What is Climate Change?

21 October, 2013

Here are the slides for a 15-minute talk I’m giving on Friday for the Interdisciplinary Climate Change Workshop at the Balsillie School of International Affairs:

What is Climate Change?

This will be the first talk of the workshop. Many participants are focused on diplomacy and economics. None are officially biologists or ecologists. So, I want to set the stage with a broad perspective that fits humans into the biosphere as a whole.

I claim that climate change is just one aspect of something bigger: a new geological epoch, the Anthropocene.

I start with evidence that human civilization is having such a big impact on the biosphere that we’re entering a new geological epoch.

Then I point out what this implies. Climate change is not an isolated ‘problem’ of the sort routinely ‘solved’ by existing human institutions. It is part of a shift from the exponential growth phase of human impact on the biosphere to a new, uncharted phase.

In this new phase, institutions and attitudes will change dramatically, like it or not:

Before we could treat ‘nature’ as distinct from ‘civilization’. Now, there is no nature separate from civilization.

Before, we might imagine ‘economic growth’ an almost unalloyed good, with many externalities disregarded. Now, many forms of growth have reached the point where they push the biosphere toward tipping points.

In a separate talk I’ll say a bit about ‘what we can do about it’. So, nothing about that here. You can click on words in blue to see sources for the information.

The EU’s Biggest Renewable Energy Source

18 September, 2013

Puzzle. The European Union has a goal of producing 20% of all its energy from renewable sources by 2020. Right now, which source of renewable energy does the EU use most?

1) wind
2) solar
3) hydropower
4) tides
5) geothermal
6) trash
7) wood
8) bureaucrats in hamster wheels
9) trolls

Think about it a bit before reading further!

The Economist writes:

Which source of renewable energy is most important to the European Union? Solar power, perhaps? (Europe has three-quarters of the world’s total installed capacity of solar photovoltaic energy.) Or wind? (Germany trebled its wind-power capacity in the past decade.) The answer is neither. By far the largest so-called renewable fuel used in Europe is wood.

In its various forms, from sticks to pellets to sawdust, wood (or to use its fashionable name, biomass) accounts for about half of Europe’s renewable-energy consumption. In some countries, such as Poland and Finland, wood meets more than 80% of renewable-energy demand. Even in Germany, home of the Energiewende (energy transformation) which has poured huge subsidies into wind and solar power, 38% of non-fossil fuel consumption comes from the stuff.

I haven’t yet found confirmation of this on the EU’s own websites, but this page:

• Eurostat, Renewable energy statistics.

says that in 2010, 67.6% of primary renewable energy production in the EU came from “biomass and waste”. This is at least compatible with The Economist‘s claims. Hydropower accounted for 18.9%, wind for 7.7%, geothermal for 3.5% and solar for just 2.2%.

It seems that because wood counts as renewable energy in the EU, and there are big incentives to increase the use of renewable energy, demand for wood is booming. According to the Economist, imports of wood pellets into the EU rose by 50% in 2010 alone. They say that thanks to Chinese as well as EU demand, global trade in these pellets could rise five- or sixfold from 10-12 million tonnes a year now to 60 million tonnes by 2020.

Wood from tree farms may be approximately carbon-neutral, but turning it into pellets takes energy… and importing wood pellets takes more. The EU may be making a mistake here.

Or maybe not.

Either way, it’s interesting that we always hear about the rising use of wind and solar in the EU, but not about wood.

Can you find more statistics or well-informed discussions about wood as a renewable energy source?

Here’s the article:

Wood: the fuel of the future, The Economist, 6 April 2013.

If its facts are wrong, I’d like to know.

P.S. – This is the 400th post on this blog!

Localizing and Networking Basic Technology

8 May, 2013

guest post by Iuval Clejan

Natural philosophy (aka science) is distinguished from pure philosophy or mathematics by coupling theory to experiment. Engineering is distinguished from science in its focus on solving practical problems rather than merely coming up with more accurate models of the universe. Climate change will not be fixed by pure philosophy or argumentation. We need to use the methods of science and engineering to make progress towards a solution. The problem is complicated and involves not just climate dynamics and ecology, but psychology, economics and technology. Besides theory and experiment, we now have the tool of simulation. I propose a think-tank (or more properly, a think/do/simulate-tank) analogous to the Manhattan Project, which developed the first atomic bomb. However, this project would involve social and physical scientists, computer programmers, engineers, farmers and craftspeople who are trying to collaboratively solve the problem of how to provide food, shelter, water, clothes, medicine and recreation for a self contained village in a sustainable way. Sustainability has psychological dimensions, not just ecological. For example, it implies that people would want to keep living in this village, or similar villages. If we are interested in sustainability beyond the initial village, then sustainability implies replicability—that the village would inspire many other people to live similarly.

Initial outputs of this project would be well-founded suggestions regarding what kinds of production skills are needed and how to effectively network them, how many people, how much land, how much time spent on production in order to achieve village-scale independence and sustainability. An eventual outcome would be an actual demonstration of a functional village.

Why village? The word village is used here to mean a group of people who are economically networked in isolation from the rest of the global economy. It also implies choosing a particular geographic location, so not all outputs would be transferable to other locations, though with the initial simulation stage many locations could be tried.

Why economic isolation? Without putting a boundary on the experiment, the problem is too complex, even for simulation. Entropy reduction is the same reason cells have membranes and scientists have labs. The membrane could be permeable to sunlight, wind (and emissions) and water, but at first it might be simpler to keep it impermeable to economic exchange. In addition, it is easy to externalize all unsustainable practices without a membrane. But the size of the membrane is not predetermined. One possible conclusion might be that the village has to be the size of the whole earth. Another reason for starting with a village is that changes in biological (and probably other complex) systems always proceed from small populations that can spread out by replication. It is more practical to achieve a global change in lifestyle and technology starting with a small group of willing people who can then inspire others by example, rather than try to impose a change on a large population, the way fascist and communist experiments have proceeded. Another reason for keeping things smaller and more local is that a stronger feedback between production and consumption may arise, which would regulate unsustainable consumption, because the environmental, social and psychological costs of production are visible in the village, as opposed to hidden or abstracted from the consumers. There are other reasons for localization (e.g. resilience, freedom, more meaningful employment for more people, better relations among people or between people and nature), less directly related to climate change, and more speculative.

This is probably the place to admit my main bias. I am a Gandhist Luddite (who has a PhD in Physics, worked as a semiconductor engineer and a molecular biologist) , not the angry, machine-smashing kind, and I like not only to tinker with technology, but to think how it affects people and nature. I don’t think all technology can be equated with progress. I call this project the Luddite Manhattan Project (or or Localizing and Networking Basic Technology project) for that reason and because it parallels the project that produced the nuclear bomb. I think that the craftspeople and farmers would contribute more to this project than the scientists and engineers. I think that in the multidimensional optimization of technology, we have focused too much on efficiency (disregarding other human values) and that the industrial revolution was largely a mistake (though some good things came out of it, like global communication). If we focus on other human values, we can optimize technology better. I think that localism of basic-needs production (when coupled to non-technological things like democracy) is a constraint from which many other good things such as sustainability, full, meaningful employment, freedom, and good social relations would follow, though it too can be taken to extremes. Given my bias, I suspect that the kind of technology network that would be most sustainable would be pre-industrial, with a few modern innovations. If we really did the book-keeping accurately we would probably find that industrial production is unsustainable. Or rather we would find that pre-industrial production can be sustainable, while current industrial production is not (I leave open the possibility that industrial production might be sustainable in the future, with new innovations, but even then it tramples too many human values). But these conclusions would be outputs of the project, not pre-assumptions or inputs of the project. I welcome some discussion of these ideas, followed by computation, testing and implementation.

The technical part of the project is basically a networking problem. It would allow initial imports (in a way that would allow replicability—that is don’t hog a disproportionate fraction of resources into the village) into a specific location and then network existing technologies so that the system is self-sustaining. What one craftsperson produces, others in the village must use so that the village can continue in perpetuity. A blacksmith needs some fuel, but also customers who need his products and can exchange stuff that he needs. A cooper is mostly useless in the current industrial economy, but would probably find some use in a local village economy, where people need ways to store water and other liquids.

Here are some typical challenges and questions the project would face: How can antibiotics be made on a village scale with no external inputs? What can’t be made and can we find substitutes? Are there missing technology links and can we invent them, or do we need to start with another scenario? What food needs to be produced to provide basic caloric needs to all inhabitants of the village? How much area is required? How can water be captured and transported without plastic or rubber? How much carbon is emitted in production of everything? Where does garbage go? How can metals be recycled? Can plastic be produced? Can electronics be produced? Is there enough time for art, science, scholarship and other forms of edifying human activity? What kind of economic systems work? Is there an optimal one as far as sustainability, or is it a matter of personal preference? These are all questions that can be tackled, if we face them with curiosity and realism, instead of with fear and the kind of magical thinking that most people have towards technology and other things they don’t understand. I’ve heard that Leonardo Da Vinci was the last man to understand the technology of his age, but we have computers to help us.

It might be appropriate at this stage to mention that I do not advocate giving up entirely the industrial mode of production, or the global trade it requires. The Localizing and Networking Basic Technology project would address only food, shelter, water, medicine, all the subsidiary crafts necessary to sustain these, and a few edifying human activities like art, music and scholarship. Computers and internet hardware are almost certainly best left to industrial production, and so are cars, airplanes (but the need for these will drastically decrease if this project is successful), some of the parts for particle accelerators and fancy biotech equipment, etc.

The initial computational stage of the project could model itself on online multiplayer games like Warcraft and planning games like Sim City (I have tried to contact Will Wright, to no avail). I do not play these games (I prefer simple low tech games personally), but I see the usefulness of online collaboration and computation for this project, as a sort of in-silico evolution. Programmers and mathematicians could set up the software to allow both online collaboration and some central planning. I think the simplest solutions should be tried first, i.e. the most primitive technologies, like hunting and gathering. My educated guess is that they will be shown incapable of providing basic needs given the current world population. The same conclusion would probably follow for current industrial production, except the incapacity would be with regards to sustainability. I predict the sweet spot where both sustainability and capacity to “feed the world” (meaning provide a decent life) would be achieved by pre-industrial, agrarian and craft-based production.

I am totally willing to be proven wrong by this experiment about my anti-industrialization bias. With regards to scientific experimentation, there needs to be well posed hypotheses that can be proven wrong, and good controls. The engineering approach is an alternative. Who is willing to work on this project? Let’s make amends for unleashing the horror of the Bomb on the earth, tackle climate change realistically and have some technical fun. For further information please see:

• Iuval Clejan, Luddite Manhattan Project, first stage, 16 April 2012.

• Iuval Clejan, A proposal for funding a blueprint of a village-based technology ecosystem, 5 February 2012.

Energy and the Environment – What Physicists Can Do

25 April, 2013


The Perimeter Institute is a futuristic-looking place where over 250 physicists are thinking about quantum gravity, quantum information theory, cosmology and the like. Since I work on some of these things, I was recently invited to give the weekly colloquium there. But I took the opportunity to try to rally them into action:

Energy and the Environment: What Physicists Can Do. Watch the video or read the slides.

Abstract. The global warming crisis is part of a bigger transformation in which humanity realizes that the Earth is a finite system and that our population, energy usage, and the like cannot continue to grow exponentially. While politics and economics pose the biggest challenges, physicists are in a good position to help make this transition a bit easier. After a quick review of the problems, we discuss a few ways physicists can help.

On the video you can hear me say a lot of stuff that’s not on the slides: it’s more of a coherent story. The advantage of the slides is that anything in blue, you can click on to get more information. So for example, when I say that solar power capacity has been growing annually by 75% in recent years, you can see where I got that number.

I was pleased by the response to this talk. Naturally, it was not a case of physicists saying “okay, tomorrow I’ll quit working on the foundations of quantum mechanics and start trying to improve quantum dot solar cells.” It’s more about getting them to see that huge problems are looming ahead of us… and to see the huge opportunities for physicists who are willing to face these problems head-on, starting now. Work on energy technologies, the smart grid, and ‘ecotechnology’ is going to keep growing. I think a bunch of the younger folks, at least, could see this.

However, perhaps the best immediate outcome of this talk was that Lee Smolin introduced me to Manjana Milkoreit. She’s at the school of international affairs at Waterloo University, practically next door to the Perimeter Institute. She works on “climate change governance, cognition and belief systems, international security, complex systems approaches, especially threshold behavior, and the science-policy interface.”

So, she knows a lot about the all-important human and political side of climate change. Right now she’s interviewing diplomats involved in climate treaty negotiations, trying to see what they believe about climate change. And it’s very interesting!

In my next post, I’ll talk about something she pointed me to. Namely: what we can do to hold the temperature increase to 2 °C or less, given that the pledges made by various nations aren’t enough.

Mathematics for Sustainability (Part 2)

21 November, 2012

guest post by John Roe

• Michael Blastland and Andrew Dilnot, Commonsense Guide to Understanding Numbers in the News, in Politics, and in Life, Gotham, New York, 2008. (Review at New York Times.)

In Mathematics for Sustainability 1 I explained that I want to develop a new Gen Ed course “to enable students to develop the quantitative and qualitative skills needed to reason effectively about environmental and economic sustainability”. With this as the general objective, what are some of the specific content areas that the course should address, and what should be the specific objectives within each content area?

Right now, I see four mathematical content areas:

• Measuring
• Changing
• Networking
• Risking

Measuring – using numbers (including “large” and “small” numbers) to get an idea of the size and significance of things. Including, for instance: physical units, prefixes (mega, giga, nano, and all that), percentages/ratios, estimation, reliability. That’s a list of concepts on the math side but of course the examples should be sustainability focused. So I’d like the students to be able to answer questions like

• An inch of rain falls over a forest plot of an area 3.21 square miles. How many tons of water fall?

• Roughly, what is the total mass of carbon dioxide in the
Earth’s atmosphere at present?

• Suppose that a nuclear accident spreads 2.3 grams of cesium-137 uniformly over an area of 900 square miles. Compare the radioactivity from this source with the natural background.

• On average, how many gallons of gasoline per second are burned on the Pennsylvania Turnpike?

• A 10-acre farm near State College can produce enough food to support how many people on a vegetarian diet? On a “standard American” diet?

• Roughly, how many birds do you think there are in the world? How accurate do you think your estimate is?

Of course, part of “being able to answer” such questions is being able to know what additional questions to ask in order to give reasonable answers.

I am looking at several books in order to get a handle on this part of the course. Right now I am reading The Numbers Game by Blastland and Dilnot. It starts with an arresting example: how many centenarians are there in the US? That should be easy: just count, right? In fact, census returns ask people to report their age. But the self-reported numbers vary wildly and are estimated to be exaggerated by factors of 20 or more in some cases. Starting from this example, the book seems to give a good overview both of the difficulty and the importance of measuring, both in absolute and relative terms.

Any more suggestions for this part? Thanks!

I am thinking now to put the important distinction between stocks and flows in this section too. (We have to know what we are measuring!) Logically, it might belong in the Changing section but pedagogically it seems better here. A reader on Azimuth sent me a link to this interesting paper which points out how important the stock/flow distinction is in public (mis)understanding of the greenhouse effect:

• John D. Sterman and Linda Booth Sweeney, Understanding public complacency about climate change: adults’ mental models of climate change violate conservation of matter, Climatic Change 80 (2007), 213-238.

John Harte

27 October, 2012

Earlier this week I gave a talk on the Mathematics of Planet Earth at the University of Southern California, and someone there recommended that I look into John Harte’s work on maximum entropy methods in ecology. He works at U.C. Berkeley.

I checked out his website and found that his goals resemble mine: save the planet and understand its ecosystems. He’s a lot further along than I am, since he comes from a long background in ecology while I’ve just recently blundered in from mathematical physics. I can’t really say what I think of his work since I’m just learning about it. But I thought I should point out its existence.

This free book is something a lot of people would find interesting:

• John and Mary Ellen Harte, Cool the Earth, Save the Economy: Solving the Climate Crisis Is EASY, 2008.

EASY? Well, it’s an acronym. Here’s the basic idea of the US-based plan described in this book:

Any proposed energy policy should include these two components:

Technical/Behavioral: What resources and technologies are to be used to supply energy? On the demand side, what technologies and lifestyle changes are being proposed to consumers?

Incentives/Economic Policy: How are the desired supply and demand options to be encouraged or forced? Here the options include taxes, subsidies, regulations, permits, research and development, and education.

And a successful energy policy should satisfy the AAA criteria:

Availability. The climate crisis will rapidly become costly to society if we do not take action expeditiously. We need to adopt now those technologies that are currently available, provided they meet the following two additional criteria:

Affordability. Because of the central role of energy in our society, its cost to consumers should not increase significantly. In fact, a successful energy policy could ultimately save consumers money.

Acceptability. All energy strategies have environmental, land use, and health and safety implications; these must be acceptable to the public. Moreover, while some interest groups will undoubtedly oppose any particular energy policy, political acceptability at a broad scale is necessary.

Our strategy for preventing climate catastrophe and achieving energy independence includes:

Energy Efficient Technology at home and at the workplace. Huge reductions in home energy use can be achieved with available technologies, including more efficient appliances such as refrigerators, water heaters, and light bulbs. Home retrofits and new home design features such as “smart” window coatings, lighter-colored roofs where there are hot summers, better home insulation, and passive solar designs can also reduce energy use. Together, energy efficiency in home and industry can save the U.S. up to approximately half of the energy currently consumed in those sectors, and at no net cost—just by making different choices. Sounds good, doesn’t it?

Automobile Fuel Efficiency. Phase in higher Corporate Average Fuel Economy (CAFE) standards for automobiles, SUVs and light trucks by requiring vehicles to go 35 miles per gallon of gas (mpg) by 2015, 45 mpg by 2020, and 60 mpg by 2030. This would rapidly wipe out our dependence on foreign oil and cut emissions from the vehicle sector by two-thirds. A combination of plug-in hybrid, lighter car body materials, re-design and other innovations could readily achieve these standards. This sounds good, too!

Solar and Wind Energy. Rooftop photovoltaic panels and solar water heating units should be phased in over the next 20 years, with the goal of solar installation on 75% of U.S. homes and commercial buildings by 2030. (Not all roofs receive sufficient sunlight to make solar panels practical for them.) Large wind farms, solar photovoltaic stations, and solar thermal stations should also be phased in so that by 2030, all U.S. electricity demand will be supplied by existing hydroelectric, existing and possibly some new nuclear, and, most importantly, new solar and wind units. This will require investment in expansion of the grid to bring the new supply to the demand, and in research and development to improve overnight storage systems. Achieving this goal would reduce our dependence on coal to practically zero. More good news!

You are part of the answer. Voting wisely for leaders who promote the first three components is one of the most important individual actions one can make. Other actions help, too. Just as molecules make up mountains, individual actions taken collectively have huge impacts. Improved driving skills, automobile maintenance, reusing and recycling, walking and biking, wearing sweaters in winter and light clothing in summer, installing timers on thermostats and insulating houses, carpooling, paying attention to energy efficiency labels on appliances, and many other simple practices and behaviors hugely influence energy consumption. A major education campaign, both in schools for youngsters and by the media for everyone, should be mounted to promote these consumer practices.

No part of EASY can be left out; all parts are closely integrated. Some parts might create much larger changes—for example, more efficient home appliances and automobiles—but all parts are essential. If, for example, we do not achieve the decrease in electricity demand that can be brought about with the E of EASY, then it is extremely doubtful that we could meet our electricity needs with the S of EASY.

It is equally urgent that once we start implementing the plan, we aggressively export it to other major emitting nations. We can reduce our own emissions all we want, but the planet will continue to warm if we can’t convince other major global emitters to reduce their emissions substantially, too.

What EASY will achieve. If no actions are taken to reduce carbon dioxide emissions, in the year 2030 the U.S. will be emitting about 2.2 billion tons of carbon in the form of carbon dioxide. This will be an increase of 25% from today’s emission rate of about 1.75 billion tons per year of carbon. By following the EASY plan, the U.S. share in a global effort to solve the climate crisis (that is, prevent catastrophic warming) will result in U.S emissions of only about 0.4 billion tons of carbon by 2030, which represents a little less than 25% of 2007 carbon dioxide emissions.128 Stated differently, the plan provides a way to eliminate 1.8 billion tons per year of carbon by that date.

We must act urgently: in the 14 months it took us to write this book, atmospheric CO2 levels rose by several billion tons of carbon, and more climatic consequences have been observed. Let’s assume that we conserve our forests and other natural carbon reservoirs at our current levels, as well as maintain our current nuclear and hydroelectric plants (or replace them with more solar and wind generators). Here’s what implementing EASY will achieve, as illustrated by Figure 3.1 on the next page.

Please check out this book and help me figure out if the numbers add up! I could also use help understanding his research, for example:

• John Harte, Maximum Entropy and Ecology: A Theory of Abundance, Distribution, and Energetics, Oxford University Press, Oxford, 2011.

The book is not free but the first chapter is.

This paper looks really interesting too:

• J. Harte, T. Zillio, E. Conlisk and A. B. Smith, Maximum entropy and the state-variable approach to macroecology, Ecology 89 (2008), 2700–-2711.

Again, it’s not freely available—tut tut. Ecologists should follow physicists and make their work free online; if you’re serious about saving the planet you should let everyone know what you’re doing! However, the abstract is visible to all, and of course I can use my academic superpowers to get ahold of the paper for myself:

Abstract: The biodiversity scaling metrics widely studied in macroecology include the species-area relationship (SAR), the scale-dependent species-abundance distribution (SAD), the distribution of masses or metabolic energies of individuals within and across species, the abundance-energy or abundance-mass relationship across species, and the species-level occupancy distributions across space. We propose a theoretical framework for predicting the scaling forms of these and other metrics based on the state-variable concept and an analytical method derived from information theory. In statistical physics, a method of inference based on information entropy results in a complete macro-scale description of classical thermodynamic systems in terms of the state variables volume, temperature, and number of molecules. In analogy, we take the state variables of an ecosystem to be its total area, the total number of species within any specified taxonomic group in that area, the total number of individuals across those species, and the summed metabolic energy rate for all those individuals. In terms solely of ratios of those state variables, and without invoking any specific ecological mechanisms, we show that realistic functional forms for the macroecological metrics listed above are inferred based on information entropy. The Fisher log series SAD emerges naturally from the theory. The SAR is predicted to have negative curvature on a log-log plot, but as the ratio of the number of species to the number of individuals decreases, the SAR becomes better and better approximated by a power law, with the predicted slope z in the range of 0.14-0.20. Using the 3/4 power mass-metabolism scaling relation to relate energy requirements and measured body sizes, the Damuth scaling rule relating mass and abundance is also predicted by the theory. We argue that the predicted forms of the macroecological metrics are in reasonable agreement with the patterns observed from plant census data across habitats and spatial scales. While this is encouraging, given the absence of adjustable fitting parameters in the theory, we further argue that even small discrepancies between data and predictions can help identify ecological mechanisms that influence macroecological patterns.

Mathematics for Sustainability (Part 1)

21 October, 2012

guest post by John Roe

This year, I want to develop a new math course. Nothing surprising in that—it is what math professors do all the time! But usually, when we dream of new courses, we are thinking of small classes of eager graduate students to whom we can explain the latest research ideas. Here, I’m after something a bit different.

The goal will be through a General Education Mathematics course, to enable students to develop the quantitative and qualitative skills needed to reason effectively about environmental and economic sustainability. That’s a lot of long words! Let me unpack a bit:

General Education Mathematics At most universities (including Penn State University, where I teach), every student, whatever their major, has to take one or two “quantitative” courses – this is called the “general education” requirement. I want to reach out to students who are not planning to be mathematicians or scientists, students for whom this may be the last math course they ever take.

quantitative and qualitative skills I want students to be able to work with numbers (“quantitative”)—to be able to get a feeling for scale and size, whether we’re talking about gigatonnes of carbon dioxide, kilowatts of domestic power, or picograms of radioisotopes. But I also want them to get an intuition for the behavior of systems (qualitative), so that the ideas of growth, feedback, oscillation, overshoot and so on become part of their conceptual vocabulary.

to reason effectively A transition to a more sustainable society won’t come about without robust public debate—I want to help students engage effectively in this debate. Shamelessly stealing ideas from Andrew Read’s Science in Our World course, I hope to do this by using an online platform for student presentations. Engaging with this process (which includes commenting on other people’s presentations as well as devising your own) will count seriously in the grading scheme.

environmental and economic sustainability I’d like students to get the idea that there are lots of scales on which one can ask the sustainability question – both time scales (how many years is “sustainable”) and spatial scales. We’ll think about global-scale questions (carbon dioxide emissions being an obvious example) but we’ll try to look at as many examples as possible on a local scale (a single building, the Penn State campus, local agriculture) so that we can engage more directly.

I have been thinking about this plan for a year or more but now it’s time to put it into action. I’ve been in touch with my department head and got a green light to offer this for the first time in Spring 2014. In future posts I will share some more about the structure of the course as it develops. Meanwhile, if anyone has some good suggestions, let me know!


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