2011-10-18 08:22:28CharlieA needs guiding
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

He was asked to post his questions in the Lindzen thread, but so far he has ignored that request.

2011-10-18 09:19:21
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

I don't really mind answering his questions in that thread.  Problem is he's not listening to me, or not understanding what I'm saying.  He's harped on baselines in almost every 'Lessons' post though.  I hate when people harp on baselines.

He's also a Lucia fanboy, which explains a lot.

2011-10-18 09:43:18
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Dana,

OK, sorry about that-- this baseline stuff it is all quite irrelevant though IMO, but "skeptics" love to make a meal of it every opportunity they get.

Have a got this right the digital AR4 data you got online was baselined for 1980-1999 right (that rmeinds me I dd try and locate digital data for TAR but had no luck, sorry for not letting you know!).  You then changed those model output anomalies to correspond to the 1951-1980 baseline, right?  Linden's data is baselined wrt the 1951-1980 baseline, same as GISTEMP and the models, right?  That is why he is so low-- Lindzen claimed 0.01 C /decade warming since 1880, so circa 1989, his estimate would be about -0.2 C wrt to the 1951-1980 baseline, instead of -0.3 C in 1880.

The big difference of course is that his rate of warming is more than an order of magnitude too low.

Did you ever contact him to let him know about your post?  If you did and he did not responf or raise any objections, then that should be noted.

2011-10-18 10:54:46
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

I agree - I hate when people start complaining about baselines because when talking about the amount of warming, baselines mean diddly squat.  It's just something for the fake skeptics to nitpick about.

In general I just adjusted the baselines such that the projections were the same as the GISTEMP 5-year running average when the model run starts, because we want to know how the warming in the two compares from then on out.  So for example, the Hansen projection matches the GISTEMP 5-year average in 1984, as I recall (even though the study was published in 1988, the model run began in '84).

For Lindzen I matched his reconstruction with the average in 1880, then ran it forward at 0.1°C/century with random noise added in.  The difference is that a big part of his comments in the 1989 MIT Tech Talk involved arguing that the surface temperature record was wrong, and there was only 0.1°C warming from 1880 to 1989.  All the other projections assumed the temperature record was correct.

I don't remember if I emailed Lindzen - I think I did, way back when I published the post, but can't recall.

2011-10-18 13:14:20
Sphaerica

Bob@Lacatena...
76.28.5.93

I think, taking a skeptical point of view, that the graph "looks" bad.  Because it doesn't match actual temperatures at any point the immediate assumption is that you just wanted to make Lindzen look silly, and as inseparable as the two issues are, Lindzen endures the confluence of two mistakes, one of which is a sensitivity that is too low to account for temperatures since 1989, but the other is a sensitivity that is too low to even reach temperatures in 1989.

In fairness, you should either separate the two and raise Lindzen's baseline (with a sarcastic comment that points out the compromise that you are making for him), or alternately provide a graph that goes back to 1880 where his own baseline begins.

Just my opinion.  I and anyone who bothers to read will understand what you're doing (although even that is not really explicitly clear from the text), but it's a really easy mistake for people to make, and I'll bet Anthony could have a field day selling the false view of things to the uncritical masses.

2011-10-18 14:06:20
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Hi Dana,

 

Thanks.  But I'm still confused.  If his baseline is 1880, then his "forecast" would start at zero in 1880.  It obviously does not, but it does seem to match with the 1951-1980 baseline though.  What am I missing?

2011-10-18 15:15:36
dana1981
Dana Nuccitelli
dana1981@yahoo...
69.230.101.55

It matches GISTEMP in 1880, which isn't zero, it's somewhere around -0.45.

2011-10-18 15:41:40
Albatross
Julian Brimelow
stomatalaperture@gmail...
199.126.232.206

Hi Dana,

Thanks. I'm still confused re Lindzen, but I'll let it go :)

I guess my question is, does Charlie have a point re the offsets?

2011-10-20 02:49:51
Kevin C

cowtan@ysbl.york.ac...
144.32.72.165

I thought he did, and so made the case on the Lindzen thread. Bob pointed out some of the issues. My understanding based on his comments is that Lindzen's view of the past was so counterfactual that any starting point is pretty much a judgement call.

I'm interested that Charlie didn't turn up on the Lindzen thread though. I suspect he is evolving a strategy here:

1. Post early, only on the first page.

2. Pick topics which migh expect a high number of visits.

3. Only pick topics where he can make a plausible case. He's smart, and he does his research.

4. He may be focussing specifically on Dana or on the Past Predictions series. That may in part be becaue he's had some success there.

Not sure what to do about it. If I had more time I'd offer to try and wear a Charlie hat to critique everything Dana does before release for a while, but I don't have remotely enough time to cover anything Charlie might decide to pick on.