tag:blogger.com,1999:blog-9959776.post4477517303539006851..comments2024-02-15T04:42:41.606+00:00Comments on James' Empty Blog: TsukubaJames Annanhttp://www.blogger.com/profile/04318741813895533700noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-9959776.post-45865706609951540312011-02-20T12:02:12.570+00:002011-02-20T12:02:12.570+00:00Well found - with you around, maybe I don't ne...Well found - with you around, maybe I don't need to keep note :-)<br /><br />OK, I have updated the page...James Annanhttps://www.blogger.com/profile/04318741813895533700noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-83868120721940880422011-02-10T12:45:27.674+00:002011-02-10T12:45:27.674+00:00Perhaps
http://julesandjames.blogspot.com/2007/12...Perhaps <br />http://julesandjames.blogspot.com/2007/12/another-bet-on-not-so-much-climate.html<br /><br />should be added to <br /><br />http://julesandjames.blogspot.com/2005/06/betting-summary.htmlcrandleshttps://www.blogger.com/profile/15181530527401007161noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-53400844030625784622011-02-10T07:45:29.764+00:002011-02-10T07:45:29.764+00:00Tell you what, I bet you can't work out how to...Tell you what, I bet you can't work out how to tranche that bet effectively, but if you do, I'll take a percentage off each trade rather than a position either way :-)<br /><br />At a (very quick) glance, that linked paper is purely observational, that is the comments about models seem entirely hypothetical (well, other than that they are generally evaluated firstly on means rather than on variability). So it's not clear that the models actually do have any related failings, though the authors may have some reasons to suspect it. Not that this is meant as criticism, there is only so much work one can be expected to do per paper, especially these days when the count matters more than the content.James Annanhttps://www.blogger.com/profile/04318741813895533700noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-18489011167227418562011-02-10T07:25:15.348+00:002011-02-10T07:25:15.348+00:00Aha, a bet on a bet! May I package that for sale ...Aha, a bet on a bet! May I package that for sale in several tranches? :)<br /><br />Chris, bear in mind that Romm is now hiring staff, so he probably needs the money more, and anyway all J+J are likely to do with any winnings is blow it on more Apple paraphernalia. :) <br /><br />Speaking of sea ice and model skill, note the new paper discussed <a href="http://www.giss.nasa.gov/research/briefs/delgenio_06/" rel="nofollow">here</a>. I haven't read it yet (have asked for a copy), but Mahlstein and Knutti's near-contemporaneous effort springs immediately to mind. I think you said it was on your reading list when I mentioned it a few months ago, James, but now I'm wondering if there will be any models left standing after the filters proposed by these two papers. I would be extremely interested in your take on both papers.Steve Bloomnoreply@blogger.comtag:blogger.com,1999:blog-9959776.post-54874181276200781492011-02-10T02:55:46.141+00:002011-02-10T02:55:46.141+00:00TBH I can't remember exactly what I bet with R...TBH I can't remember exactly what I bet with Romm, but I bet I was right whatever it was :-)<br /><br />I suppose rather than waiting for a large change it might be possible to hindcast situations where there has been a directly imposed change in land cover (urbanisation or cropping) and see whether the models got the change right. Actually now I htink about it, surely this must have been done on lots of occasions, even if the analysis was not pursuing this precise question ("skill" is a rather technical concept).James Annanhttps://www.blogger.com/profile/04318741813895533700noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-59681255984383423542011-02-09T14:50:17.571+00:002011-02-09T14:50:17.571+00:00I hope you are right, and win you bet against J Ro...I hope you are right, and win you bet against J Romm. Presumably that would make Maslowski's projection of 2016 +/-3 years wrong.<br /><br />Are you still willing to take more bets on same terms as Romm? <br /><br />5 years data after first down to 10% of pre 2000 coverage to have any hope of verifying predictions would appear to mean it could be as little as 10 available years if Maslowski is right. So there could well be sufficient spare time to collect a couple of years of cryostat2 data before getting around to talking about whether it is worth doing, decide how to force the models, prepare grant proposals, prepare and run models, collate results, attempt to get published....<br /><br />Obviously there is plenty of scope for me to be way out on estimating such timings.crandleshttps://www.blogger.com/profile/15181530527401007161noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-88792234621228243102011-02-09T12:33:24.314+00:002011-02-09T12:33:24.314+00:00Yes, you are right that predicting changes over a ...Yes, you are right that predicting changes over a few years doesn't make much sense, as the natural variability will swamp any forced change. I'll have to think about the sea ice...you mean predicting what will happen in (say) 20 or 40 years when there is no sea ice? That still doesn't help us evaluate the models now...<br /><br />Some participants talked about hindcasting recent forced changes...but they haven't been large on the local scale, especially not precip...James Annanhttps://www.blogger.com/profile/04318741813895533700noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-36855553127758428082011-02-08T23:56:15.539+00:002011-02-08T23:56:15.539+00:00It seems to me that the response to forcing of a f...It seems to me that the response to forcing of a few years CO2 accumulation is likely to be small unless something creates some non-linear behaviour.<br /><br />So it would appear to me to be difficult to demonstrate skill (or lack thereof) over small time and space scales to a general CO2 accumulation forcing.<br /><br />Would it be easier to demonstrate skill where the forcing is something more like the arctic becoming seasonally sea ice (nearly?) free?<br /><br />If so, I would have thought that there should be lots of modeling of the effects of this.<br /><br />Perhaps there is still lots of time for that to be done as forecast rather than as hindcast?crandleshttps://www.blogger.com/profile/15181530527401007161noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-50553803929053711402011-02-08T22:34:45.370+00:002011-02-08T22:34:45.370+00:00The "skill" most needed is in projecting...The "skill" most needed is in projecting regional precipitation [with much more than just annual averages required].David B. Bensonhttps://www.blogger.com/profile/02917182411282836875noreply@blogger.comtag:blogger.com,1999:blog-9959776.post-61487243900737881282011-02-08T13:56:55.848+00:002011-02-08T13:56:55.848+00:00And again,
http://www.youtube.com/watch?v=UM6yfh...And again,<br /><br /><br />http://www.youtube.com/watch?v=UM6yfhFULYIAnonymousnoreply@blogger.com