Colloquium on 2021 Nobel Prize in Physics

 Every year the UQ Physics Department has a colloquium where someone describes the science behind the latest Nobel Prize. This year I am going to talk about Parisi and the spin glass problem. My colleague Henry Nourse will talk about the climate modelling part.

In preparation, I have found the book, Spin Glasses and Complexity by Daniel L. Stein and Charles M. Newman, very helpful. It is at the level of a colloquium and has a nice chapter on applications to other areas of science (e.g. proteins, simulated annealing, optimisation, computer science, ...) It enabled me to finally "understand" the background and significance of Hopfield's famous paper from 1982, "Neural networks and physical systems with emergent collective computational abilities".

Thinking about replica symmetry breaking has brought back memories of when I was a graduate student at Princeton. When I started Anderson was thinking about spin glasses a lot and had people working on it. I heard lots of talks about spin glasses, replica symmetry breaking, travelling salesmen, ultrametricity, ... Even David Gross gave a colloquium about work he did on spin glasses, with a very warm introduction by Phil. ["I introduce David Gross the condensed matter theorist"] However, once the cuprates happened at the end of 1986, Anderson seemed to largely drop the spin-glass work. Except for Dan Stein, everyone started working on cuprates. In hindsight, I wonder if that was a mistake. In particular, it might have been better for many of his students if they had worked on complexity rather than cuprates.

Next week I will post a draft of my slides. In the meantime, two questions for readers:

1. What are some specific questions you might like answered in such a colloquium?

2. What are some specific resources you may have come across about this year's prize that you found helpful or interesting?

Here are the slides.

2021 Nobel Prize in Physics: from spin glasses to complexity theory

I was delighted to hear of the award of the Nobel Prize in Physics for 2021. The committee continues to surprise us. I did not make any predictions this year, because I had nothing new to predict. I am still surprised that experimental tests of Bell inequalities (Aspect, Clauser, Zeilinger) have still not got a prize. Maybe next year.

Here I will just write about the award to Giorgio Parisi “for the discovery of the interplay of disorder and fluctuations in physical systems from atomic to planetary scales” as it involves condensed matter theory, beginning with spin glasses, and like many things with Phil Anderson!

The popular science background and the scientific background to the prize are worth reading, as always. It notes that in a Physics Today column Anderson wrote in 1988,

“The history of spin glass may be the best example I know of the dictum that a real scientific mystery is worth pursuing to the ends of the Earth for its own sake, independently of any obvious practical importance or intellectual glamour.” 

This was in the first of a series of seven Reference Frame columns he wrote on spin glasses. The fifth column described the work of Parisi.

Here I will describe the basic ideas, particularly as they show that sometimes obscure basic science questions, very abstract ideas and mathematical formulations can be useful for very practical scientific questions, across a wide range of disciplines.

A spin glass is a distinct state of matter. This means, that in terms of the Landau paradigm, there must be an order parameter and an associated broken symmetry. What are they? Parisi found the answers.

First, as one usually does in theoretical condensed matter, one needs to write down a minimal model Hamiltonian that is complex enough to capture the essential physics but is simple enough to be amenable to analytical and/or computational analysis. 

Sam Edwards and Anderson proposed the following model for a spin glass, and Ising model where the spins are on a regular lattice but the interaction between any pair of spins, J_ik, is a random Gaussian variable with zero mean and non-zero variance.

This means that the interspin interactions are equally likely to be ferromagnetic or antiferromagnetic, leading to significant frustration.

To solve such a model one needs to calculate the partition function Z for each realisation of the J's (disorder), calculate F=- T ln Z, and average over all the configurations of disorder. 

Averaging Z over disorder is just a Gaussian integral, but averaging ln Z is analytically intractable.

Anderson's physical intuition was combined with the mathematical trickery of Edwards, that he had cultivated with his earlier work on quantum field theory and soft matter.

The replica trick is based on an identity that one learns in introductory calculus.

One considers not one system but rather n identical copies (replicas) of the physical system, calculates the average of the partition function for this fictional n-system, and then treats n as a continuous analytical variable and takes the limit that n goes to zero in the formula above. Wow, that is abstract! But, it is tractable.

Personal aside: more than twenty years ago I learned and used the replica trick because (like supersymmetry) as it provides a powerful mathematical tool to treat disorder exactly in one-dimensional models. But, the spin-glass case is much richer and more subtle.

Strange things happen for the spin glass. Soon after Edwards and Anderson's work, Thouless, Anderson, Palmer, and others made the rather puzzling discovery that not all the replicas were the same below the temperature associated with transition to the spin-glass state. The replica symmetry was broken in the spin-glass state.

Parisi proposed the order parameter below for this broken symmetry state. i denotes a lattice site, and the indices alpha and beta denote replicas. When alpha and beta have different values, the order parameter only becomes non-zero when the replicas are different.

Parisi, Toulouse, Mezard, and others then showed that there is a hierarchical structure associated with the order parameter leading to the concept of ultrametricity which can be associated with the rugged energy landscape of not just the spin-glass problem, but also optimisation problems, simulated annealing, protein folding, neural networks, ...

A nice overview that puts the theory of spin glasses in a much broader scientific context is Physics and Complexity by David Sherrington.

On Doug Natelson's blog, nanoscale views, there is a nice discussion in the comments about Parisi's Nobel and the subtle issue of the connections between separation of time scales and ultrametricity, and the connections (or not) between Parisi and climate science.

Sir John Houghton (1931-2020): climate scientist

I was sorry to hear that Sir John Houghton died on April 15, from complications associated with coronavirus. There is a nice obituary in The New York Times.
He was appointed to an array of distinguished and influential positions, including Professor of Physics at Oxford, Director of Rutherford Appleton Lab, Director of the UK Meteorological Office, and most significantly, lead editor of the first three reports of United Nationas Intergovernmental Panel on Climate Change (IPCC).
I highly recommend his autobiography, In the Eye of the Storm, which I blogged about a few years ago, highlighting his integrity and influence.

Crowdsourcing answers to some science questions

Often when I write a post commenter's suggest some useful references. Answers to any of the following questions would be appreciated. The questions relate to things I am curious about, working on or subjects of possible blog posts.

1. Quasi-particles are a key concept in quantum many-body theory. Is there an analogous concept in classical many-body systems, e.g., dense liquids or plasmas?

2. Is there a simple physical argument, possibly accessible to non-experts, of why decreased dimensionality leads to increased fluctuations?
(An example is the Mermin-Wagner theorem). I understand how to mathematically show that fluctuations increase due to decreased phase space, but I am skeptical that I could make this argument comprehensible to a non-expert?

3. Why does increased CO2 in the atmosphere lead to an increased frequency of extreme weather events (cyclones, droughts, floods, ...)? What is the basic physics involved?
This is the scientific aspect of climate change that I understand the least. It also seems to be the aspect of climate change that could be the worst. I write this in the context of the current bushfires in Australia.

4. Who was the first person to write down the Landau theory for a superfluid transition, suggesting that the order parameter was a complex number?
Was it Ginzburg and Pitaevskii in 1958?

5. Who was the first person to fully appreciate that at a critical point the correlation length of the order parameter diverges and fluctuations in the order parameter become large?
[In 1914 Ornstein and Zernike solved this problem for a liquid-gas transition].

6. Are there philosophical problems or paradoxes associated with the principle of least action in quantum mechanics?
Consider a particle that moves from x at time t to x' at time t'. The path taken is that which is an extrema of the action (time integral of the Lagrangian) along that path relative to others. Superficially, that sounds like the particle ''considers" all the possible paths and then "chooses" the right one. Spooky action at a distance? This makes it sound like to understand classical mechanics you have to consider it as a limit of quantum mechanics and just perhaps embrace the many-worlds interpretation....

Post-colonial science

Today there are many threats to science playing an appropriate role in education, public policy, and general public discourse. Some include anti-vaccination campaigns, climate change denial, young earth creationism, "health" products, ...
In the Western world issues such as these rightly get considerable attention. However, in the Majority World there is an issue that does considerable harm and is growing significantly. The basic claims are along the following lines. Modern science did not first arise in Europe but was already present in ancient cultures, often in religious texts. Post-colonial nations need to be proud of this heritage and this "science" should be an integral part of science education. Nations need to embrace their own methods and epistemologies consistent with their culture.

I recently become aware of just how prevalent these views are and the powerful political forces promoting them. You can get some of the flavour from this recent newspaper article and watching some of this video.

A relevant book is
Lost Discoveries: The Ancient Roots of Modern Science—from the Babylonians to the Maya
(Aside: The author, Dick Teresi wrote The God Particle with Leon Lederman.)
This book is authoritatively quoted in a recent book by a prominent South Asian political leader.
A helpful and critical review of Teresi's book is in Science. Basically, it is bad history. There is no doubt that various ancient civilisations did develop some pre-cursors of various aspects of modern mathematics, science, and technology. However, they were never comparable in scope, coherence, conceptual framework, and longevity to what happened in the "scientific revolution" in Europe. A very detailed debunk of some specific claims was given by Meera Nanda, and unfortunately received a vicious response.

So what is the source of the problem here?
I think several very distinct entities get conflated: colonialism, Western civilisation, science, technology, the greed and duplicity of some multinational corporations, and modernism.
A particularly tragic example of this conflation was arguably instrumental in the AIDS-HIV denialism of the South African government from 1999-2008. It was probably responsible for the death of hundreds of thousands of people.

Colonialism was a brutal system which ruthlessly exploited, humiliated, raped, and murdered millions of people across the globe. (See for example). Countless nations today labour under that horrific legacy. No doubt the colonising powers had a patronising view of the "natives", claiming they were bringing them the great achievements of Western civilisation such as science and modernism, and they ruthlessly used technology to maximise their exploitative agenda.
The subtle interplay between scientific, colonial, and theological ideas is described by Sarah Irving in
Natural Science and the Origins of the British Empire.

However, one can decry European colonialism but affirm good things about Western civilisation such as science.
One can decry how technology [based on science] is used to harm people but still affirm science.
Modernism is a particular world view or philosophical framework that claims scientific foundations. One can embrace science without embracing modernism.

I consider postcolonialism an understandable struggle for post-colonial nations to find an identity and direction in the era of globalisation. Somehow these nations need to honor the good parts of their own culture and history [including an accurate assessment of their scientific achievements], accept some good achievements of the West [science, democracy, rule of law, individual freedoms] without uncritically accepting dubious aspects of the West [consumerism, neoliberalism, narcissism, arrogance, ....].

From instrumentation to climate change advocacy

I learned a lot from reading In the Eye of the Storm: The Autobiography of Sir John Houghton (with Gill Tavner). He is arguably best known for being the lead editor of the first three reports of the IPCC (Intergovernmental Panel on Climate Change). He started his scientific life as an atmospheric physicist at Oxford. Here are a few things that struck me.

The value of development of new instruments.
At Oxford Houghton was largely involved in finding new ways to use rocket based instruments measure the temperature and composition of the atmosphere at different heights. These were crucial for getting accurate data that revealed the extent of climate change and understanding climate dynamics. It was good for me to read this. As a theorist, I am often skeptical or at least unappreciative of the value of developing new instruments. I think it is partly because I have heard too many talks about instrument design where it really wasn't clear they were going to generate useful and reliable information, particularly that could be connected to theory.

A reluctant administrator.
I think the best people for senior management are those who don't want the job. The worst are those who desperately want the job. It is interesting to see that Houghton was quite reluctant to leave Oxford when he was asked to be director of Rutherford-Appleton Lab. Then he wanted to go back to Oxford but was persuaded to become head of the Meteorological Office. It is also refreshing to see how he pushed back against some of the "management" nonsense that people wanted to impose on the organisations that he led.

Rigorous peer review at the IPCC.
Just because something is peer reviewed does not mean it is true. However, when there is an overwhelming consensus about some issue in peer-reviewed literature, we can high confidence it is true. Furthermore, at the IPCC there was really a double layer of peer review. The reports were based on reviews of the peer-reviewed literature. Every sentence in the reports was debated and ultimately voted on by a committee of leading scientists with relevant expertise. It is very hard to get scientists to agree on anything. However, when they can agree it means there must be a high probability it is true.

Dirty tactics of denialists.
There are a few stories about the different antics of "observers" at IPCC meetings who worked tirelessly to get IPCC to dilute their reports and sow doubt. Unfortunately, Federick Seitz features along with the lawyer/lobbyist Don Pearlman, who worked for the Global Climate Coalition.

Gracious public engagement.
The book describes how Houghton has worked hard to engage with climate change denialists, particularly among Conservative Christian leaders in the USA.

Finally, the book makes a strong case for concerted action on climate change. The most striking figure in the book was the map of Bangladesh showing how much will go under water, with just a one-metre rise in sea level. As often the case it is the poor that suffer the most.

A changing dimension to public outreach about science

I think it is worth noting that there are many distinct goals for public outreach activities concerning science. These include the following:

Show that science is fun, cool, and beautiful.

Teach about science, both with regard to how it is done and what we know from it.

Recruit students to study science, possibly at a particular institution.

Lobby for increased funding for science.

Enhance the public visibility of a specific institution (lab, university).

Defend scientific knowledge as reliable. 
This is particularly true of areas which have become politicised (partisan) such as climate change, childhood vaccinations, and evolutionary biology, and for which there are significant enterprises promoting "denial", "skepticism", or "alternative" views.

First, given these distinct goals, I think one needs to design activities that are tailored to a specific goal. Previously, I have discussed the problem of doing demonstrations for school kids that actually teach something about science rather than being like a magic show.
Perhaps one can achieve more than one goal, but I think it is unlikely.

Second, what is interesting and of great concern is that the last goal is a relatively new one. There are now sizeable (and sometimes very vocal) sections of the community who think science cannot be trusted. This is well highlighted in a recent Op-Ed piece in the New York Times, A Scientist's March on Washington is a Bad Idea by Robert S. Young. I agree with his argument that given the nature of the problem a march may be counter-productive, particularly as it will be painted as just another "liberal" political lobby group. A better strategy is for scientists to engage with a diverse range of community groups at a more grass roots level. Sometimes this means using subtle and diplomatic strategies such as described in this NYT article and by Katharine Hayhoe.

Third, this problem is very challenging because it is part of a much larger political and social problem, particularly in the USA. There is now a significant fraction of the population who have become disenfranchised from and distrustful of a broad range of public institutions: government, multi-national companies, universities, mainstream media, Wall street, "elites", ..... and science gets lumped in with all that.

Postscript (April 25).
The Marches for Science have now happened around the world. There are broader concerns, beyond those raised by the NYT article, that are eloquently presented by Vinoth Ramachandra.

Clouds, climate change, and emergence

On tuesday the Telluride Science Research Center hosted a nice public lecture, "Clouds in a bowl of soup," by Graham Feingold, an atmospheric scientist.

He emphasised how the atmosphere is a complex system that exhibits emergent phenomena, particularly pattern formation and synchronisation. He discussed how one sees these phenomena in other systems, such as soup (Rayleigh-Benard convection cells) and fire flies.
Aside: in a similar vein there is a nice Physics Today, Quick Study, The universe in a cup of coffee by John Wettlaufer.

Emergent behaviour results from simple rules. The four rules for clouds are

1. Drops form on aerosols (suspended particles) and grow by vapour diffusion.

2. Drop coalescence generates rain. (Aerosols can influence rain).

3. Drops fall and evaporate.

4. Continuity of air flow.

Some of the work he described is in this paper, which includes the figure below.

Some key physics relevant to climate change is that clouds generally reflect sunlight and have a cooling effect. The big question is whether global warming then increases or decreases cloud formation. Is the feedback positive or negative? It seems people aren't really sure. Intuitively, you might think that the increased water in the atmosphere means more clouds but (as is often the case) it turns out to be more complicated than that.

A career transition from theoretical physics to public policy

Robert Socolow has an interesting career history. He started out in elementary particle theory, with a Ph.D at Harvard, a postdoc at Berkeley and was an Assistant Professor at Yale. He then made a transition to environmental and energy policy, joining the faculty in Mechanical and Aerospace Engineering at Princeton in 1971. There is an interesting letter he wrote to Steve Fels in 1969 that describes his transition in research interests.

Two years ago Socolow gave a Homage to Frank von Hippel, a physicist who made a similar transition, focusing on nuclear policy and arms control. It is worth reading. Here are some comments Socolow made about physics.

Physics is a special way of knowing, within science. Physics stresses simplification – incredibly useful when other fields place a much lower value on simplification. The physics approach shines a light on other sciences, provides accessibility for outsiders (the intelligent layman).  

Although our cohort stopped working at the frontier of physics, arguably we didn’t leave physics but rather we enlarged the scope of physics. APS has remained our institutional home. A whole cohort of us moved from frontier physics into fields that did not exist beforehand -- fields that did not construct entry points until a long time afterwards. In the 1970s our cohort had a role in creating APS institutions like the Panel on Public Affairs (POPA), the Forum on Physics and Society, and the APS Fellows Program. Frank and I were two of the first six APS Fellows whose route to Fellow was via the Forum on Physics and Society. 

Less than a week ago I was at Harvard for a reunion of all those who received Ph.D.’s in Physics from Harvard, as well as faculty from all periods and current graduate students. There were two morning panels on alternative careers for physicists, featuring alumni now doing different things. Sadly, in my view, nearly all of the panelists had moved from physics to finance. I invited myself onto one panel, and Dan Kammen was on the other one. We reminded the audience that critically important problems were out there which physicists could contribute to. Our message seemed not especially welcome.

I do think physicists have a lot to contribute. Socolow and von Hippel are great role models. However, I also think we have to be careful about "physics hubris", most commonly manifested in two related directions. The first is being naive about how complex problems are. Second, being arrogant and thinking that we are smarter than others who have already spent a lot of time working on these problems. Previously, I wrote about How (not) to break into a new field.

Is this the ultimate compliment for your paper?

For someone to put the main points to a popular song!

Yesterday I heard an interesting talk "Truths we must tell ourselves if we are to manage climate change" at UQ by Robert Socolow [aged 80!].

He is well known for a paper, Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies

The paper considers Seven ways to reduce carbon emissions. Glenn Wolkenfeld has written corresponding lyrics to the tune of the classic Paul Simon song, 50 ways to leave your lover!



Socolow has an interesting career history, having started out in theoretical physics, working on elementary particles. I will write more about that career transition later.

Infrared spectroscopy: What is the Condon approximation?

How do you calculate the absorption intensity associated with a molecular vibration?
First, why might you care?
This is not just a basic scientific issue that is only of interest to people working in molecular spectroscopy.
It actually lies at the heart of global warming. For example, why is methane a much worse greenhouse gas than carbon dioxide? It is because it has a much larger infrared (IR) absorption intensity in the relevant frequency range.

In the electronic ground state consider a transition from a vibrational level with quantum number j to one with i. The absorption intensity is given by

where the dipole matrix element between the two vibrational states is

I  use r to denote all the nuclear co-ordinates.

mu_g (r)  is the dipole moment of the molecule in the electronic ground state.

For notational simplicity I neglect the vector character of the dipole moment.

One can now make an approximation to greatly simplify evaluation of this matrix element and to provide some physical insight. One approximates the dipole moment by its first derivative term in a Taylor expansion.

This is known as the Condon approximation.

Aside: I can't find the original reference. Please let know if you know it.

This is a very useful approximation. First, it give some insight.

a.
It tells us that the IR intensity is dominated by the variation in the dipole moment of the electronic ground state with nuclear co-ordinates.

b.
If the nuclear wave functions are harmonic, then the only non-zero IR transition is that of the fundamental (i.e. from the ground state i=0 to the first vibrational excited state, i=1). There are no overtones, i.e. higher harmonics. This is known as the double harmonic approximation. (The first is the Condon approximation).
In reality, all potential energy surfaces are slightly anharmonic and so this leads to the presence of weak overtones in IR spectra. Their intensity can be used to estimate the amount of anharmonicity, both in the potential and the dipole moment surface (i.e. deviations from Condon).

Second, the Condon approximation makes calculations of intensities a lot easier. One does not need to calculate the full dipole surface, mu_g(r) just its first derivative at the equilibrium geometry. This is what almost all computational quantum chemistry codes do.

How reliable is the Condon approximation?
It seems to be very good for most molecules. Corrections are often only a few percent.
Here is one study by Juana Vazquez and John Stanton.
One can measure vibrational frequencies extremely accurately (especially in the gas phase), e.g. to within 0.01 per cent. In contrast, one can usually only measure vibrational intensities to within about 10 per cent. This provides less motivation to worry about corrections to Condon.

However, there are exceptions. Jim Skinner and collaborators have shown how for the OH stretch in liquid water one needs to take into account the dependence of the dipole moment on the nuclear co-ordinates of the surrounding water molecules.

Will burning lots of coal lift people out of poverty?

A few months ago I attended a symposium at UQ on Energy in India. The talks can be viewed on Youtube. The one by Alexie Seller is particularly inspiring.

In the presentation of Chris Greig he showed a slide similar to that below with the title "Electricity affects Human well being".

He did not say it, but sometimes graphs like this are used to make claims such as "the more electricity people consume the better off they will be..."  or "the only way to lift people out of poverty is to burn more coal..."

Sometimes people show graphs that correlate GDP with energy consumption. But this one is better because it uses the Human Development Index, a multi-dimensional measure of human well being (as it includes life expectancy and education).

Two things are very striking about the graph.
First, the initial slope is very large. Second, the graph levels off quickly.
A little bit of electricity makes a huge difference. If you don't have electric lighting or minimal electricity to run hospitals, schools, basic communications, water pumps and treatment plants, ... then life is going to be difficult.
However, once you get to about 2000 kW hours per person per year, all the extra electricity beyond that makes little difference to basic human well being. This is frivolous use of air conditioners, aluminium smelters, conspicuous consumption, ...

Finally, we always need to distinguish correlation and causality. As people become more prosperous they do tend to consume more electricity. However, it is not necessarily the electricity consumption that is making them more prosperous. This is clearly seen by how flat the top of the curve is. Electricity consumption in Canada is almost four times that of Spain!

A more detailed discussion of the graph is in this book chapter by Vaclav Smil.

A student's questions about scientists responding to climate change

A first year undergraduate student who is deeply concerned about climate change asked me a number of questions by email and then came to my office to discuss them. Since I think they are excellent questions I thought I would post them here (with his permission) and give a brief version of my answers. I welcome readers to give their own answers.

I am interested in and passionate about climate change. At the moment, I'm considering my uni options - wondering what I can study to best equip me to help in the great, global effort to mitigate (I'm a bit less interested in adaptation) climate change. I have a couple of questions to ask of you.

1. How would you respond to each of the following, somewhat contradictory statements: 

- 'Climate change can be mitigated by developing and deploying renewable energy and energy efficiency technologies, without significantly impacting on our standard of living.' 

- 'Environmental crises, including climate change, require us to move away from a social and economic system based on consumerism and growth' .

First, I am no expert on this complex issue. An economist at UQ who is an expert is John Quiggin. But, my view is that with energy efficiency measures, renewable energy, and some modest lifestyle changes significant progress can be made towards mitigating climate change. On the other hand, I think there are compelling social  and political reasons why the world, particularly the Western world, would be better off if we moved away from this mindless and insatiable pursuit of consumerism and economic growth.

But, I really think the biggest obstacle to concerted and significant global action is a lack of political will and leadership. This is particularly driven by "fear mongering" from vested business and political interests who claim the first option is true. "If we don't burn more coal we will all end up back in the caves or at least riding bicycles..."
I don't think the biggest obstacle is missing technical and economic solutions. Of course, if someone can make a durable and reliable photovoltaic cell with 20 per cent efficiency, that costs 20 cents per square metre to manufacture, and with a lifetime of 20 years, it would "solve" the problem. But, I only foresee incremental advances in the next decade. The case of Gratzel cells is quite discouraging.

2. If the institutional ethos of the UQ science faculty were a person, how would he/she respond to the above statements? 

I think you would really encounter a range of views, probably reflecting a rang of political convictions. I would hope most staff would believe that climate change is real, a result of human activity, and a major issue to address. On the other hand, I am occasionally surprised and disappointed to meet scientists, who are skeptics, even though 97 per cent of climate scientists are not.

I think you would find that some would also claim we need lots more research money (especially for new technologies) to address these issues, but they are clouded by self interest.

3. What facets of science would you recommend that I study:  

- Earth science (better understanding of the climate system)

- Physics/Engineering (renewable energy technology) 

- Psychology (Why do people behave the way they do) 

- Ecology (how ecosystems respond to climate change and other pressures)

Given that I think the major obstacles are political I think that becoming a political activist you may have the biggest impact. Studying sociology and psychology may help design the most effective campaigns. But you do need to understand the technical issues.
On the other hand, you should consider what you are good at and enjoy. There is no point trying to put square pegs in round holes.
Hence, I think you should let your own interests and abilities be a consideration. But studying a mix of the above could be very helpful.

I am wondering if UQ has plans to develop a specific course, or even a program, devoted to climate change?

Not that I am aware of. There are significant postgraduate activities at The Global Change Institute and the Energy Initiative. There was recently a review of the Bachelor of Science. The possibility of some elective courses that are multi-disciplinary has been floated and climate change is one. However, my experience is that such courses become a can of worms once you get multiple departments involved. Everyone wants a piece of the pie, to do it their way, but are not willing to take responsibility, or to "force" their own students to take the course so it is viable. Hence, I doubt you will see the kind of course you are hoping for during your time here. Sorry.

We ended our discussion with me lending the student a copy of The Eye of the Storm: the autobiography of Sir John Houghton. He is nice example of someone who moved from basic research in climate science to public policy and advocacy.

I wish I had more discussions like this with students.

I welcome people to give their own answers.

Climate change action at the grass roots

When I was recently visiting my mother-in-law in Anacortes, Washington she took my wife and I to a meeting of the local chapter of Transition, an international grass roots movement responding to climate change.
First, an employee of a local not-for-profit Sustainable Connections spoke briefly about home energy efficiency audits that they organise.
Then there was an interesting talk from a local climate change researcher, Roger Fuller, that focussed on the potential impact of climate change on surrounding Skagit County. It is somewhat unique because much the water flowing through the county comes from glacial snow melt in the nearby Cascade mountains. Increased temperatures will mean a greater rain/snow ratio, and greater river flow in the winter and less in the spring. This could have significant effects on the frequency of extreme flooding events.

I think these local initiatives are particularly important beyond the immediate concrete [but modest] energy savings and reduced CO2 emissions that they produce. Such initiatives provide models for wider more ambitious programs and show politicians and policy makers that some people are concerned about climate change and willing to make life style changes.

Besides the significant benefit of addressing climate change this initiative has the other benefit of building community in the face of rapidly declining social capital.

I also picked up a copy of the excellent free booklet Climate Change: Evidence, Impacts, and Choices, produced by the National Research Council for the general public.

Anacortes is one of 50 communities [with a population between 5,000 and 250,000] in the USA that are competing for the $5 million Georgetown University Energy Prize. Each community tries to cut its energy consumption by as much as possible in 2015.

The challenging interface of science, policy, and politics

Last week I went to an interesting talk What are the effects of dredging on the Great Barrier Reef?

by Laurence McCook, at the Global Change Institute at UQ.

I went because I knew Laurence in my undergraduate days at ANU. In first year we had all the same lectures, tutorials, and labs. (I guess groups were assigned based on the alphabet.) We became friends and he introduced me to many beautiful places for bushwalking [backpacking] and cross country skiing near Canberra.

There is a piece on the Conversation that gives a brief summary of the issues associated with the report from the expert panel that Laurence and  Britta Schaffelke co-chaired. Basically, it involved a "cat herding" exercise with 17 experts from industry, government, and universities. I am always impressed by people who manage such enterprises and can produce concrete useful outcomes. I think it requires considerable patience, political skills, and leadership. 

A helpful figure is below.

Aside: it would be interesting to try and do an exercise like this for topics such as cuprate superconductors, topological quantum computing, water, glasses, quantum molecular biophysics......

So what effect does dredging have?

Specifically, which of the effects is most likely to do the greatest environmental damage?

It seems that the ongoing turbidity [cloudy water] and sedimentation associated with sediment dynamics could be the biggest problem. But, this is also one of the most poorly understood processes. 

The figure below summarises some of the complex processes involved. Modelling this presents a major challenge (and some interesting science).

A problem with these exercises where science meets policy meets politics, particularly on controversial issues, is that they can highlight uncertainty and the general public does not like that. Science is meant to be certain. People want black and white answers. "Dredging is harmless and we should not worry about it vs. Dredging is an environmental disaster and should be banned".

It is interesting that of "10 scientific ideas that scientists wish you would stop mis-using" the first is Proof.

The cheapest and cleanest energy source is efficiency

The Economist has a good editorial
Seize the day
The fall in the price of oil and gas provides a once-in-a-generation opportunity to fix bad energy policies

Governments need to do two main things.
First, cut fuel subsidies. This is particularly important in the Majority world, as this favours the wealthy, who can afford to drive cars. Indonesia has just done this and used the saves to fund education and welfare.
Second, cut subsidies that encourage oil and gas exploration and production, rather than renewables.

There is also a 10 page special report
Let there be light 
Thanks to better technology and improved efficiency, energy is becoming cleaner and more plentiful

The two most striking graphs are those below.

A realistic debate about climate change in the media

One of the many problems of the news media is that they love conflict and controversy. So much so, that they will not just amplify it and feed it, but even create it. This certainly happens with the issue of climate change. This video nicely illustrates the point with humour.

 

Public accountability gone amok?

Physics Today has a fascinating review by Naomi Oreskes of the book The Hockey Stick and the Climate Wars by Michael Mann.
In the Print edition the review is entitled, "A call to throw caution to the wind".
I suggest reading the one page review in full with two questions in mind:

1.
How would you personally cope with the level of public scrutiny (and attack) that Mann was subjected to following publication of his 1998 Nature paper?
e.g., having emails and grant applications subject to subpoenas from politicians. The Wikipedia page on Mann describes the many investigations he has been subjected to.

2.
Is it really possible for non-scientists to understand and realistically evaluate the evidence for and against scientific hypotheses concerning complex systems?
Oreskes seems to claim not in this political context and suggests Mann should not have been so cautious with his public pronouncements about ambiguities and subtleties in the data.

If people post their answers to one or both of these questions I will then will try and give mine.

Students need to walk before they can run

There is an interesting Editorial in the Journal of Chemical Education
Science Education for Global Sustainability: What Is Necessary for Teaching, Learning, and Assessment Strategies?
by Uri Zoller.

I agree with many of his concerns and sentiments. Clearly he has thought about the relevant issues and worked hard at trying to implement them. I particularly like the sample exam questions he uses to illustrate his goals.

However, I feel that some of his proposed solutions are unrealistic (e.g., no text books) and unhelpful to students, particularly for beginning undergraduates. I think (and my anecdotal observations are) that multi-disciplinary courses are either too hard (or too superficial) for such students. Students need to learn basic chemistry, physics, and biology before they can  cope with integrating these ideas in biophysics, materials science, or environmental policy.

I thank Ross Jansen-van Vuuren for bringing the article to my attention.

Quantum effects, hydrogen bonds, and climate change

At the workshop today Tom Markland gave a nice talk on work described in a recent PNAS paper Unraveling quantum effects in water using isotopic fractionation.

It turns out that the amount of deuterium in liquid water depends on the temperature at which the water was condensed. This can be measured very accurately and has proven to be a sensitive probe in climate change studies (see for example, figure 1 in this Nature paper).

For most temperatures there is a preference for HOD to reside in the liquid rather than the vapour phase. This is a purely quantum effect! According to the Born-Oppenheimer approximation the intermolecular and intramolecular interaction potentials for H2O and HOD are identical. However, different isotopic masses lead to different vibrational frequencies, zero point energies, and free energies.

Calculating the free energy of the liquid phase where one treats the H and D atoms fully quantum mechanically is a highly non-trivial exercise. Markland has done this using a path integral method based on mapping quantum dynamics to fictitious polymer beads.

The vertical scale is 1000 times the difference between the HOD and H2O free energy difference between liquid and vapour, divided by k_B T.

A few notes:

• Different models for the water interactions give quite different results. It seems including the anharmonic part of the OH stretch potential is important.

• This is an extremely small effect. The differences in free energies are less than k_B T/10 ~ 3 meV at T=300 K. Hence, it is impressive that one can calculate it successfully (provided one has the "right" potential).

• The effect gets smaller with increasing temperature because the density of the liquid phase (along the liquid-vapour co-existence line) decreases with increasing temperature and vanishes at the critical temperature (around 650 K). For example, between 300 and 600 K the density of the liquid decreases by a factor of 1.5. This corresponds to an increase of the average oxygen atom separation from 3.0 to 3.4 Angstroms. I would estimate this corresponds to an eight-fold decrease in the hydrogen bonding energy. There will be an associated significant change in the intermolecular potential, it becoming much more like that in the vapour phase.