Feedback: Listen with words not numbers

April 16, 2014
Feedback affects us

Feedback affects us (Image from Wikipedia)

Feedback is a modern word describing the process of assessing whether an enterprise (a business, a car or a country) is in some sense ‘on course’.

  • Negative feedback is the most valuable feedback – but rarely the easiest to deal with.
  • Positive feedback is always pleasant – like being stroked – but is often difficult to distinguish from politeness.

But whether it is positive or negative, genuine feedback is like gold-dust.

So at Protons for Breakfast we take great care to get as much as we can. We take extensive open-format feedback each week and show people that we take it seriously by replying to every note, no matter how apparently trivial.

And at the end of the 6 week course we collect final course feedback.But rather than offer people 5-point tick boxes, we instead create the time and space in which people can write sentences.

I am convinced that people’s choice of words communicates more powerfully than a numerical metric, even if it can’t be easily graphed or expressed as a statistic.

To try to convince you of this I have listed edited highlights below, or you can download the unexpurgated version here.

Like many science communicators, I take what I do ridiculously seriously. And the thought that it touches people’s lives is almost unbearable poignant.

The feedback below moved me to tears. But knowing that “86% of the people were ‘very satisfied or satisfied’” would leave me cold. See what you think.

Feedback from the 19th presentation of Protons for Breakfast

One thing you learned…

  • Generally that atoms and molecules are the key to understanding physics and I hadn’t appreciated that at school – so I didn’t get very far!
  • That global warming is real, actually happening.
  • Electricity is everywhere.
  • How mobile phone signals are transmitted through base stations.
  • I now know what makes up an atom.
  • About how a nuclear power station works.
  • There are atoms everywhere.
  • E-L-E-C-T-R-I-C-I-T-Y.
  • Everything is made up of atoms and electrical fields.
  • That absolutely EVERYTHING is electrical. (and more, but it said ONE thing).
  • I have learned more about how atoms work.
  • How paper is picked up by a balloon.
  • How small we are in the universe. Greater understanding of atoms and various other things.
  • An appreciation of the complexity behind simple things I take for granted.
  • I have learnt that atoms are all around us!
  • Magnetic properties as atoms! Best explanation ever! And I have a 1st class honours in Physics.
  • What nuclear fusion is.
  • Everything you look at is absolutely full of atoms, moving without us realising it!
  • How my phone works and how complicated it is. That we should try to prevent carbon dioxide from getting into the air to stop global warming.
  • WOW so many things. Particles are the basis of all science. To think about stuff I take for granted with more wonder. Not to always believe science in journalism/media.
  • The electric force is to blame for everything!
  • I have learnt my phone produces microwaves.
  • Everything is a wave! That the ‘gap’ between protons neutrons and electrons is just a gap, but an important gap.
  • Fields are everywhere.
  • Everything is made out of something.
  • I have learnt that electricity is essential to live and it is everywhere.
  • There is electricity in sausages.
  • Better understanding of how waves/atoms/electricity all fit together. Even heard about Brownian motion over the weekend and I knew what they were talking about.

One question you still have…

  • If global warming is an imminent disaster, why is big business in control of energy production for profit? (The less energy we use the move we pay per unit?).
  • Nothing I can think of, the excellent option to write feedback each time has answered it!
  • We can adapt to increase in temperature (grow vineyards in Scotland). Don’t fight it, work with it.
  • How does solar power work without direct sunlight (e.g. clouds in the way)?
  • What’s the problem with nuclear fusion?
  • From week 5, how do we know that phones are what may give us cancer, is it maybe something that people who use phones also do?
  • If so many things are ‘a bit’ radioactive what is the defining feature of ‘bad’ radioactivity? Where do gamma rays fit in?
  • Why do we never see the dark side of the moon?
  • Why is the earth’s centre magnetic? (North/South).
  • Who shot Kennedy?
  • What made you want to run a science course like this?

Is there any message you would like to give to the NPL management team…

  • Thank you for the enjoyable evenings.
  • Thank you!
  • Cheers!
  • Thank you – well run, organised, clean and efficient. Really needed tea and the copious quantity of biscuits that you provided.
  • Yes, double this man’s salary and send him on a tour of Britain giving the rest of the country the choice to enjoy and learn.
  • I wanted to submit a question re: this course. I couldn’t find a contact method. I think I sent a message on a blog-thing. (Not sure!).
  • This course is excellent, if Michael is unable or unwilling to continue is there anyone else who could run it? – Loved the course – beautiful surroundings (buildings) and you have truly spoiled us with all of the tea and biscuits.
  • The NPL is the most amazing place – long may it continue!
  • Well done.
  • It is a great resource. I have enjoyed it tremendously.
  • You’re doing well!
  • Keep up the good work – great fun!
  • Well done – more please!
  • Great computering skills.
  • I would like to thank Michael and the team for all their hard work during this course, thank you very much. Very entertaining and boggling every week. J
  • Thank you very much for improving my scientific knowledge.
  • No.
  • Make a sequel e.g. Electrons for Lunch.
  • Thank you!
  • My daughter is looking forward to coming in the autumn with my husband – I know she/they will really enjoy it.
  • Excellent course and facilities. Great enthusiasm from Michael.
  • Thank you for allowing me to attend such an organised and interesting course.
  • Well done, the course is great.
  • Keep doing Protons for Breakfast.
  • Really good job! The technical issues with the powerpoint seems to be fairly frequent in the 1st half of the course though. But Michael dealt with it really well and the flow was maintained.
  • Very well delivered course at such an affordable price. We home educate our daughter and chemistry and physics are subjects that are really hard for her to do. After the session at NPL she was coming home and wanting to learn more and do the experiments. Thank you.
  • This course is a fantastic way to spark an interest in science for young and old alike. Thank you.
  • This is a really good course and it would be a shame if it stops L
  • Thank you.
  • Well done. Very informative. The questions and Michael’s answers – very good!
  • Thank you JJ
  • Thank J
  • Keep doing this!
  • Wonderful staff and helpers. Excellent refreshments!
  • Please have more open access Science courses – they are very inspiring. You have so much here to show people.
  • Wonderful course. I hope when my youngest grandson is old enough it will still be running.
  • Thank you J!
  • Really well organised course. Very helpful and friendly staff. I would love to attend more like this.
  • Please keep offering this course. The presenters and helpers have made an enormous amount of science interesting and accessible for young and old in the audience.
  • This is a fantastic course for parents, children, teachers – everyone – to learn about the physical world. It was also great to see what passion and creativity there is inside NPL.
  • Very inspiring!
  • It is great that NPL provides this course for the interested non-experts to learn from the experts.
  • Well done.
  • Keep up the good work.
  • Well done for running an excellent course, for a wonderful mixture of people.
  • Well done!
  • Well done. Try to make it a bit more interesting for kids.
  • You just need to carry on what you are doing. It is great fun and people learn a lot.
  • Parking an issue – could you make it easier to get from other half of site to here?
  • Many thanks for a super course.
  • Just a fantastic course – I would recommend it to anybody (and do regularly). Thank you to everybody.
  • Thank you it was great. Really enjoyed the biscuits! Especially when there was Jaffa cakes! (my favourite). I don’t think I’d tried a wagon wheel until now and I LOVE THEM!
  • More resources for understanding what NPL does – website, You-tube etc. Great resource for kids to get interested in Science.
  • Well done!
  • THANK YOU!!!! I love it soooo much.
  • Keep up the fun and fantastic way of getting science to us all. Well done to you all and keep it up.
  • Very impressed with the standard of this course in many ways: teaching skills of presenter; super balance of theory and demo/ very large amount of info communicated/ high standard of visual/demo/experiments/really impressive experts in the last half of the course deployed well.


Children OnlyAside from the biscuits, ice cream and jelly babies, what did you like best?

  • I enjoyed the debates.
  • The experiments – both doing and watching (+ jelly babies and ice cream).
  • Hovercrafts and wands. Live experiments – watching and doing.
  • Hovercraft.
  • I like the exciting demonstrations.
  • Having an advantage in GCSE physics.
  • Learning about nuclear power.
  • The demonstrations that were done.
  • Killing of the egg in the microwave.
  • All of the above.
  • The crazy experiments – egg in microwave, wobbling water in pan, electrocuted gherkin, etc.
  • I loved all the demonstrations and Michael’s enthusiasm!
  • I loved the whole course in general as I felt it has contributed hugely to my confidence and understanding of science in general. I thoroughly enjoyed my time at NPL.
  • I’m not sure, everything is great.
  • All of it! But if I had to choose it would be using the microwave to cook CDs and eggs, that was a lot of fun.
  • The knowledge that I gained.
  • Practical activities.
  • The practical experiments.
  • I like the session covering heat.
  • The experiments!!!
  • Week 2 – light.
  • Watching the demonstrations and experiments, they helped me understand how different chemicals/atoms react.
  • Demonstrations!
  • The demonstrations of the experiments.
  • All the experiments.
  • The exploding egg.
  • Hovercrafts.
  • The egg and the gherkin / everything.
  • The fact I was able to easily broaden my knowledge of science. It had a strong, positive effect on my GCSEs.
  • Learning about mobile phone radiation.
  • The demonstrations.
  • The experiments, more please!
  • Hovercraft and egg.
  • I liked it when the experiment went kind of wrong and the egg exploded.
  • Experiment when ice cream was made.
  • Everything, because science is fun.
  • Environment.
  • The lectures and demonstrations.

Teachers & Trainee Teachers Only Please state one way in which you feel this course has helped you

  • I think it is essential to have a greater knowledge than the children I teach – just in case I get tricky questions, at least I will have the tools for us to find out together. Must download songs!
  • See previous – mainly how to make physics more relatable and easier to understand for the less scientifically minded.
  • Some excellent demonstrations.
  • Mike has a great method of teaching. Lots of passion – however course hasn’t really help, obviously aimed at children.
  • It tackled topics that are relevant to the children, answering questions they normally have in class.
  • Having to teach my daughter subject content I haven’t attended in years is tough. This course helps me have greater understanding and delivery of my daughter’s lessons and questions.
  • To communicate quite complex ideas more simply/better.
  • Experiments to demonstrate particular topics.
  • It explained climate change which I cover as part of Year 5 geography (Science taught by specialist in current school.) Has helped me a lot with some science basics which I was missing before – if I return to primary teaching where I need to teach science I will feel more confident/worthy to do it!



Feynman Diagrams are Maths not Physics

April 13, 2014
A Feynman Diagram such as the one shown above is a succinct way of summarising a mathematical calculation. However, even though it looks like 'cartoon' representation of the physics, it does not describe the physical process.

A Feynman Diagram such as the one shown above is a succinct way of summarising a mathematical calculation. However, even though it looks like a ‘cartoon’ representation of the physics, it does not describe the physical process.

After giving a talk to A level physics teachers the other weekend, I stayed around to listen to a presentation about radioactivity: it really is a pleasure listening to other people teaching!

From my disinterested perch at the back of the class I was surprised to find that the process of beta decay was described by means of a Feynman Diagram.

I was then even more surprised when teachers asked detailed questions about which type of ‘vector boson’ was involved. I began to wonder how this could make any sense to ‘A’ level students. Do they really know what a ‘boson’ is? Or a ‘vector boson’?

And an e-mail today from an AS level student asking me about these diagrams crystallised my misgivings: I realised that teaching and examining this kind of thing as physics is potentially quite misleading.

At the heart of the matter is the fact that Feynman diagrams represent an ingenious way of describing a calculation: they do not describe the physics underlying the process. You can read an excellent article about their history here.

Let me explain:

  • The diagram at the head of the page describes the way that the electrical interaction of two electrons – their mutual repulsion – is calculated in an advanced theory called quantum electrodynamics (QED). The lines and vertices each have a precise mathematical interpretation.
  • QED describes the repulsion between the electrons in terms of the exchange of an infinite number of ‘virtual photons’. The diagram above summarises the way the exchange of a single ‘virtual photon’ - the wiggly line in the middle – is calculated.

Now QED is an astounding theory. It has been checked thoroughly and there is an astonishing correspondence between the results of its calculations and physical reality. In other words it is in some sense ‘correct’.

But nonetheless there are two problems when using these diagrams in schools.

  • Firstly I underlined the word ‘infinite’ in the bullet point above because when you see that word you can be sure you are in the realm of maths, not physics. This is because there are no infinite quantities in physics.
  • The second problem is that it involves the concept of a ‘virtual photon’. Despite 35 years of exposure to this concept – I haven’t a clue what it means physically. I suspect strongly that its role is calculational rather than physical.[I searched for a comprehensible 'link' but there are none! Try this as a typical example.]

Some people might argue that because ‘virtual photons’ are part of the way QED works, then the accuracy of QED is in itself evidence that virtual photons ‘exist’. To these people I have a one word rebuttal: ‘Epicycles‘: just because a calculational technique improves predictions does not mean that there is a physical counterpart to the ‘calculational entities’.

Now why does any of this matter?

It matters because this stuff is being taught for all the wrong reasons. It is being taught , I guess, because it looks like  a cool cartoon, and also requires no numerical skills. We are asking students to simply imitate the marks made on blackboards by other physicists.This is bad.

Further, its inclusion has caused the exclusion of a really interesting feature of beta decay that students could appreciate directly.

Instead of electrons being emitted in the same way as alpha particles are - with a single characteristic energy and momentum, electrons emitted in beta decays have a wide range of energies, from a maximum characteristic value, all the way down to zero.

In the early days of nuclear physics this spectrum was puzzling because it seemed as though beta decay did not conserve energy or momentum. ‘A’ level students can readily appreciate both these conservation laws, and the potential significance of them being broken.

And the resolution of the apparent breakdown of the conservation laws was that there was a third particle involved – a particle with almost no mass called a neutrino. And the existence of this particle – not to be directly detected for 25 years after its existence was hypothesised – was based on the law of conservation of momentum.

So these diagrams look like physics, but they are not. And IMHO they don’t belong in an ‘A’ level physics syllabus.


Who is going to die in 2048?

April 9, 2014
Age Standardised UK Mortality

Graph showing Age-Standardised UK Mortality per 100,000 of population per year. In 2010 mortality was around 1100 per 100,000, so for the UK population of 60 million we would expect around 660,000 deaths per year. However if the trend continues, no one will die in 2048!

While investigating causes of death in the United Kingdom, I came across the data above. The graph shows that the age-standardised mortality in the UK has been falling since at least 1980 – and shows no signs of stopping.

Indeed, if the trend continues, then sometime around the 14th March 2048, mortality will reach zero and no one will die in the UK!

Now of course, although this data is real and correct, the trend can’t possibly continue indefinitely. But the data is nonetheless fascinating for at least three reasons.

Firstly, in the face of seemingly endless stories telling us all how unhealthy we are – it seems that the trend to lower mortality is continuing unabated, despite the obesity ‘crisis’.

Secondly, although the linear trend in the data is striking, we have no justification for extrapolating the trend into the future. Why? Because its the future! And we don’t know what is going to happen in the future.

And finally, these numbers give us a scale for considering the relative seriousness of different causes of death: that was the reason I looked up the data in the first place.

I read that air pollution causes 30,000 deaths a year in the UK and that seemed a surprisingly large number. From the graph we can estimate that mortality in 2014 is approximately 1000 deaths per 100,000 of population per annum. So that that for the UK population of 60 million, this is about 5% of deaths – which still seems shockingly high, but is a smidgeon closer to believability.

So good news all round: especially if you, like me, are a man. The mortality of men and women is shown separately below.

If the trend continues, then after millennia of ‘excess male mortality’, the mortality of men should fall below that of women in approximately 2027 and reach zero in 2042 – before the women – who will not attain immortality until 2060!

Age Standardised UK Mortality by sex

Graph showing Age-Standardised UK Mortality per 100,000 of population per year for men and women. If trends continue, male mortality will fall below female mortality in 2027 and no men will die at all after 2042!


Dave asked: Are you sure age standardised mortality means what you think it does? Age standardised mortality might drop to zero. But that is not mortality. If the plot showed mortality that would suggest life expectancy has doubled since 1980, from 50 to nearly 100.

And I replied: The calculation is this:

  • How many people died in a particular year aged (say) 69.
  • This number is then expressed as a fraction of the actual UK population who were aged 69.
  • This is then expressed as an actual number who would have died in a ‘standard population’ called the European Standard Population.

This procedure allows the relative mortality in different countries to be compared

So, if for example, the UK has a high absolute mortality for 69 year-olds, but not many 69 year olds – then this will produce a larger number when ‘age standardised’.

I have obtained one or two sets of actual death data – but I don’t know the equivalent population to divide by to get the absolute mortality per 100,000. However this data shows a similar trend with roughly the same intercept.

What does it mean? I don’t know! I think it means that we are living longer (Is that news?). I was just struck by how straight the line was and how it begged to be extrapolated!

Science Demonstrations: the art of seeing things differently.

April 6, 2014

One of the highlights of the last few weeks was attending the premiere of Demo: The Movie by Alom Shaha and Jonathan Sanderson.

Mingling with the gliterati of the science communication world, the event, the conversations, and the film all helped me to reflect on the purpose of science demonstrations.

To me the purpose of a demonstration is to highlight one aspect of the everyday world, and to allow us to look at it ‘differently’.

This is necessary because for most of us, for most of our lives, the world doesn’t seem mysterious: our world comprises familiar objects that behave in a familiar way.

So famously in 1848 Michael Faraday gave a series of six lectures about an object which must have been extremely familiar to his audience: a candle. And this ground-breaking lecture series is the starting point for Demo:The Movie.

From this point Alom, a teacher, travels from his classroom to San Francisco via the western deserts of the USA performing demonstrations and reflecting on the their role in teaching as he travels.

He concludes that performing a successful science demonstration is an art which incorporates elements of stage magic, understanding of teaching aims and objects, and that most difficult to pronounce word, pedagogy.

For me the most important point made in the film is the profound (and paradoxical) point that demonstrations are different from videos of demonstrations.

This point is made by showing a plastic bottle (which you previously saw Alom fill with air at the top of a mountain) has been crushed when he reaches Death Valley, exactly as viewers probably expected.

But Alom points out that seeing this on video, you have no idea whether this is the same bottle you saw filled earlier. Indeed, you have no idea whether that it was even ‘earlier’.

It is the power of seeing things for yourself which is personally challenging. In terms of my own favourite demonstration, anyone who has ever seen a sausage attracted to a balloon is in some way personally challenged to ask themselves’ What is going on?’.

I can strongly recommend this 30 minute epic to anyone who engages in science communication in any form, but most especially to teachers who might feel inclined to simply show a class a video of something happening instead of performing the demonstration themselves.

And if you want help on performing demonstrations and tips on ‘getting it right’ Jonathan and Alom have created a website which has many videos showing you how not to use videos in class!

Finally, if you love the movie as much as I do, you can check out the bloopers movie/trailer below.




April 5, 2014

The inimitable Tom Glazer and Dottie Evans sing about electricity

What with finishing the 19th presentation of Protons for Breakfast, and giving three weekend training sessions to teachers, I have found myself over the last few weeks with no time to think. And no time to think means no time to blog. :-(

But now, with the course over and arrival of the lighter evenings I feel freed to think again – and write!

This presentation of Protons for Breakfast was the busiest yet, and I am grateful to my colleague Dale Partridge for evidence that our work is finally leaking into mainstream consciousness.

One of our main aims is to change people’s appreciation of electricity. And indeed we aim to change not just how they think about electricity, but how they pronounce it.

As anyone who has attended the course knows, electricity is pronounced: eeeeeee-lec- tricity, a bit like this:

And it surely can’t be a coincidence that the latest hit by the The Pierces adopts a distinctly similar pronunciation.

Admittedly, the pronunciation by The Pierces lacks the bright, upbeat tone of Tom Glazer, but it is not bad for youngsters.

[UPDATE: My colleague Roberto Gavioso brought this interesting pronunciation by Captain Beefheart  from the 1960s to my attention

It is a little darker than the Pierces, but is clearly influenced by Glazer’s seminal work. The fact that it was not a hit at the time is surely because Protons for Breakfast had not yet influenced the zeitgeist. END OF UPDATE]

Now I am just going to flip back through my notes for the last 6 weeks and remind myself of all the topics I meant to write about.

Happy Listening. The Pierces song is below but the important part is about 1 minute and 10 seconds in. I haven’t listened to the song all the way through, but it doesn’t appear to be about physics at all!


Some things to look forward to…

March 1, 2014

Swansea lagoon visitors centre

Swansea lagoon visitors centre. Picture from BBC News.

‘News’ is frequently an abbreviation for ‘Bad News’. There seems to be no end of stories about ‘things’ getting worse.

And so it is something of relief to hear of people providing solutions to our problems. Here are few things which have recently inspired me with hope.

  • Meeting some teachers today.
  • The Swansea Lagoon Project in Swansea.
  • The Solana and Ivanpah Solar Thermal Power projects in the western USA.

Teachers: Today, Saturday March 1st, I got up early and drove to Birmingham to give a talk to a group of eight physics teachers at a training day.

They were a friendly and positive bunch – but what inspired me was not their subject knowledge (which was actually excellent) but their looks. To my 54 year-old male eyes these people didn’t look like what I expected physics teachers to look like.

From this gender-balanced group there was short and tall, thin and chubby, and a range of ethnicities. They were united only in an interest in Physics and in teaching it well.

As I reflected on the long drive home, it seemed as though these people were part of the solution to a long-standing problem in physics education, and I felt honoured to be able help a little.

The Swansea Lagoon Project (BBC Story) may or not get built, but I loved the design flair in their visitors centre (main picture above), and modesty of the project.

This is not the Severn barrage which would block the entire Severn estuary and which would be able to supply 5% of UK electricity demand to the detriment of nobody but a few wading birds.

This is a much more modest lagoon off the coast of Swansea which would not even harm the birds! Its lower cost makes it much more likely to actually get built, and the technology is scalable – multiple projects could be developed one by one – something which also makes it much more investment friendly.

Map of the Swansea tidal lagoon

Map of the Swansea tidal lagoon

Two solar thermal projects in the US have recently begun operating.

  • The Ivanpah plant consists of an astonishing 170,000 parabolic mirrors each of which tracks the Sun to focus light onto a furnace at the top of gigantic tower. This heats steam which drives a turbine to generate electricity.
  • The Solana plant in Arizona is similar, but distinctly different. One difference is that it uses cheaper parabolic troughs to heat a synthetic oil which runs along a tube at their focus. But this plant can also generate electricity after dark! This astonishing engineering ‘trick’ involves storing the thermal energy in gigantic vats of molten salt. The heat can then be used to generate electricity after the Sun has gone down, allowing the generation of electricity at its time of peak demand.

These plants have been heavily subsidised. But they show that this technology is practical and I am sure the next generation of plants will be cheaper to build and operate.

However the LA times reports today that solar thermal plants are already obsolete – even as they open! – because the falling cost of silicon photovoltaic plants is making them uneconomic. That may be true – but photovoltaics definitely don’t work in the dark!

The future is not obvious. But when I see the diversity of people teaching physics and wanting to do it better. And when I see the range of emerging options for sustainable energy generation I feel able to hope that even if I don’t recognise it immediately, the future will arrive all by itself – and that it will not be all bad.

Protons for Breakfast 19 is about to begin…

February 23, 2014

PfB Logo

The nineteenth presentation of Protons for Breakfast is imminent, and so a cascade of preparatory activity has begun.

  • I have read through and responded to ‘questions’ and ‘reasons for attending’ from the 130 people who have signed up.
  • I have revised the PowerPoint files for Week 1 – somehow still finding things to improve.
  • The NPL security staff have been notified
  • The facilities team have been asked to makes sure the air conditioning stays active late on the relevant evening.
  • And the biscuits have been ordered by the catering team.

So I guess that is about that. What can possibly go wrong?

There were a couple of amusing reasons for attending:

  • Accompanying Grandmother
  • Made to come by parent.

And quite a few insightful questions. Several people wanted to know either when we would have ‘proof’ that Global Warming had an anthropogenic origin, or when we would pass ‘the point of no return’, or why people weren’t ‘more concerned’. But a lot of questions were simple puzzles:

  • How do we know there are more stars in the Universe than grains of sand upon the beaches of the Earth?
  • Why do we feel colder when the wind blows?
  • Why does hot water freeze faster than cold water?
  • What is a HD Picture?
  • How do quantum computers work?
  • Can protons become neutrons?
  • Why do our stomachs ‘rumble’?
  • Will the universe ever be totally dark when all energy has been lost?

And many more. I love the diversity of these questions.

Having run these sessions for 10 years now I am constantly surprised at how each group has its own personality.

And I am very much looking forward to getting to know this group and the individuals within it.

By the way, while the course is on, the frequency of blog articles generally declines – sorry: it’s just all I can do.

Happy Birthday Ludwig Boltzmann

February 20, 2014
Happy Birthday Ludwig Boltzmann.

Happy Birthday Ludwig Boltzmann. My colleagues at NPL ate a ceremonial cake.

Last week I spoke with Ludwig Boltzmann’s great grandson: it was an honour and a pleasure.

Gerhard Fasol had e-mailed me to ask for details about plans to re-define the SI units of temperature (the degree Celsius and the kelvin) in terms of the Boltzmann constant.

Gerhard has a fairly impressive scientific CV in his own right, but of course his great grandfather’s legacy stands above his achievements and most other scientists. If there was a Premier league of scientists, he would be in it.

Boltzmann’s essentially took the ‘idea’ that atoms really existed, and turned the ‘idea’ into a detailed theory of matter with quantitative predictions and brilliant insights.

His ideas were not immediately accepted, which in retrospect makes his achievements all the greater. His motto was apparently

Say what is true;
Write the way that it is clear.
And advocate it until it is your opinion!

Physics has several ways of acknowledging the achievements of its ‘stars’. Their name can be used for an Equation, or a unit of measurement, or a fundamental physical constant. These honours are the scientific equivalent of having one’s paw-print set into the walk of fame.

And Boltzmann has a constant, k or kB, according to fashion, describing the link between temperature and energy. Scientists use this constant every day making his memory immortal, and raising his image to an almost mystical level

So speaking with his real great grandson was something of a shock! It reminded me that even ‘great’ people are people too, and I was happy to celebrate his birthday (he would have been 170) with my team today.

And we were very fortunate that Tesco had a suitable cake in store – what are the chances of that?

Flooding and Climate Change: What have we learned?

February 17, 2014
The River Thames in flood last weekend. As I write, the water level has called by around 20 centimetres.

The River Thames in flood last weekend. As I write, the water level has fallen by around 20 centimetres. What lessons have we learned?

As the flood waters slowly recede, can I be the first to congratulate the Environment Agency?

We have just experienced the worst sequence of weather events for a few decades or a few centuries. And almost nobody was hurt, and only a few thousand houses were flooded. That has to be a pretty good result.

Although these events cannot in any way be linked to Climate Change, there is still a lesson to be learned in that regard: and that is that we are vulnerable.

If the future climate changed so that such weather was more normal – then we would be have to adapt and there would be real costs (financial and otherwise) involved. And if the weather changed more dramatically, then the consequences could easily be more significant.

Now you may think that following Julia Slingo’s comments to the media that there is a link toClimate Change. So I read the Met Office’s 27 page media briefing on ‘the recent storms’ with interest. It reads like a police report of a pub brawl. But instead of:

  • A hit B because B said’s A’s girlfriend was sleeping with C.
  • C screamed and hit A who then attacked D who fell over and hit the bar.

We have:

  • Excess rain in the tropical Pacific affected stratospheric winds
  • These winds made tropospheric storms across North America move southward drawing air from the warm Atlantic etc. etc.

And then after 26 pages the report concludes

… it is not possible, yet, to give a definitive answer on whether climate change has been a contributor or not. 

So let’s put that particular baby to bed: in 30 years time when we look back we will see whether this event was part of a trend or merely a blip – but at this moment, we just don’t know.

And when in 30 years we look back, what will we say?

  • Will we say ‘Thank you’ to ourselves for considering the  possibility that this could be start of a significant change?
  • Will we be grateful to ourselves for updating our flood defences, and adapting our farming and flooding strategies?
  • Will be glad that the extra money we spent saved lives in the many storms which followed?
  • Or will we regret spending the money because – as things turned out – there were no major floods since.
  • Or will we look back and say ‘Great’ we got away with that – we have had 30 years without flooding?
  • Or will we kick ourselves for not acting when we could have done.

Whatever we want to be thinking in 30 years time, we need to act to achieve it now.

How good are climate models and climate forecasts?

February 12, 2014
Figure 10.1 (b) from the IPCC 5th Assessment Report shows the results of climate calculations ignoring the effect of human-induced climate forcing due mainly to carbon dioxide.

Figure 10.1 (b) from Chapter 10 of the IPCC 5th Assessment Report. The red line shows the results of calculated change in global mean surface temperature ignoring the effect of human-induced climate forcing due mainly to carbon dioxide. The black line shows our observations. We conclude that we cannot understand the Earth;s climate without account for human-induced Climate Change. If only we could go back to the 1960′s and make different choices…

Modelling the interactions of the ocean and atmosphere to predict the future climate of the entire Earth is one of the most breath-taking achievements of modern science. The sheer chutzpah of the endeavour is inspiring.

And much of the debate about the impact of climate change centres on the reliability of these ‘Climate models’. So I read with interest the review of climate models included in Chapter 9 of the 5th Assessment report of the state of the Intergovernmental Panel on Climate Change (IPCC) and enjoyed the presentation at the Royal Meteorological Society meeting last week.

I am not a specialist in this field, but I was impressed by the report, by the talk, and by just how good Climate Models are. The report draws on two ‘Coupled Model Inter-comparison Projects’: CMIP Phase 3 which covers 24 models and CMIP Phase 5 which covers 41 models.

Each model makes predictions for one possible evolution of Earth’s weather and its results are then averaged over time and region to yield Climate estimates.

Each model is fed data on the past state of the climate up until (say) 1900 and then calculations are made in roughly 15-minutes steps to see how the climate evolves as the Earth turns, the Sun shines, Volcanoes erupt, and carbon dioxide levels increase.

We then look back at our actual climate records and see how well each model performed. Of particular interest is the average performance of the models – which represents our collective ‘best estimate’ for what will happen.

What struck me most strongly is that the authors highlight where models get things wrong. This is such an unfashionable writing style one could easily get the sense that none of the climate models are ‘correct’. And of course none of them are perfect. But it is this obsession with error and uncertainty which is a hallmark of a community genuinely concerned with accuracy.

Actually, the models do pretty well. For me the most amazing graph was Figure 9.35 on Page 803. It shows the model’s predictions for the variability of the air temperature above the ocean surface in a particular region of the Pacific Ocean. Most models show a pattern of variability with peaks every 2 to 7 years – similar to the observed variability of El Nino events.

But ‘predicting’ the past is relatively easy because ‘bad’ models can be eliminated.

What about predicting the future? Can we say how reliably the models will predict the future? The authors summarise the state of the art thus (Page 745)

In general, there is no direct means of translating quantitative measures of past performance into confident statements about fidelity of future climate projections.

There has been substantial progress since the AR4 [the 4th Assessment Report in 2007] in the methodology to assess the reliability of a multi-model ensemble, and various approaches to improve the precision of multi-model projections are being explored. However, there is still no universal strategy for weighting the projections from different models based on their historical performance.

The models represent our very best attempt to consider all the physical factors of which we are aware, and to work out what is going to happen. Using multiple models and looking at the extent of agreement and disagreement between them is one way of assessing the likely accuracy of the model predictions.

But the long and the short of this is that ‘we just don’t know’ what will happen in the future.

However this shouldn’t diminish the achievements of understanding that these models embody, even if they prove inaccurate in some predictions. Similarly, it would also be unwise to believe them absolutely, even if they prove accurate.

We are talking about the future, and we need to remind ourselves of this. The results of climate forecasts can guide us, and it would be bonkers to ignore their guidance. But the real challenge is to make policy choices now in the face of the real uncertainty.


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