PMU199H1S: Climate Change - Software, Science and Society
NOTE: This is an old page for the course in the Winter term 2011
Click here for the current course
- Tuesday Jan 25, 2011: Added links to the class blog, and to Steve's blog.
- Wednesday Jan 12, 2011: Hope you all enjoyed the first class. I've posted the graphs I showed down below...
- Wednesday Jan 5, 2011: Draft course outline posted. Comments welcome!.
About the Course
This course will examine the role of computers and software in understanding climate change. We will explore the use of computer models to build simulations of the global climate, including a historical view of the use of computer models to understand weather and climate, and a detailed look at the current state of computer modelling, especially how global climate models are tested, what kinds of experiments are performed with them, how scientists know they can trust the models, and how they deal with uncertainty. The course will also explore the role of computer models in helping to shape society’s responses to climate change, in particular, what they can (and can’t) tell us about how to make effective decisions about government policy, international treaties, community action and the choices we make as individuals.
The course will take a cross-disciplinary approach to these questions, looking at the role of computer models in the physical sciences, environmental science, politics, philosophy, sociology and economics of climate change. However, students are not expected to have any specialist knowledge in any of these fields prior to the course.
General Course Resources
Seminar Notes & Weekly Readings
teaching materials on this website are available for use under a Creative
Commons Attribution-NonCommercial-ShareAlike 2.5 License,
except where noted otherwise. Links to journal articles should work from anywhere
on campus, via the U of T institutional subscription - let me know if they don't. Please respect the copyrights on all material on this site.
As a seminar course, we can be very flexible in what we cover. I've planned a set of core topics that focus on climate models and how they are used, but we can explore much more widely than this if we like.
Part 1: Background & History
- Week 1: Climate Science BC (Before Computers)
- Week 2: Taming Chaos
- Jan 18: Bjerknes, Lorenz, and the basic equations for modeling the atmosphere, with a gentle introduction to Chaos theory.
- Additional notes:
- Week 3: The Giant Brain
- Jan 25: von Neumann, Charney, ENIAC and the first general circulation model
- Here's the figures I used in class this week:
- Background on key people from this week:
- Lewis Fry Richardson - first numerical weather forecast
- John von Neumann - designed the first digital computer & assembled a team for the first computer weather forecast
- Jule Charney - key figure in creating the ENIAC forecasts, later chaired the first US commission that warned of the dangers of climate change.
- Finally some overviews of geoengineering proposals:
Part 2: What do we know, and how do we know it?
And if we can't achieve a massive switch away from fossil fuels across all industry and agriculture, what else can we do? Is geo-engineering viable? (a longer look at this material from week 3):
And finally, to lighten the mood, a fun video:
- Week 4: Any Questions?
- Feb 1: What kinds of questions can we answer with the models? Plus a broader look at the role of science and politics in resolving key questions about climate change.
- Some basic science questions that need observational data:
- A reminder about what kinds of models are available:
- Some experiments that can be done with models:
- Turn off anthropogenic emissions through the 20th Century (from IPCC AR4, WG1, chapter 9. Explanation here)
- Run simulations of future temperature response to difference emissions scenarios (from IPCC AR4, WG1, chapter 10)
- But note: there are different ways of showing the results
- A little explanation of how the experiments are done (from IPCC AR4, WG1, chapter 10)
- Run simulations of future precipation, soil moisture, runoff and evaporation (from IPCC AR4, WG1, chapter 10)
- Explore the impact of climate change on the frequency of extreme weather events (from IPCC AR4, WG1, chapter 9)
- Evaluate the probable values for equilibrium climate sensitivity (from IPCC AR4, WG1, chapter 10)
- Answer questions such as "how do we keep below +2°C of warming?" (from Allen et al, Nature, 30 April 2009. See also trillionthtonne.org)
- Calculate possible emissions pathways to avoid +2°C of warming (from Steve's blog, image originally from the Copenhagen Diagnosis)
- Explore the nature of climate feedbacks (but note, it's really hard to predict where the tipping points are)
- And some things boil down to value judgments and cannot be answered by science:
- Week 5: Planetary Boundaries
- Feb 8: How are we affecting various planetary systems, and how do we figure out what a safe operating space is for humanity? How do policymakers decide on suitable targets for climate policy?
- Here's the slides I used in class this week:
- Week 6: Avoiding Dangerous Climate Change
- Feb 15: Where do greenhouse gas emissions come from, how do we cut down, and can we do it fast enough?
- Here's the slides I used in class this week:
- Keep emissions below 1 trillion tonnes cumulative emissions (ever)
- Get concentrations back down to 350ppm
- Keep temperature changes to below +2°C (or below +1.5°C, as some have advocated)
- A reminder of where Greenhouse Gas Emissions come from (by Industrial Sector) (from the UN Guide to carbon neutrality)
- A simpler breakdown of emissions by industrial sector (from IPCC AR4 WG3 chapter1)
- One way of breaking down the challenge - the stabilization triangle (from Princeton U's Carbon Mitigation Initiative)
- ...and the idea of stabilization wedges (from the same place)
- but of course, emissions stabilization isn't enough, so we need more wedges (analysis from National Geographic - see also the learn more section)
- To explain that each wedge starts small and builds over 50 years (from the presentation at CMI)
- Another view of a set of possible stabilization wedges (from Stenger's blog)
- Where we waste energy - an example of how much energy it takes to power a lightbulb (from IPCC AR4 WG3 chapter 4)
- Passive Houses - houses that need no heating system (from the Wikipedia entry on Passive Houses)
- Electric Cars: The Toyoto Prius, a hybrid electric vehicle, and the Chevvy Volt, a plug-in hybrid electric vehicle
- But batteries have a long way to catch up with the energy density of petroleum & Diesel (from Toyota's analysis)
- And the Moore's law for battery technology is much slower than for computers - doubling every 10 years (from a comparison by Kevin Kelly)
- So we also need to look at changing how people travel (from IPCC AR4 WG3 chapter 5)
(Break for reading week)
Part 3: Choosing and Using Models
- Week 8: Experiments, Models, and Modeling Experiments
- Mar 1: Experiments with CO2, and Experiments with simulation models
- Here's the videos of experiments I used:
- And here's the slides I used about models and experiments:
- A ridiculously simple model - the bathtub (from National Geographic)
- The bathtub simulator - have a play! (from Climate Interactive at MIT. See also the Momentum Simulator, and for more explanation see this short paper and a longer one from John Sterman)
- putting together a model of the globe (as a jigsaw puzzle)
- A schematic of the main relationships we might want to model (from Flickr user ClimateSafety)
- Basic energy balance model (from IPCC AR4 WG1 FAQ1.1)
- A schematic of the different timescales we might be interested in (from McGuffie & Henderson-Sellers, 2005, p74)
- A schematic of different processes on both time and spatial scales (from Prof Dudley Chelton)
- Another view of the hierarchy of model types (from McGuffie & Henderson-Sellers, 2005, p51)
- Another schematic of different types of model (from an overview by David Kemp)
- A comparison of climate and integrated assessment models (from Moss et al, Nature, 11 February 2010)
- A reminder of how general circulation models work (from CMMAP's primer)
- A single column model, which can be compared with single column measurements (from ARM)
- The Bretherton Diagram: a conceptual model of earth system processes
- A diagram explaining the increasing resolution of the models (from the UK Hadley Centre)
- Increasing resolution of climate models over the four IPCC assessments (from the IPCC AR4 WG1, chapter 1)
- Development of climate models to include more earth system processes (from CSIRO's overview)
- Architecture of a coupled climate model (from Easterbrook and Johns, 2009)
- Example coupled model: The Community Earth System Model (CESM)
- Simpler model for running on a desktop: Educational Global Climate Model (EdGCM)
- Example Integrated Assessment model: Climate Rapid Overview and Decision Support (C-ROADS)
- Simplified version, runnable in a web browser: C-Learn
- For more background on models, see:
- Week 9: Experimentation
- Mar 8: How to run a model
- Here's the visualization of the growth of CO2 that we watched:
- We spent most of the seminar getting familiar with EdGCM:
- Week 10: How good are the models?
- Mar 15: testing, validation, and doing science
Part 4: What we can know, and what we can do
- Week 11: Knowledge and Uncertainty
- Mar 22: Can we trust the models? Can we predict the future?
- Well, we didn't get to have this seminar, but here's some things we would have talked about:
- Week 12: Decisions, Decisions, Decisions
- Mar 29: What policymakers need, and what they get.
- Week 13: Enough talk, time for action!
- Apr 5: Managing the Earth's systems - what should we be doing about climate change, and what other tools do we need to be successful?
We can include any of these based on interest and enthusiasm (but probably not all of them!). Some of these stray away from the "computing" them of the course, so we might need to agree on some criteria for which ones to include. In no particular order:
- Carbon calculators (and other software for personal/community decision support);
- Data Collection for weather and climate: how the global observing system works;
- Supercomputers and the path to exascale computing;
- Media potrayals of climate models and their projections;
- The role of Free/Open source software in climate science;
- The carbon footprint of computing
- Other sources of evidence about climate change: paleoclimate, observational data, measurable impacts
- Controversy and disinformation - how do you know who to trust? Is there really a debate, and if so, what about?
- How bad will it get?
- Climate Change and other global issues: over-population, peak oil, conservation of ecosystems, international conflict, food security, renewable energy, etc.
- Climate Ethics: inter-nation and inter-generational issues
There are four assignments for the course:
Prepare a 10-minute power point presentation (in teams of 2).
Due Feb 18th. Worth 20%
Design an experiment.
Due March 18th. Worth 15%
Due April 7th. Worth 40%
- Research a topic related to the course and write a blog post about it.
Due Jan 28th. Worth 15%
- Detailed instructions coming soon
Plus 10% of the course mark is for showing up for seminars and tutorials, and participating in the class blog (as you asked for it!)