the cloud display, the movement of extratropical lows (and their curl)
is the opposite of what it should be, at least based on my satellite POV.
Things appear to move to the East.

It's always easier to criticize than create. I know how much work's
involved in writing a computer program of this magnitude, not to mention
trying to get a handle on all the parameters. I really do think this project
is an excellent idea, and I'm looking forward to seeing the final results
(hopefully within a couple of years?).

PC's have gotten so fast these days, and so many of them are not used
to their potential. I've been trying to recruit friends to the project.

Regards, Eric B

7) Message boards : climateprediction.net Science : Climate change in Australia (Message 10066)
Posted 27 Feb 2005 by Profile old_user55255
Post:
&gt; There was a short article in Sydney's Sunday Telegrah, today from Prof.
&gt; Clyde Wild of Griffith Uni. (Brisbane).
&gt; I Googled the Uni, and then his name, and found an article from the Nine news
&gt; network.
&gt; So it probably won't be there long, but I have a copy.
&gt; Prof Wild is an environmental biologist.
&gt;
&gt; Article <a href="http://news.ninemsn.com.au/article.aspx?id=9558"> here</a>.
&gt; About Prof Wild <a> href="http://www.gu.edu.au/school/asc/academics/cwild.html"&gt; here</a>.
&gt;
&gt; Another article referenced from the 1st about Antartic ice shelf <a> href="http://news.ninemsn.com.au/article.aspx?id=44080"&gt; here</a>.
&gt;
&gt; After this I changed the 2nd search to 'global temperatures' and got <a> href="http://www1.tpgi.com.au/users/mpaine/greenhous.html"&gt; this</a>, which is
&gt; about green house gasses. It contains a lot of links.
&gt;
&gt; Les

More disheartening news. Seems the global warming signal's been
accelerating lately.

This is probably old news to most people here, but <a href="http://www.newscientist.com/article.ns?id=dn6962">here's</a>
a link to a newscientist article about the possible beginning collapse
of the West Antarctic ice sheet. No shortage of gloom and doom news lately.

I really feel the 500 ppm CO2 level is a LOWER bound for what
we will see by the end of this century. Sigh.

-Eric B
8) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10065)
Posted 27 Feb 2005 by Profile old_user55255
Post:
&gt; Eric,
&gt;
&gt; Thanks for the reply.
&gt;
&gt; I'm not so sure about SM failure to treat convection. Cumulus clouds didn't
&gt; display well or at all early in the "Classic" phase but the viz was changed a
&gt; bit to at least partially compensate for that. (Small footprint compared to
&gt; grid cell size.) The weakness of the Slab Ocean is that upwelling and such
&gt; things are not treated -- but that's in the Model run on Cray's and coming for
&gt; the versions we run on our PC's. (Next is Sulfur Cycle and we're in Alpha
&gt; testing for that now. Later in the year, according to plan, the Coupled Model
&gt; [dynamic ocean] is added to the mix. Both require a LOT more calculations
&gt; than the Slab version.)

Oh, I've no doubt the dynamic ocean model is much more computationally
expensive. I look forward to running it. I'm glad to be able to contribute
to this endeavor, if only indirectly.

&gt;
&gt; About circulation. It depends upon which level you see. There was a time I
&gt; earned my daily bread by occasionally riding a big metal bird into Typhoons.
&gt; Spent may hours bouncing around in those things and thought I had a fair
&gt; understanding of them. My first exposures to satellite loops were
&gt; disorienting because the circulation was "backward", i.e., clockwise or
&gt; anti-cyclonic (Northern Hemisphere). Why? Because the satellite loop showed
&gt; Cirrus moving outward as exhaust from the Eye-wall and Cumulus/Cumulonimbus
&gt; cells in the Feeder bands, not the lower cyclonic circulation. Perspective of
&gt; the observer.
&gt;

Ah, well now I'm a bit envious. You've been able to study the beast up
close.

I think the westward movement of clouds shown in the screen-
saver is definitely wrong, even though it's likely a cosmetic glitch.
One normally doesn't see fronts streaming across Europe towards the US.
The model runs slow enough that this is not obvious unless you go
through the work I did to make the movie. I don't think looking at a
statistical average would notice something like this.


&gt; Have you tried the option to selectively shut off display levels?
(...)

Yes, I looked at all the cloud layers. Ditto for all of them.

I was hoping they'd attempt to model tropical waves in the
slab model. I'm still learning.

Why, just today there was quite a flair up over equatorial Africa.
It was only larger than western Europe. Beauty! Just look at those curves! Especially second link.
(hope to get some clickable links below)

<a href="http://www.fractalfreak.com/ClimatePrediction/0226MIR.jpg">Noon</a>
<a href="http://www.fractalfreak.com/ClimatePrediction/0226MIR2.jpg">Six</a>

Regards, Eric B
9) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10064)
Posted 27 Feb 2005 by Profile old_user55255
Post:

(...)

Geophi, Marj,

Thanks for the info. I'll check out CPview.

Yes, I understand this is all about climate and not weather.

Still I hope they get around to fixing the cloud view in
boinc/screensaver - the westward movement of clouds in the
extratropics doesn't look good, though you'd have to be fanatic
to notice it :)

Regards, Eric B
10) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10036)
Posted 26 Feb 2005 by Profile old_user55255
Post:

(...)

Somehow the example link got omitted to some of my strange work:
www.fractalfreak.com

regards, Eric B
11) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10035)
Posted 26 Feb 2005 by Profile old_user55255
Post:
&gt; Eric,
&gt;
&gt; On a more capable BB, I'd send this message to you as a PM (Private Message).
&gt; For obvious reasons. Be that as it may... .
&gt;
&gt; I'm sticking my aged neck out here but, having read your bio and these posts,
&gt; I have no idea who or what you are. Or your real purpose. ... What sort of
&gt; "geek"?
&gt;
&gt; Your posts suggest an advanced knowledge of atmospheric circulatiuon. Your
&gt; language suggests otherwise. (Just an old WX Forecaster's observation.)
&gt;

Hi,

I'm not certain how to parse that last paragraph, but I'll take it
as a compliment.

&gt; Are you perchance associated with a Think Tank? Perhaps one not not favorably
&gt; disposed to this endeavor/endeavour?

No. Absolutely not. Did you read my page regarding the model? I
most definitely DO NOT have a degree in meteorology, though I've
always had a love of meteorology. I did take a couple entry level courses
in college, that's it. But I look at satellite imagery and
movie loops on a daily basis. So it's not like I've got no experience,
and I'd count experience more than a degree in many cases.

&gt;
&gt; Please forgive an old guy's mis-analysis if that not be the case. Otherwise,
&gt; a few words about yourself and what's really going on here seem to be in
&gt; order.
&gt;

I'm a 36 year old autistic, with a lot of experience programming and
using computers. Primarily computer graphics. example,
I came to this project not knowing what to expect, but I was very excited to
be able to finally inspect one of these CGM models up close. On the evening news where I live (US) they've been using CGM models to show the local forcast for several years now - a computer generated display of pressure flows, precip,
clouds, etc. But I know that just because something is modelled on a
computer doesn't mean it's correct. I also know (from experience) that
these computer models are not much more accurate than an experienced
forcaster, and beyond 48 hours aren't worth much. They need to be continually
updated with real world observations to maintain any coherency. I
was disappointed there was no real treatment of convection in the SM.

I've grown increasingly concerned with what I think may be serious
flaws with the model. What's wrong with that? You know, when many
people hear that such and such was modelled on a computer, it tends
to give it an air of legitimacy and authority, but as you know it
really doesn't mean shit. A model is no better than the assumptions
that went into making it.

'What's really going on?' Well, first off, I don't have a hidden agenda
if that's what you're implying. Do you have anything germane to add to my original inquiry? Some of the stuff I've noticed is Met. 101 league
problems, like the movement of extratropical clouds. Assuming my
model is not the only one displaying this behaviour I'm very surprised
it's not already been noticed.

If you care to correct or educate me I'm all ears (or eyes as the
case may be).

-Eric B

&gt; Regards,
&gt; Jim
&gt;
12) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10030)
Posted 26 Feb 2005 by Profile old_user55255
Post:
It's me again. Yes, I'm bogarting my own thread. lol.

Well, I think I found the answer I was looking for, at
least regarding the models treatment of tropical convection.
This excerpted from HCTN-51 (off the hadley site) where
they are discussing the performance of tropical convection
in the coupled models

"
Convectively coupled equatorial waves are a key part of the tropical
climate system. A faithful representation of these wave modes is
needed for predictions on all time-scales. However, at present there
is little understanding of how well they are treated in state-of-the-
art models and knowledge of these waves is very limited
"

There you have it. I would like to add the above should
be amended to say that equatorial waves are ONE of the keys
to understanding the GLOBAL climate system.

Unless some sort of understaning of tropical convection can
be achieved (certainly greater than we have now) you aint
got a working global climate model, in my very honest opinion.

I've developed quite a fetish for tropical convection from
looking at satellite imagery. Awesome stuff. Each wave, each
region, has a certain uniqueness that I find impossible to
quantify.

Regarding the western movement of clouds in the extratropics -
this needs to be fixed, assuming it's not a parameter issue. It
may be something as simple as a display glitch (meaning the
model is correct internally, but the display routine is flawed)
or it may be flawed throughout (in which case it doubly must be
fixed). I hope thay aren't hesitant to admit this (assuming
the later case) given the large number of model runs that may
be of questionable quality because of this.

nuff said

-Eric B

13) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 10001)
Posted 25 Feb 2005 by Profile old_user55255
Post:
&gt; Eric, I think a lot of your questions can be answered in the Hadley Centre <a> href="http://www.metoffice.com/research/hadleycentre/pubs/HCTN/index.html"&gt;technical
&gt; notes</a> and <a> href="http://www.metoffice.com/research/hadleycentre/pubs/refereed.html"&gt;refereed
&gt; publications</a>. I have not read many of them myself yet, but several from
&gt; their titles look like they are what you want.
&gt;
&gt; I think you miss quite a few of the things the models get wrong, tropical
&gt; clouds are difficult, but so is the motion of pack ice (in the HadCM3 model)
&gt; and some of the more localised climate features (e.g. NAO, I can't remember if
&gt; the HadSM3/HadCM3 models get this right)
&gt;

Hi,

Thanks for the links, but can you be more specific? There's dozens of
technical briefs on the page. Did you look at my page and the animations
from my model output? (especially the first movie loop showing the
flawed extratropical cloud circulation about the south pole?) What points
did I miss?

I understand tropical convection is very difficult too model, and the
need to simplify the problem to its essence, if possible. It's just
from what I can see it's not being done -- at least from looking at my
model output I see no evidence of it. The cloud model (assuming it's
not just a gltich in the routine to display the clouds from the internal
model representation) is out of whack with the pressure and temp models.
This alone would mess up critical feedback processes.

I was hoping for a quick response and rebutal of my page. I also
sent a note to the climateprediction people, but have yet to hear
back from them. Do you think I should attempt to bother the hadley
people directly?

Thanks, Eric B
14) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9944)
Posted 25 Feb 2005 by Profile old_user55255
Post:
(...)

I just corrected some stupid mistakes in my hastily
thrown together page, where I said things were moving
East when I meant West and the other way around.

Gist of the <a> href="http://www.fractalfreak.com/ClimatePrediction/index.html"&gt;page</a> is the same though.

-Eric

15) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9943)
Posted 25 Feb 2005 by Profile old_user55255
Post:
&gt; (...)
&gt; &gt;
&gt; &gt; BTW what is the typical latitude which divides the Polar Cell from the
&gt; Ferrell
&gt; &gt; Cell in the Southern hemisphere?
&gt; &gt;
&gt;
&gt; Crandles, I'm not certain. Most of what I know is based on observations
&gt; of satellite imagery. I could go paw through my old Met textbooks and
&gt; find out. It's not a hard dividing line, obviously.
&gt;
&gt; Point to be made is the prevailing winds off the coast of antarctica
&gt; are westerly (and, come June they'll be screaming). Looking at my first
&gt; movie, concentrate (radially) on the outer half of the globe, towards the
&gt; few continents vis. in the SH. The flow is clearly backwards, at least in
&gt; the cloud output.
&gt;

Ug, yes, I meant to say the prevailing winds around antarctica,
and into the mid latitudes usually move eastward. The model doesn't
seem to do a very good job with commonly found blocking patterns
nor extreme events either. The more I look at the pressure output the
more 'sanitized' it appears.

-Eric
16) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9925)
Posted 24 Feb 2005 by Profile old_user55255
Post:
&gt; &gt;I worry they may have crippled the model so it will run
&gt; &gt;in a reasonable amount of time so people will not loose
&gt; &gt;interest.
&gt;
&gt; No, don't worry about that.
&gt; The sulphur cycle is under Alpha test and it lasts about 2000 hours on my
&gt; machine (~750 hours for the regular model), so I don't think the model is
&gt; crippled for time reason.
&gt; If devs team needed to do models during 5000 hours or more, I think they would
&gt; find fanatic users to crunch such models.
&gt; Nonetheless, I understand your point about coarse resolution of the model.
&gt;

Oh yes, I'm certain they'd be able to find poeple to run
the expensive models; I'd be one of them. So I hope they
don't hesitate to 'open the valves' on the computational
complexity.

I'm glad you agree on the coarseness of the model. Even they
admit the timestep of 1/2 hour is pushing the limits of stability
on the iterated time-step approach.

When I was younger and more ambitious I used to think 'solving'
(simulating) global weather was possible. More and more I wonder
if the problem is completely intractable on the scale being attempted
here. The atmosphere is very much alive. The energy flows and
comlexities beggar the imagination, especially any attempts at
conceptually glossing the problem over. After watching satellite
imagery for years I've come to this conclusion. Never make the mistake
of confusing any model for reality.

That said I still think this is worthwhile project.

-Eric
17) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9913)
Posted 24 Feb 2005 by Profile old_user55255
Post:
(...)
&gt;
&gt; BTW what is the typical latitude which divides the Polar Cell from the Ferrell
&gt; Cell in the Southern hemisphere?
&gt;

Crandles, I'm not certain. Most of what I know is based on observations
of satellite imagery. I could go paw through my old Met textbooks and
find out. It's not a hard dividing line, obviously.

Point to be made is the prevailing winds off the coast of antarctica
are westerly (and, come June they'll be screaming). Looking at my first
movie, concentrate (radially) on the outer half of the globe, towards the
few continents vis. in the SH. The flow is clearly backwards, at least in
the cloud output.

-Eric
18) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9911)
Posted 24 Feb 2005 by Profile old_user55255
Post:
&gt; Hi,
&gt;
&gt; I read your article, and found it interesting.
&gt; As I'm not a climatologist nor a computer geek, so I can't answer rightly but
&gt; I'm going to give my point of view.
&gt; The atmosphere is divided into 19 layers and just 4 of them are shown on the
&gt; screen-saver.
&gt; I don't think seeing 4 layers of cloud is sufficient enought to conclude that
&gt; the model is unrealistic.
&gt; This is why you seem to think that temp and pressure are more or less OK but
&gt; cloud layers are terrible: you don't see the whole picture.

True, but I don't think the cloud movement can be explained by
hidden layers. Supposedly the model shows three layers of clouds -
I would hope these would be distributed throughout the modelled layers.
And deep tropical convection should show up on ALL cloud layers.

(...)

&gt; Second thing: the hadsm3 model is a simplified model, with a slab ocean.
&gt; Perhaps the atmosphere is also simplified: Perhaps the globe isn't turning and
&gt; so no Coriolis Acceleration is created: so you don't see all twirling and
&gt; convection phenomenas.

Yes, yes I'm aware of the limits on the slab model. And no, the
coriolis force is there, it's just plain wrong, at least from looking
at the cloud output.

&gt; Well I don't know: Perhaps someone more qualified than me will answer your
&gt; questions.
&gt; Later in this year a more realistic model (coupled model) will be released and
&gt; perhaps will take into account more physical parameters.
&gt;

Yes, a more realistic model is needed. The slab model is cute, but it's
almost an insult to a problem of this magnitude. Years ago I was
interested in writing my own global weather simulator, but I gave
up when I realized the computational complexity - I didn't want to
wait days for each frame to complete. The coupled ocean model being
worked on is a good thing. And I still think the sampling scheme is
too course. I worry they may have crippled the model so it will run
in a reasonable amount of time so people will not loose
interest. I'd be more interested in a much more comprehensive model,
even if it takes a year or two to complete a model run. I'm certain
they'd loose some poeple from the project is thie were the case, but
no doubt many would remain, and the model output would be more realistic.

&gt; Last thing: You should use CPview or the Advanced vizualisation package that's
&gt; going to be released for BOINC to do your work because taking screenshots of
&gt; the screensaver is not a very accurate tool.

Well, the cpdn visualization package (cpdn_viz2, which I downloaded) would
not run on my (windoze) computer. I was told they were working on
getting it running. This would certainly be perferable to using
ctrl-c/ctrl-v :)

-Eric B
19) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9909)
Posted 24 Feb 2005 by Profile old_user55255
Post:
hi

&gt; Interesting stuff. Especially the clouds going westward in the southern
&gt; hemisphere. I hadn't looked at any time lapses of CPDN output like that
&gt; before.

Yes. In fact, from what I can see, ALL cloud patterns on my computer
move eastwards, including in the northern hemishpere. The clouds
seems to be almost an afterthought compared to the temp and pressure
outputs (the pressure output DOES move westerly in the extratropics,
as it should). Looking at the statisitcal average of the cloud
cover would never have caught the problem, IMO. From what I can
see the cloud model is waaay too facile, and amounts to little more
than eye candy.

&gt;
&gt; I'll let the modelers explain what you are seeing.
&gt;
&gt; But as for Linux users not being able to view .wmv files, not true. Most
&gt; modern Linux distributions have a media player that will play Windows media
&gt; files, and if not, VLC or MPlayer can be downloaded and installed to view
&gt; them.
&gt;

Good to know, I'm glad more than just windows users have
the potential to view the movies - I was worried about that.
If it wasn't for video games I would've have ditched windows
long ago. Though I must admit the latest versions on windows
(XP pro/NT) are quite robust and stable compared to earlier versions.

&gt; I'm not sure how you captured images, but using Alt-PrintScrn will capture
&gt; just the active window to clipboard so the capture is the same size each time.
&gt; But <a> href="http://www.brothersoft.com/Multimedia_Graphics_Screen_Capture_WinGrab_6192.html"&gt;WinGrab</a>
&gt; should be able to capture individual window contents at timed intervals for
&gt; later generation into an animation. This may be helpful if you want to do
&gt; more.
&gt;

Thanks for the link. I see you've got to embed the links in html
style tags to get them clickable. I wondered why my link
didn't come up as clickable... (maybe I can edit my original
post?)

Regards, Eric B
20) Message boards : climateprediction.net Science : Problems and reservations regarding HadSM3 (Message 9876)
Posted 24 Feb 2005 by Profile old_user55255
Post:
I recently joined the climate prediction experiment.

After observing the model output on my computer (still phase 1), I now feel there may severe problems with how the model approximates cloud cover, and especially tropical convection. To the point where I must question the integrity of the model itself.

I understand the probabilistic nature of the experiment, but given some of potential problems I've noted I've got to wonder how accurate the overall endeavour can be considered. Just as the slab ocean model puts serious limitations on the model (hence the need more the more accurate coupled model in the next step), I feel the models treatment of clouds and tropical convection may also put similiar restrictions
on it - despite its statistical nature. I'm not aware of how the model is dealing with these things internally, so I may well be wrong.

I've noticed some very basic problems - clouds and fronts in the extratropics retrogading (easterly) with respect to pressure variations. A seeming lack of any apparent convection in the tropics, or for that matter accurate clouds of any sort. Strange pressure anomalies. Weird snow and ice extents. Again, some of this may be due to the parameters on my particular model... I've put together a page with animations spanning several model days off my computer and omparisons to actual satellite images I've collected over the years:

http://www.fractalfreak.com/ClimatePrediction/index.html

Yeah, it's a rather large page. Kinda blew up on me :(
If you want to skim it, check out the top text and links to the first two .wmv movies. Also check the botton of the page to see some of the strange pressure anomalies I've observed.

I figure modellers always need feedback, which can be hard to come by ... :)

Anyway, let me know if you think there's anything to my concerns.

-Eric B


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