Archive for January, 2010

The carbon footprint of wine

January 31, 2010
Australian-looking man with hat inspecting grapes

Australian-looking man with hat inspecting grapes

If you are one of the dozen or so people that read this blog – yes, you are a select bunch – then let me tell you that many of these blog entries are written after I have imbibed a glass or two of wine. My favourite wines are from the ‘new world’ – Australia and New Zealand – and so I am very personally concerned about the carbon foot print of wines from the New World. And I am in good company.

Looking on the web it is hard to find definitive data. The Winemakers Federation of Australia have a downloadable carbon calculator on their web site which combines comprehensiveness with incomprehensibility. Treehugger quotes some numbers appropriate to the USA that tell a simple story with very profound consequences: transport by road is dramatically worse than transport by boat. For each bottle of wine (weight around 500g of bottle plus 750g of wine):

If you live in New York your options, best to worst, are:

  • Bordeaux, France (which are shipped via ship) = 136 g of CO2 equivalent  (11% of weight)
  • Santiago, Chile (also sent by ship) = 181 g of CO2 equivalent (15% of weight)
  • Sydney, Australia (ship, again) =  409 g of CO2 equivalent (33% of weight)
  • Napa, California (driven by truck) =  2000 g of CO2 equivalent (160% of weight)

And if you live in Los Angeles California:

  • Chilean wines = 227 g of CO2 equivalent (18% of weight)
  • Californian or Australian wines = 272 g of CO2 equivalent (22% of weight)
  • French wines = 1364 g of CO2 equivalent (110% of weight)

So in New York, drinking French wine has a lower carbon footprint that Californian wine, and in Southern California, drinking wine from Chile has a lower carbon footprint that drinking wine from Northern California. These results are at the same time shocking but unsurprising. The implication is that it is not really possible to have a single figure that reflects the carbon footprint of an item of produce, because the carbon emissions associated with transport to its place of consumption are such a significant fraction of its footprint. This insight has not been lost on Tesco who have begun to move wine by canal.

Caveats and implications for the UK

Of course I haven’t verified these figures independently, and I suspect some sources of embodied carbon (such as the glass bottle itself which I estimate amounts to around 75 g of CO2 equivalent) have not been correctly included. But I did once calculate that the CO2 emissions per apple shipped from New Zealand amounted to about 33% of the apple by weight, so the figures for wine seem plausible. The UK is a small island and the high price of fuel has made us distribute goods with relatively high efficiency. I think the same figure of one third to one half of the weight is probably a fair guess for both French and Australian Wines. For American wine it would depend entirely whether it was shipped from the East or West coast. Perhaps I will try a wine box which has a higher weight ratio of wine to packaging…

This article was written with the aid of approximately 350 ml of wine, and 175 g of CO2.

At last! A Rational Lighting Shop

January 31, 2010
Clas Ohlsen LED Light Bulb

Clas Ohlsen LED Light Bulb

While visiting Kingston upon Thames yesterday, I notice a new shop had opened in the premises that used to house Woolworths. I found the shop – Clas Ohlsen – rather hard to classify. It was somewhere between a hardware store, an electrical retailer, a stationer, with a few ‘gadget’ sections. I bought an extremely cheap energy meter (£5.99 on special offer) but it was not until I got home and browsed their catalogue that I realised how much I liked the shop.

On looking at their light bulb section, they had a very clear guide to the different lighting types, and most importantly they stated the number of lumens that each bulb emitted. A lumen is a measure of the amount of light emitted by a bulb as it will be perceived by people. A physical unit which incorporates human perception is rather unusual, but undeniably useful. I had despaired that this information would ever be available on the packaging of light bulbs. It means that I can see that LED light bulbs – now readily available – give out 50 to 70 lumens per watt of electrical power; energy saving light bulbs give out around 40 to 60 lumens per watt; halogen light bulbs give out 12 to 18 lumens per watt and regular incandescent bulbs give about 10 to 12 lumens per watt. NOw I can make rational choices.

Interestingly the guide also gives clear information about when the different classes of light bulb will be phased out; details of dimmable energy saving bulbs and the temperatures at which energy saving bulbs will work – with special bulbs available for outdoor use. Why did it take so long for a shop to simply give people the information they need.

Argon is heavy!

January 30, 2010


Yesterday, I had a curious afternoon weighing a sphere. The sphere in question is a rather perfectly made object manufactured out of two hemispheres so that when they are bolted together the internal surface encloses a highly perfect spherical shape. We are hoping to determine the average internal radius of the sphere by filling it with water and weighing it. However we had severe problems with the water leaking out of gaps through which it should not have leaked. We think we have it sorted now and earlier in the week we tested it with a helium leak tester.

To do this we filled the sphere with helium gas. Helium gas  has light and mobile molecules and they can be guaranteed to find the tiniest of leaks. We then use a ‘sniffer’ outside connected to a mass spectrometer which can very sensitively detect helium exiting the sphere. Actually its all a bit trickier than this – but that is basically what happens. We left the helium in the sphere until just before the weighing when it occurred to me that the helium might affect the weighing, and so I quickly decided to flush it out. However for some reason I chose to flush it out with argon gas rather than compressed air.

After flushing it out for 10 minutes we took the sphere to the rather tasty weighing machine at NWML. As my colleagues set up the balance, they noticed the sphere – which weighs 9 000 g was 300 milligrams (0.3 grams) heavier than the last time weighed it. That may not sound like much – but we need a measurement uncertainty below 0.000 1 grams. After a moment the penny dropped – it was still full of argon. Argon molecules have a relative atomic mass of 40 compared with the average mass of an air molecule of about 28.8. So the 1 litre of argon in the sphere weighed about 1.67 grams rather than 1.2 grams that 1 litre of air would weigh. The difference (0.47 grams or 470 mg) was plenty large enough to explain the observed discrepency if we imagined it also contained a bit of air.

So first I tried using a ‘puffer’ to put air into the sphere, and after re-weighing the mass had fallen by 30 mg. Eventually I had to hold the sphere upside down and shake it in order to empty out the argon while my colleague used the puffer to flush air into the sphere. Eventually we seemed to get rid of most of the argon and the weight of the sphere returned to within a few milligrams of its previous value.

Anyway. I just thought I would mention this because (a) it was a curious moment and (b) it really brought to light very graphically the heaviness of gases in a way in which we are not usually aware – by simply weighing them!

GCSE Physics: The lunatics have taken over the asylum

January 26, 2010
William Hogarth's Bedlam

William Hogarth's Bedlam

On January 18th 2010 I attended a meeting called by QCDA – the Qualifications and Curriculum Development Authority – who were seeking the input of professional physicists into the ongoing revision of the Physics GCSE syllabus. It quickly became clear that QCDA staff thought they knew better than everyone else and they were condescending and contemptuous of anyone else’s opinion. In particular, the head of ‘development’ stated that the problem with GCSE physics ‘was physicists’ and that ‘everyone thinks their subject is hardest:- physics is no harder than religious studies’. I didn’t really know what to do about this experience, and on the same day my cousin died in Ireland, and I had to travel for her funeral. The week was busy and a write-off. However on Satuday I saw an article about ‘worthless exams’ in the Guardian and this re-ignited my desire to do something. I wrote a letter to the paper!

My letter was published today, but my friend Alom Shaha had already posted the letter on a ‘How Should we teach Science‘ web site and I been shocked – overwhelmed indeed – by the extensive support from a wide range of (mainly) teachers. Please read some of these comments. They are shocking and moving. Alom headed this with the phrase I had used to summarise this meeting to my bosses: the lunatics have taken over the asylum.

I really don’t know what to do next. I am busy and this is not my job, but it also doesn’t appear to be anyone’s job to stand up for standards in exams if that means that more people will ‘fail’. QCDA has completely politicised the construction of curricula and will not rest until physics is as easy as religious studies. This matters because many real people – generally we call them children but they are people and they will become citizens – are being disempowered. Why? Because actually physics and engineering remain exactly as hard as they ever were – but the holders of these worthless qualifications will simply not be able to study physics, work in physics, or more widely – bring the benefits of physics insights into whatever career they adopt. Its a tragedy. Its a car crash in slow motion, and it may already be too late.

Men’s participation in higher education

January 16, 2010
Male and Female participation in Higher Education 1969 to 2007

Percentage Male and Female participation in Higher Education 1969 to 2007.

I have commented before on the inequality of the achievements of men and women in our education system. The other day I came across the above data on the now defunct ‘Fat Knowledge‘ blog. It seemed impossible, so I followed links to the US data, and then I tracked down the equivalent UK data. The situation in the UK seems delayed as compared with the US, and the general UK participation rate is lower, but the story looks similar.  The data appear to be bona fide and reflect a systematic decline in the fraction of men who attend higher education.If we accept this as a fact for a moment, let’s have a think about ‘Why?’ and ask whether we should try to do anything.


Well if the figures were reversed I have no doubt that women would cynically remark that it was just another manifestation of men’s institutionalised discrimination against women. So are men entitled to say the same about the situation now? Well I think there are many causes, but I think that men and women are different and that our educational system has indeed become biased in favour of what are typically female learning styles. Its my opinion, and I accept I could be wrong.

What to do?

Well if the figures were reversed I have no doubt that this would be portrayed as a scandal, and it would be asserted that action was urgently required. Well I think the current data are scandalous and I am amazed that every scheme I have come across is about encouraging MORE women to participate in higher education. [These schemes are generally focussed on science and engineering which are portrayed as being especially unwelcoming to women – something which I have to say is simply not true. They are often unwelcoming to EVERYONE – because they are just very difficult! But in general there is no systematic bias against women – quite the opposite]. However I think the problem is very deeply rooted in our educational system. And so I have no prescription for ‘immediate action’ because I just don’t have any faith in educational diktats which change every two or three years. But this is very worrying data, and we will reap the consequences of this in years to come if we allow the situation to persist.

Mobile Phone Safety Talk

January 10, 2010
Banner for Mobile Phone Safety Talk

Banner for Mobile Phone Safety Talk

Just to say that after literally years of negotiations I am finally giving a talk on Mobile Phone Safety under the aegis of the Institute of Engineering and Technology or the IET as they like to call themselves. If they like the talk I will hopefully get the chance to get out and about around the country talking to real people. A real challenge and an opportunity. If you are interested you can register for the talk here: it’s in the evening at King’s College London on the 28th January 2010. Do tell your friends or come along yourself!


January 9, 2010
Michael behind an impossibly bright Birthday Cake

Michael behind an impossibly bright Birthday Cake

I celebrated my 50th birthday a couple of weeks ago, and I have just been sent a photograph – above – of myself next to a cake carrying 50 candles. I don’t normally put much personal stuff on this blog, but the picture just made reflect that there comes a time when simply putting the appropriate number of candles on a cake becomes … just too much! And that’s not to mention the safety implications.

And the picture – imperfect as it is – seemed to perfectly illustrate an idea. The idea being that things which start out being good, when scaled up can become ridiculous. And that is true of so much of the way we live. When one person in 100 has a car, they have great freedom: when everyone has a car we have traffic jams and pollution and carbon dioxide emissions and thousands of deaths each year.

Anyway. On with the year…

Royalty and Science? Let’s break the link.

January 9, 2010

The Royal Society and the Royal Institution are on the ‘A’ list of major world and UK scientific societies. But I would like to suggest that both of them should drop any association with Royalty and change their names.

I have occasionally visited these institutions and – speaking as a ‘grammar school boy’ – they reek of class, privilege, and wealth. I simply wanted to leave the buildings. Now I may be oversensitive in this regard, but I think the effect these institutions have on me – someone who might be generally thought to ‘belong’ in the milieu that would inhabit their hallowed halls – is as nothing to the number of people who would never venture near their doors. It is as true in the 21st century as it was in the 17th, that scientific institutions should in principle and in practice avoid association with ‘establishment’ power. Let’s look at these very different ‘Royal’ establishments in turn.

The Royal Society actually formally uses a byline to explain what it is: The National Academy of Science of the UK and Commonwealth. My comment is that if it needs such a byline, why doesn’t it just call itself what it is? The problems with the organisation’s identity and role are symbolised by the premises it has chosen to occupy.  Carlton House Terrace, overlooking the Mall, with views to Buckingham Palace and Downing Street must be amongst the most expensive locations in the world. It is as legitimate to ask the Royal Society what it is doing in such a location? I have heard senior fellows of the society argue that it gives them access to the people in government who make key decisions. I would argue that a large building in Milton Keynes, Manchester or Bristol and a season ticket to London would achieve the same ends. In a state which is reducing science funding systematically, the Royal Society’s opulence is increasingly anomalous and out of place. And its naming association with Royalty is simply inappropriate for Scientific Society.

The Royal Institution‘s name again gives no clue as to what its aims or activities might involve. It is a charity and does not receive the £45M per year that the Government (i.e. ourselves) gives the Royal Society. It is ‘dedicated to connecting people with the world of science’ and so in modern parlance it is a ‘science centre’ that tries to engage in some real research in a few carefully chosen areas. Once again I fail to see how associations with royalty or a grand location in the poshest part of London helps to achieve that. I find it hard to believe that – Christmas lectures apart – the royal institution has any more impact than, say, the Science Museum or the National Space Centre. Once again, why not call it the National Science Centre and position it somewhere where real people might visit. Perhaps in the Midlands? And if they want to show real scientists at work, why not offer sabbaticals and facilities to the many real scientists who would desperately welcome them, rather trying to build their own small research universe.

Now please let me make clear that this is not a criticism of the people involved in these institutions. They are generally doing their best; often working much harder than me; and are also generally much cleverer than me! They would argue (I imagine) that these are precious historical institutions that we need to preserve and cherish. I disagree. I really feel that its time to turn these institutions upside down and start again. We need institutions built for the future not the past, and very little that was built 200 years ago is still fit for purpose. Its time to move on.

Aircraft and Climate

January 9, 2010
Illustration of how large areas of cirrus cloud are formed from aircraft contrails

Illustration of how large areas of cirrus cloud are formed from aircraft contrails

Ahhh. Summer. I recall last summer looking up at a cloudless sky and seeing aircraft condensation trails – ‘contrails’ – in the sky, and then watching them grow until by late afternoon the whole sky was nearly covered. I reflected that since the radiation imbalance that we believe is leading to climate change is of the order of 0.1% of solar intensity on a sunny day (rough 1 W/m^2 as compared with 1000 W/m^2)  this must be a very significant effect over quite a large region of the Earth.

I have also seen the ‘contrails’ shrink and disappear quickly after the aircraft has passed, and also seen the trail sometime stay quite still in the sky, and at other times develop ‘kinks’. All these different behaviours depend on the temperature and humidity of the atmosphere at these heights (10,000 m – well above the normal ‘weather’ clouds. The jet engines emit water vapour which is hot and quickly cools and condenses to make solid ice crystals (the temperature is around -60 °C). If the atmosphere is supersaturated – i.e. contains moisture looking for a seed on which to condense, these ice crystals can initiate cloud growth. If the atmosphere is undersaturated, then the ice crystals will simply evaporate usually slowly.

The effect on climate is hard to quantify. The high clouds reflect sunlight during the day, but at night will also additionally reflect infra red radiation back to earth, with the exact balance requiring a detailed calculation. That is why I enjoyed seeing a short under documented piece on the BBC web site showing satellite photographs of extremely large areas (more than 10% of the UK land area) of cirrus cloud being formed as a result of contrails from just a couple of aircraft. If we didn’t enjoy the benefits of flying so much, such images would cause us to abandon the practice immediately.

You can read more on this effect here

Wind Energy WOW!

January 9, 2010
Map of Predicted Offshore Wind Farms

Map of Predicted Offshore Wind Farms

What happened?! I was busy despairing that the UK would never get its act together in the field of renewable energy, and all of a sudden I hear announcements of installing 32 GW of generating capacity! Yes. I said 32 GW, or 50% of UK peak electricity demand. Now admittedly this will only generate 10 GW on average (16% of UK peak demand) but there will be times during which the offshore farms are generating close to peak, and in these cases the network could supply over half UK demand.

Please don’t worry: my despair and skepticism have not gone completely – I have kept them in storage for when all these plans and possibilities evaporate. But the grandeur of this engineering vision is exactly on the scale required to meet the challenges we face. I look forward to the day when our ‘smart’ electricity meters alert us to the fact that wind-generated electricity is cheap for the next 6 hours and this would be a good (and cheap) time for us to use our tumble driers. I really hope this all comes to pass.

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