Thursday, April 23, 2015

Trek recall of 1,000,000 bicycles

Better late than never perhaps, Bikebiz reports that Trek has issued a 1 million bike recall notice relating to QRs loosening and causing crashes. There's still plenty of misdirection and obfuscation, of course. Trek's notice refers to QRs that can open beyond 180 degrees such that the lever gets caught in the disk or wheel. But all their original arguments were that if correctly installed, the QR cannot come loose in the first place. Sadly this is not true, as has been amply shown in practice and supported by the simple theory that I presented a decade ago. That is, under the strong transverse forces that are generated in normal use of disk brakes, the phenomenon of vibration loosening may result in unscrewing of the nut and loosening of the QR. This is elementary engineering that has been known for decades, though poor design and maintenance means that it still crops up occasionally, eg as the cause of this rail crash a few years back.

The last version of my web page discussing this seems to be on the wayback machine here. Perhaps I should get round to hosting it somewhere again. But it's old news, and all I got from it was a load of grief from ignorant numpties who didn't care if others were seriously injured by this shoddy design. Shame it took another case of paralysis before Trek started to take it seriously. Hope there aren't too many more, but at this point it's hard for me to do more than shrug and say "told you so". The QR system is simply inadequate for bicycles equipped with disk brakes. It was never designed to take the forces involved, which are massively greater (and in a different direction) to those generated with conventional rim brakes. Fiddling around with it to try to patch up the problems is no alternative to just implementing a sensible robust design (of which there are several available).

Saturday, April 18, 2015

[jules' pics] Vienna Market

 Subliminal wise advice for those who have been exercising their brains too hard at the EGU all this week.

Posted By Blogger to jules' pics at 4/18/2015 05:22:00 PM

Tuesday, April 14, 2015

Overconfident and undertrained

Saw a runner wearing a t-shirt with that written on her back half-way round the Vienna marathon on Sunday...about 10km further on I was thinking I should have asked her where she bought it so I could get one too!

As I mentioned before, the coincidence of Vienna marathon and EGU General Assembly was too good to miss so we signed up some time ago. But especially with the surprise run at Chesterfield, I didn't have massive motivation for serious training and over the last few months we've also been a bit busy with trips both professional and personal. So although I started out with good intentions, my mileage was well down on what I managed last time, though doing some running with the local club did increase the intensity. Jules has been an even more intermittent runner through injuries. But we thought it would be fun to take part in this big event anyway, having watched it a couple of years ago. We came out to Vienna on Friday, and are staying in a lovely apartment (found via Airbnb) on Nestroyplatz, handy enough for the town centre and ideally placed for the EGU and marathon (which started at the same place). Picking up our race numbers the day before the race was a bit of a pain to be honest - why can't they just post them? - but having seen plenty of Vienna over the years we were not desperate to traipse around touristing and apart from my early morning jog along the canal we had a restful Saturday.

The start was sunny, it wasn't really hot but was slightly concerning that we were not at all cold despite setting out from our apartment around 8am in mininal race gear and standing around on the start for a full 30 mins. The clothes trucks were timetabled to shut at 8:15 so we didn't use them, in reality they stayed at least until 8:35. For future reference, we could have turned up rather later and had no problems getting to the start on time.

The start was well organised with the main body of runners starting off in three waves, so no-one had huge delays getting going as has happened before (especially Tsukuba for us). I was in the first wave just behind the handful of elites who went off a minute ahead and were soon out of sight.

Despite the limited number of miles in my legs I did think I'vd been running reasonably fast recently (including 25k in sub-3h pace on a windy day), and Vienna is fairly flat, so I had hopes of some improvement over my previous best time which had been on a hilly course with a very thin field. I didn't have any detailed race plans other than to limit my pulse to about 150 over the first half, but had also worked out that setting out at 21 mins per 5k would bring me in at about 2:58 even allowing for a slight slowing. The 2nd kilo had a big downhill so I wasn't all that concerned when I started off a bit quick and my official 5k split times through to 30k were an impressively smooth 20:07, 21:01, 21:00, 21:00, 20:24, 21:00. I knew I was going a bit fast (though not exactly how fast: my Garmin was stupidly set up so it only showed mins not seconds past the first hour, and its calibration was also significantly off from the course markers) but I felt like I was holding myself back a bit, tracking behind runners, hiding out of the wind, taking on lots of water and food (home-made Kendal mint cake) and running quite easily within myself. However by half-way (which I went through in the optimistic time of 1:27:30) my quads were starting to hurt a bit and although I pushed on for a while it all got a bit much and my legs pretty much fell off around 34k. I've never run 8k on such sore legs before and don't intend to again! Lost about 4 mins over the final stages and jogged over the line in 3:00:38, almost a minute down on Chesterfield and feeling very relieved that I got the sub-3h time already so I don't need to have another go.

Not a pretty sight approaching the finish!

The hot sunny day might also have had something to do with my fade, especially after preparing by training though a Yorkshire winter - only a few short weeks ago we were running through snow, Sunday we ran past a shop sign indicating 20C! (Historical met obs say 14C at the start rising to 18C at the end but those are of course for air temp in the shade, which was scarce.) Looking through the results, an awful lot of people seemed to fall apart towards the end, which was probably a combination of the heat and some rather exposed windy sections as the field spread out. Even some of the elite women lost 10 mins or more on the second half, which makes my own +5:38 split seem relatively tame by comparison. Jules had a fairly steady run for her half marathon, also fading a bit in the heat but not as badly as many around her. So although with hindsight I obviously set out a bit too fast, it wasn't by a huge margin. On a cooler and calmer day I might have got away with it. My position of 206 in the men (21st in my age category) would also have been comfortably under 3h on any of the previous 5 years at least.

This time the ribs and beer came after the race, which may have been the real reason for my downfall :-) I'd say more research is needed on this point, but that would imply another marathon which is not on the cards for a while at least. There are three peaks close to where we live in Settle, it would be rude not to visit them some time...

And now we are trying to snooze in lecure rooms, though some of the talks have already been interesting and potentially useful, which makes it difficult!

Monday, April 06, 2015

[jules' pics] Easter in Scotland

Swans, Skunk Cabbage and Rhododendrons

skunk cabbage

Posted By Blogger to jules' pics at 4/06/2015 06:52:00 PM

Saturday, April 04, 2015 Climate sensitivity workshop at Schloss Ringberg

Last year jules went to Schloss Ringberg in Bavaria, for a workshop on cloud feedback and sensitivity "under the auspices of the World Climate Research Programmes (WCRP) Grand Science Challenge on Clouds, Circulation and Climate Sensitivity and with the support of the Max Planck Institute for Meteorology in Hamburg, Germany." (oh, the report on that is just out coincidentally today)

2015-03-24 08.10.42

A follow-up more targeted towards climate sensitivity was arranged for this year, and it seemed only fair for me to go this time. Actually, it was not so much fairness, but rather that the workshop seemed to be somewhat more closely aligned with my work and interests than hers. So although we were both invited this time round, we decided that only I would attend. This ended up with me having the undeserved privilege of two slots for presenting two rather distinct aspects of our research during the week.

I must admit I went with somewhat moderate expectations, as a number of workshops I’ve attended in the past seem to consist mostly of people talking about their own personal interests without really making progress towards shared understanding or common goals. This one turned out to be really good, however. The sessions were arranged into relevant themes and the organisers and discussion leaders did a good job of keeping things focussed around what really mattered for  understanding climate sensitivity. We started with some talks about the framework(s) underlying the concept of climate sensitivity, and some discussion of their limitations. Most significantly to me, this included some strong evidence that the concept of a constant (state-independent) feedback under warming was too limited, with evidence pointing towards an increase in sensitivity with warming, and some difference between forcings. It’s one thing to be vaguely aware of some literature around this topic, but quite another to hear and participate in direct discussion with the people generating the main results. In summary, evidence based on recent obs (ie 20th century temperature trend and energy balance) do on the face of it point towards a rather low sensitivity, but adjusting for the likely change in feedback would push the estimate of equilibrium response up somewhat.

Next up was paleo, where I was due to present what is primarily jules’ work linking past to future. Unfortunately Ayako was also absent, but she did manage to send me some slides (as did Dan Lunt) and so I tried to weave them in to a somewhat broader perspective than I had originally intended. State dependence of sensitivity is a big issue here, though the paleo record does seem broadly consilient with what we see in the models and recent record. It’s hard to see how the climate can have changed as we see in the past if the sensitivity to radiative forcing (in its most general sense) was either negligibly low or extremely high.

The other main focus area was the more process-based understanding of how feedbacks (especially in the clouds, which are the dominant source of our uncertainty) worked in the real world, and how well these were simulated in models. I found this the hardest to follow and certainly couldn’t contribute usefully to the discussion, but there seemed to be a clear feeling that it was hard to justify large negative feedbacks that would bring the sensitivity below about 2C, especially when some positive feedbacks (on top of the well-established Planck response and water vapour/lapse rate feedback) seem to have been identified with some confidence. On the other hand, high sensitivity would seem to require a number of things to combine unhelpfully, which may not be impossible but is certainly not anticipated. There was also a lot of discussion about the absence of extreme models (at either end) from the CMIP archives, and what if anything could be inferred from this. I certainly subscribe to the view that this is some evidence in favour of the CMIP range being reasonable, as firstly it seems quite hard to build extreme models in the first place, and secondly, they tend to behave a bit strangely when they are investigated in any detail. But it is also possible that people converge to some extent through social effects that have no sound basis.

There was a lot of discussion on how to synthesise the different lines of evidence, and my second presentation focussed on this topic. I’m hoping to do more on this soon, as there seems to be plenty of material to revisit and improve the rather superficial analysis that we did several years ago. There are plans to revisit the workshop topics (and venue) in three years to see where have got to, which I look forward to very much. Gavin also has a summary on RC and I fully endorse his comments about the value of meeting in person (though I also think that there’s plenty of scope to expand video-conferencing, especially to enable wider access without the need for lots of travelling). Most of the talks are also on-line for anyone interested.

The food and accommodation was spectacular. The food was far better than one can usually expect in a workshop situation, with a wide range of excellently cooked fish or meat for both lunch and dinner (with the odd bottle of beer thrown in on top). It might have been a little overwhelming for some but I can handle just about anything for 5 days, helped by fitting in a couple of runs down to the lake and back. And I think all attendees found the accommodation very satisfactory too. I think I was a little luckier than some, having one of the big old suites on the first floor. I’ve no idea what I did to deserve this privilege, and was a little concerned on the castle tour, when the first room we were taken into was the one next to mine, and then we walked along the corridor…into the room just on the *other* side of my (embarrassingly untidy) room. Phew. Here it is in neater guise.

2015-03-27 09.00.23

On the afternoon off, we took a cable car trip up a neighbouring mountain, which had some lovely views although not sunny as it had been previously. We also had a touch of snow but nothing like last year.

2015-03-25 15.41.52

And for anyone who accuses academics of hiding away in ivory towers, I can assure you that ivory was nowhere to be seen. Marble, on the other hand…

2015-03-26 18.28.02

Thursday, March 26, 2015

[jules' pics] Mountain Biking

Even I, who am not a great fan of running, admit it has certain advantages over mountain biking when the ground is wet and slippery. Round here the mud is mostly not too thick, but it is quite slimy and the limestone is slick. But we thought that it might not have been raining quite as hard recently, so last week we risked a bit of mountain biking: the Whernside Loop. Only sunk the front wheel of the tandem into mud once. Must have bounced off my handlebar as I still have a huge bruise on my thigh. Then the soles of my shoes fell off. But apart from that we had an excellent time.

Great Victorian enterprise: Ribble Viaduct, with James for scale.
Great Californian enterprise: the Ventana El Conquistador.

But now poor James has had to go and represent the team in Ringberg, Germany where they are discussing climate sensitivity (See #Ringberg15 on the twitter). What you don't hear about on the twitter is about all the official Germanic "fun", eating three very large meals a day, going up mountains, and even, um, singing. Unfortunately I was too busy to attend. My talk was on Wednesday morning which happened to be quite sunny.

Actually, it was't the busy-ness. I am testing a theory about meetings, and it is that it is better if just one of us attends so that we don't spend he whole time conspiring together but instead actually talk to some of the other people. Furthermore, as part time workers without a hoard of postdocs to do our work for us we could easily spend the whole time preparing for, going to and recovering from meetings. And then we'd get no work done at all. And it's slightly less harmful for the planet. Especially this time; James showed not just my slides and his slides but also those from Dan Lunt (Bristol) and Ayako Abe (Japan)!

Posted By Blogger to jules' pics at 3/26/2015 08:06:00 PM

Wednesday, March 25, 2015

[jules' pics] Fountains Abbey

It was dissoluted by Henry the Eighth so is no longer a proper church, but last Thursday we visited Fountains Abbey. Faced by about 15 members of the Cambridge Uni Society of North and West Yorkshire (plus me and James) the tour guide tried really hard to fill the hungry minds before her in the hour long tour. It was all extremely interesting, with the history of the foundation and growth including explanation of the historical differences between common all garden Benedictines and the back to basics Cistercians (Fountains Abbey was the latter), and there were many insights into the daily lives of the monks. Quite a lot has been deciphered by archaeologists analysing the features of the ruins. To me it all looked like piles of stones of many colours (see pretty pics at the bottom of this post), but they can see cupboards and notice boards,  can identify who the sculptures are of,  and even find plumbing. Yes medieval plumbing!

In Japan, quite a lot of religion occurs out of doors, which really is as it should be, but over the hour long tour I grew to appreciate why this is not very practical in Yorkshire. Fountains Abbey no longer has a roof (thanks to Henry, who also realised this was the best way of making the place uninhabitable), and even on  pleasant March day, it got very cold. By the end everyone was hoping that the warm and furry dog that someone had brought along would come to them to be petted.

Walk through the Abbey and you get to Studley Royal Water Gardens and the tea shop. Then walk through the deer park and you get to St Mary's, which, like our house is a Gothic Revival Church.  Unfortunately it is only open from Easter so we couldn't go inside. Some similarities in style between St Mary's and our house are apparent, but St Mary's is really very beautiful. It had a famous architect.

The water gardens may be a historical feat of engineering, but they are a bit dull being just grass and water and statues. There is also a stately home built mostly from stones taken from the Abbey after it was ruined, and a Mill which dates from when the Abbey was a big profit making enterprise. We had only the afternoon so no time to visit these two places. Together all of this is a World Heritage Site. It is a bit strange that Kamakura failed to obtain this status a couple of years ago. Just its water gardens are much better let alone the many temples. 

Posted By Blogger to jules' pics at 3/25/2015 06:13:00 PM

Monday, March 16, 2015 Ten years of GENIE

genie10-17British trains may be slow and prone to delay, but they are the main reason that British people are so ingenious. Harry Potter was famously dreamed up by JK Rowling on a train. And similarly, it was on a train that the idea of the earth system model we now called GENIE came into the  mind of JG Shepherd. JGS then (1998/1999) started to try to get people interested and gathered a group of apparently bright early career researchers (which means none of them had permanent jobs) from around the universities and NERC research laboratories. 

James and I were the two representatives from the Proudman Oceanographic Laboratory, and this was how we started the move into climate research. Proposals for funding were made, but none of the actual workers, with their unstable positions were eligible to be on the grant, and despite its list of many illustrious principal investigators, it wasn’t funded. The early career researchers dispersed around the world, to USA, Switzerland and us to Japan (a couple also stayed in the UK). Curiously, however, the work on the model (then called GOLDSTEIN) continued, and by the mid-noughties we were all churning out lots of papers based on it. After this, it got some funding through something called “e-science” which was all to do with computer science and internet wormholes and stuff. The money mostly seemed to fund computer scientists to do strange things that we didn’t understand to the code, while the rest of us just carried in working with the model without any extra funds. It was at this point that the model was rebranded as GENIE.

Also in the mid-noughties, it was through the GENIE emailing list that several of us decided it would be a good idea to start a journal devoted to descriptions of models. I suppose as new interlopers in the climate modelling world we were shocked by what we found, in a way that someone “nurtured” into the dark arts of modelling through their PhD probably wouldn’t be. We found that not only were models not described in journals in a way that would make them anything close to being able to be reproduced by someone else, but also that when we tried to publish the fruits of our hard labour of model development, the papers got rejected, or received severe instruction to cut the amount of model description and increase the results. As basic scientists, used to properly explaining our scientific methods in our papers, we were horrified! Thus was the revolution started that became the journal Geoscientific Model Development. I don’t know if it is universal, but certainly bosses these days are much less likely to encourage their modellers to sweep their work under the carpet (= shoddy internal documents). Instead they encourage them to write papers.

For reasons no one can fully comprehend, Andy Ridgwell recently decided to hold a GENIE party to celebrate the past present and future of GENIE. He said it was something to do with 10 years of GENIE, but it is many more years than that since JGS got us all together. The party meeting was held last week in a nice old building in Bristol University. Almost all the original ones were there (I think only James was missing) and all except me and James now have very important jobs (mostly full professors) at UK universities. I think James and I just got spoiled by having so much fun in Japan so long!  Although about half the people in the room were female I was surprised to notice that I was the only female one of the originals! So there are certainly more women in climate science these days. But I find it really concerning that there are still so few women at the higher levels.

The day included talks on the history of GOLDSTEIN and GENIE, and ongoing work in the biogeochemistry and physics fields. It was really interesting to me, as in around 2007 we gradually stopped using GENIE and started using the MIROC GCM and then the CMIP ensemble. There was also a very entertaining talk by Gethin Williams who is a computer scientist at Bristol Uni. He pointed out that GENIE was efficient neither in terms of vectorisation nor parallelisation and while apparent computer speed continues to increase at roughly Moores Law pace, GENIE still runs as slowly as it did in around 2005. (ROFL!!!) I was quite surprised, and really wondered what all the e-science funding had been for, as this kind of optimisation was really important at our old laboratory in Japan (due partly to the requirement to run models efficiently on the earth simulator). James loves making efficient algorithms, and even knows how parallelise code, so has offered his services, should anyone in the GENIE team ever be able to afford him.

I took quite a few pictures. I wanted to document the ravages of time upon the GENIE men. Unfortunately most of them are active sorts of people, and don’t really look much older! I ended up taking photos of all the people who gave talks as well as the oldies, and there’s a whole album on flickr: CLICK HERE  to view.

top: Andy Ridgwell
bottom: Neil Edwards and Bob Marsh)


Wednesday, March 04, 2015

[jules' pics] Cat update

Someone (Steve Bloom) asked after the the foster cat. I think Riley is now pretty much living the life of Riley. He's adjusting quite well to home life, and is now awake and playful in the mornings, becoming more peaceful in the afternoons. He's more settled. Only in the last few days did he get brave enough to snooze on rather than behind chairs. Now he like to position himself rather regally, centrally positioned on a chair or cushion. He still does not fully appreciate that toys are for chasing and hands are not, which is not fantastic when he gets very excited. But he's improving. And is actually now not all that bad at playing fetch, considering that he couldn't do it at all a week ago. Shockingly, he didn't seem to mind when I slipped a harness on him today.  Let me know if you'd like to adopt him! I reckon he needs an equally rambunctious cat friend as well as a new owner, but people tell me that cats often do not get on when newly introduced to each other as adults.

12 March, update: Good news! Riley has a new home! Someone visited yesterday and liked him tremendously. She's looking for an interactive cat to keep her and her husband entertained working from home, and also for her son. Apparently their last cat was barely touchable. They should enjoy Riley then! The other news, however, is that she can't take him until after Easter so we get to keep him for another month.  He will have been here 3 weeks tomorrow but he's still changing;  I write this with him sleeping on my lap, which is the first time he's done so...

Posted By Blogger to jules' pics at 3/04/2015 07:42:00 PM

Tuesday, March 03, 2015

Climate change by numbers the title of an interesting TV programme that was on BBC 4 last night. It is quite amazing that they dared to show such a maths/stats/science-heavy program at prime time, albeit on a minor channel, so I will start by commending them for that (the inevitable grumbles follow later). The three numbers they featured were the 0.85C warming since 1880s, 95% confidence that anthropogenic influence had caused most of this, and the 1 trillion tonnes of carbon that would take us to about 2C warming. I think it was originally planned to be three 30 minute programmes, but they ran it all together as one long piece, which seemed to work well to me.

I think they told the stories in an engaging manner, there was also lots of interesting historical stuff about how our understanding of the climate system has developed, which was mostly very well done and would probably have been even more interesting had I not already known it! But of course I was hardly the target audience.

In fact one of the researchers making the program contacted me last year to talk about Bayesian vs frequentist approaches to detection and attribution, specifically the IPCC's statement attributing most of the warming of the last century to anthropogenic effects. Unfortunately I wasn't able to be very encouraging about the idea of explaining the differences between Bayesian vs frequentist approaches to the general public, after all most climate scientists struggle with this question as is demonstrated by the IPCC's misrepresentation of D&A results! I've written on this (really must update my web pages, that link won't last for ever...or will it?) but the argument has little traction even in the climate science community because most people are quite content to continue in their comfortably-erroneous way.

Anyway, the Bayesian thing didn't make it into the transmitted programme, which I was neither surprised nor disappointed about, as I really can't see how to present it in such a way that the general public would get anything out of it. And the traditional misrepresentation of the probability of observations more extreme than observed given the null, as the probability of the null given the observations, was heavily featured (that's basically where the 95% comes from). Sigh. But what I really want to grumble about most strongly was the garbled and nonsensical representation of Kalman filtering in the first section, which, contrary to the claims in the programme, is not a method to check observations against each other and has not been used for temperature data homogenisation. The Kalman filter is actually used for updating a model prediction with new observations, and this is how it was used for space navigation. That is, based on current estimates of velocity and position at time t1, the equations of motion are used to predict the new position and velocity at subsequent time t2, and then imperfect observations of the position at t2 are used to update the estimates of position and velocity, and so on ad infinitum.

Ok, pedants may observe that NCEP has pioneered the use of an ensemble Kalman filter for its 20th century reanalysis project, but this is somewhat tangential to climate change and their results, interesting as they are, have their own homogenisation problems and are are hardly central to the debate on global warming. Ironically, Doug McNeall (who was involved as a scientific consultant, I'm not blaming him for anything in particular though) tweeted a link to the wikipedia page on Kalman filtering, which is a much better resource for anyone interested in learning more about the topic. Anyway, I'm really baffled as to where this bit came from - maybe they just couldn't resist a link to “rocket science” :-) Or did someone think “filter” might be related to filtering out bad data? Well, it isn't.

The “pixel sticks” were very clever, but I don't really think a line graph is improved by drawing it on wobbly axes, expecially if a straight line trend is then drawn through the data! I wonder if Doug will feature that on his Better Figures blog :-) And as for the presenters spending most of their time walking away from the camera...I'm probably sounding like a grumpy old man so I'd better stop. As I said, I think it was pretty good overall, but if you want a mathematical/statistical program that really doesn't make any concessions to dumbing down, and that does cover climate change (and Bayesian statistics) on occasion, I strongly recommend “More or Less” on Radio 4.

Update: Oh, this is interesting. It's a blog post about the programme from the mathematician (Norman Fenton) who presented the 95% section. Turns out he is actually a Bayesian who clearly understands how that number is tarnished by prosecutor's fallacy, and he argues that the scientific debate would be improved by a greater use of Bayesian methods!