November 7, 2009
Category: climate fuels
So says Sci-Am. The article is high on pic and low on facts. Only a small percentage of the CO2 is captured - 1.5% - but that is OK, it is only a demo plant. The key question, of course, is how much extra coal is burnt to achieve this? This vital fact is not clearly provided. The 1.5% is clear And now roughly 1.5 percent of the CO2 billowing from its stack is being captured... but the other half is vague: But the primary benefits of the chilled-ammonia process for capturing CO2 are lower electricity and steam consumption, compared with other potential technologies for carbon capture, such as using amines, another ammonia compound, which can consume as much as 30 percent of the plant's power just to run, says Shawn Black, product manager for Alstom. The goal here is to get that number down to under 15 percent. So is that 15% of 1.5%, which seems to good to be true, or 15% of the total, which seems too bad to be true?
Wiki says Capturing and compressing CO2 requires much energy and would increase the fuel needs of a coal-fired plant with CCS by 25%-40%.[2] These and other system costs are estimated to increase the cost of energy from a new power plant with CCS by 21-91%.[2] That is more in line with what I was expecting. [2] turns out to be a 2005 IPCC report. Their table SPM 3 (yes, its true, I didn't get very far through) says that coal, sans CCS, is 0.04-0.05 $/kWh, and 0.06-0.10 with CCS and geological storage. The Sci Am article is consistent with that, saying Cleaner coal will be more expensive, too, adding at least 4 cents per kilowatt-hour to the power Mountaineer produces at roughly 5 cents per kWh. So I think they do mean 15% or 1.5%, but are probably being optimistic.
Clearly, until carbon acquires a sensible price (hopefully via a carbon tax) these plants will not be commercially viable.
In other news, Mars looks good.
Posted by William M. Connolley at 12:51 PM • 4 Comments • 0 TrackBacks
November 6, 2009
Category: sea ice
Nothing new, but M pointed me at Greenman on sea ice which has a quote from Wadhams (starts around 5:00, quote around 5:20 I think) that is the "the arctic will be ice free in summer in 20 years" or words to that effect (which got noted in my Arctic to be 'ice-free in summer'?.
I still don't believe it, not that that matters. Watch the video anyway for a glimpse of Wadham's / SPRI's rather haphazrd filing system.
Posted by William M. Connolley at 4:54 PM • 9 Comments • 0 TrackBacks
November 5, 2009
Category: misc
To the city fireworks. Park in Mount Pleasant House and walk with the children to the river, when James and Emma and James and Amy are having a party. Arrive in time for the mulled wine to just run out; watch the fireworks (ooh! ahh! how long do these go on for?); tour of the boats (hello Lyra!); hello people; home.
Posted by William M. Connolley at 5:08 PM • 0 Comments • 0 TrackBacks
November 4, 2009
Category: climate science
Tiljander and od^4 refer.
Over the past few days, it has become clear to me that the entire issue of "flipping" or "upside-down-ness" of the Tiljander proxy is a red-herring.
Here's why:
Imagine a climate proxy, accurate over the last 2kyr, that shows (for example, let us suppose) a warm period around 1000 AD and which, undisturbed, would show the recent warming. Further suppose for definiteness that this proxy is of such a nature that increases in the proxy value represent increases in temperature. Imagine this proxy is contaminated with non-climatic signal over the last 200 years, enough that the climatic signal is overwhelmed. Suppose that this contamination is of such a nature that it leads to a strong decrease in the values of the proxy over the last 200 years. Such a proxy (call it A), fed into the Mea algorithm, will be flipped over (due to its negative correlation with recent instrumental temperature) and will contribute a net cold influence around 1000 AD. How much it contributes will depend on how well it correlates to recent times.
Now imagine a similar proxy, except the nature of the non-climatic contamination is such as to add a strong increase over the last 200 years. We'll call it B. This time, the proxy won't be flipped over, because its correlation to recent times will be positive. But the variance into the past will be strongly de-weighted (because we've just added an artificially large postiive trend). So it will imply not much change around AD 1000. But now we see this, we can see that the same problem applies to series A: unless, by bizarre co-incidence, the negative non-climate signal just happens to match the true positive instrumental signal, the variance in the past will be wrong. And since we've had to assume that the non-climate signal overwhelms the climate one, its likely that the recent variance will be too large, so the past will be de-weighted.
So in either case we can see that the real problem is the addition of the non-climate signal. The flipping is of little relevance.
Note to the Fanboyz: the comment policy will be vigourously applied. If you don't like it, DenialDepot is your friend. Note to everyone else: don't bother reply to comments you know I'm going to delete ;-)]
Posted by William M. Connolley at 3:49 PM • 36 Comments • 0 TrackBacks
November 3, 2009
Category: Piers
Its fish in a barrel time, but Corbyn seems to have had his International Conference. It doesn't look very exciting. As RB says: Did the meeting live up to its billing of "refuting, totally, the CO2 theory of warming"? Hardly. Because doing that seriously doesn't mean refuting it to my satisfaction, or yours, or that of the audience scattered about the Imperial College lecture theatre on Wednesday; it means convincing the greater community of climate scientists, and that brings us back to... publishing. What some in the sceptical camp do not appear to appreciate is that published, peer-reviewed science is not only the sole way of establishing and improving theories; it's also, now, the only route to the policymakers they want to influence. Modern-day ministers and their scientifically-qualified advisers are absolutely not going to listen to half-developed, unpublished theories or complaints about fraud and conspiracies.
Posted by William M. Connolley at 4:42 PM • 11 Comments • 0 TrackBacks
November 2, 2009
Category: climate communication
Yes indeed. Sorry. Weeelll. No I'm not, really.
Anyway, so I was idly browsing my "shared by" in google reader and came across My Rebuttal to Romm which is by Keith Kloor who I know nothing about other than that I read Joe Romm ranting at him at some point. Kloor defends himself - read it if you're interested - but more amusing was a comment left there which said: I'm not sure the whole huge post needs to be answered point-by-point. Morano feels comfortable just pointing to Romm posts and letting them speak for themselves though it didn't say where this Morano linking occurred. But http://www.climatedepot.com/ (an amusing parody of denialdepot) seems to do it (in the interests of sanity I haven't linked it): look at the current front page and there is a link to http://climateprogress.org/2009/11/01/keith-kloor-trash-journalist/, under what is a fairly neutral link-text. You do have to wonder, as the commentator suggests: what does it tell you about Romm that Morano is happy to link to him?
Why does Romm hate Kloor so much? I don't know. Probably he is jealous of Kloor's column in Nurture :-). You'll immeadiately notice the rabid scepticism in that piece, of course.
[While I'm here: don't miss Where's the Science at ScienceBlogs? - thanks mt :-)].
[Update: Malformed html somewhat mangled this post; fixed at 2009/11/03:18:50 UK time -W]
Posted by William M. Connolley at 5:06 PM • 70 Comments • 0 TrackBacks
Category: climate communication
[This one for James, of course.]
I do so love the word "seminal", it brings back my public school days. Anyway, Nurture writes: Oxford climatologist Myles Allen and collaborators, who, in April this year, published two seminal papers in Nature..., which were Warming caused by cumulative carbon emissions towards the trillionth tonne and Greenhouse-gas emission targets for limiting global warming to 2 °C. I'd say both are mere headline-grabbers of little scientific novelty and doomed to be rapidly forgotten.
And do you know, as I was driving in this morning, I was thinking to myself " you know I really ought to try to be nicer and more positive about things".
Posted by William M. Connolley at 4:47 PM • 13 Comments • 0 TrackBacks
November 1, 2009
Category: misc
Halloween. I went as the Spirit of the Night though Patrick thought I was Ash Man. It came off, fortunately.
Sunday was wet, so over the new bridge to the Museum of Technology which is a rather odd place, housed in the former sewage pumping works and city rubbish burner, now housing a miscellaneous collection of engines pumps and random electical items from Cambrdige's industrial heritage; and run by a collection of enthusiasts. Its great failing (compared, say, with the FitzWilliam) is that it doesn't have a decent cafe, or indeed a cafe at all really (though they will sell you a coffee at the ticket kiosk)).
They were hosting a Teslathon which was an occaision for an even odder bunch of enthusiasts to gather and mostly show each other their endeavours, though incidentally the public too. I later find some stuff on wiki about this, and find I'd guessed some of it right - the spark-gaps are to generate AC but the hair-dryer isn't there to cool it down, it affects the frequency. On guy had managed the trick of getting them to play music, and had a version that would rotate round as the sparks exited. The bigger machines were very very noisy - the spark gap I think. Sadly they didn't have much in the way of explanation available on site.
Daniel thought that the rock crushing machine was the best. 
Incidentally: from the Rubaiyat:
Ah, fill the Cup:---what boots it to repeat
How Time is slipping underneath our Feet:
Unborn TO-MORROW, and dead YESTERDAY,
Why fret about them if TO-DAY be sweet!
- why does this make sense? Why not "unborn yesterday and dead tomorrow"? Someone explain it to me. [Update: Sidd has done so; my thanks. Unborn/Dead refer to the days, not to the people. La! -W]
[Update: http://picasaweb.google.com/thouky/CambridgeTeslathon2009?authkey=Gv1sRgCMHLkJO254G_LQ&feat=directlink# too -W]
Posted by William M. Connolley at 10:29 AM • 1 Comments • 0 TrackBacks
October 29, 2009
Category: climate science
It seems like everyone wants to talk about Tiljander. I don't, particularly, but you gotta give the customers what they want, so here is a thread to discuss it if you like. The comment policy still applies, but I'll be laxer. Comments incorrectly paraphrasing others will be harshly dealt with. Vague rantings unsupported by clear evidence or links, ditto. Repeating what everyone else has already said, ditto (this isn't a vote).
Some useful links you may want:
- Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia (Mea; includes supplementary info)
- McI's comment on Mea
- Mea reply to McI
- [Update: Supplemental Information for PNAS Article at Mann's website, plus updates
Hopefully, people have read the Mea supplemental info where they say Potential data quality problems. In addition to checking whether or not potential problems specific to tree-ring data have any significant impact on our reconstructions in earlier centuries (see Fig. S7), we also examined whether or not potential problems noted for several records (see Dataset S1 for details) might compromise the reconstructions. These records include the four Tijander et al. (12) series used (see Fig. S9) for which the original authors note that human effects over the past few centuries unrelated to climate might impact records (the original paper states ''Natural variability in the sediment record was disrupted by increased human impact in the catchment area at A.D. 1720.'' and later, ''In the case of Lake Korttajarvi it is a demanding task to calibrate the physical varve data we have collected against meteorological data, because human impacts have distorted the natural signal to varying extents''). These issues are particularly significant because there are few proxy records, particularly in the temperature-screened dataset (see Fig. S9), available back through the 9th century. The Tijander et al. series constitute 4 of the 15 available Northern Hemisphere records before that point.
In addition there are three other records in our database with potential data quality problems, as noted in the database notes: Benson et al. (13) (Mono Lake): ''Data after 1940 no good-- water exported to CA;'' Isdale (14) (fluorescence): ''anthropogenic influence after 1870;'' and McCulloch (15) (Ba/Ca): ''anthropogenic influence after 1870''. We therefore performed additional analyses as in Fig. S7, but instead compaired the reconstructions both with and without the above seven potentially problematic series, as shown in Fig. S8.
So you can look at S8 - I've inlined it - to discover that the Tiljander series don't affect the overall result much.
[Didn't like this post? You want DenialDepot]
[Update: one thing that has puzzled some people is how little effect the Tiljander proxies have on the overall reconstruciton: see S8, which I inlined. But look at S9, and you'll see that the Tiljander proxies are remarkably flat before 1800. This would be consistent, for example, with recent non-climatic artifacts producing more variation than is naturally present. But it also means that the effect of these proxies on the total reconstruction pre-1800 is likely to be extremely slight (which explains fig S8). This is because the scale-this-proxy-to-termperature thingy is done on the overlap with the instrumental period -W]
Posted by William M. Connolley at 6:10 PM • 111 Comments • 0 TrackBacks
My family and me.
