This talk by Jeremy Jackson nails the causes, severity, and urgency of our overshoot, and what we need to do in response.
Here is a classic by physicist Tom Murphy.
This is my favorite talk on limits to growth, the most important topic almost no one discusses, including people who should know better, like the Green Party.
Note that Murphy does not mention the explosive worldwide growth in debt, which is the only reason the game has continued longer than engineers like myself predicted it should.
The problem with our reliance on debt is that when the correction comes, it will be much more violent and damaging than it needed to be, which is another topic that the Green Party, and almost everyone else, does not discuss.
In summary, the most important things we should be discussing, are the things we never discuss.
Isn’t that an amazing behavior for an otherwise intelligent species?
This is a review of James Hansen’s 2009 book “Storms of My Grandchildren”. James Hansen is the most respected climate scientist in the world. He is naturally shy and avoids publicity but decided to write this, his only book, after the birth of a grandchild. He wanted his grandchild to know later in life that his grandfather had done everything he could to warn the world. I’m of the opinion that Storms of My Grandchildren is the definitive book on climate change.
The density of information in the book is very high so it won’t be possible for me to summarize all of it. Instead I will try to convey the big takeaways for me. Hansen did a remarkable job of summarizing all of the important science. This science is much more complex and nuanced than I had previously thought. I was surprised how deep our understanding is, and the stability of the foundation upon which it rests. I was under the mistaken impression that most predictions had been drawn from computer models, the accuracy of which is of course dependent on model assumptions. It turns out that most of the important predictions are drawn from studying climate change throughout the geologic history of our planet, and they know a surprising amount about past climate.
Before I discuss Hansen’s conclusions, I need to digress for a moment. Experts in the fields of energy, economy, and climate tend to have narrow fields of view. Economists generally know very little about or deny the physical realities of energy and climate. Energy experts frequently dismiss climate change or are ignorant of the science. Climate scientists frequently do not understand or include the implications of peak energy and peak debt in their forecasts. These blind spots are remarkable given the intimate inter-dependencies of energy, economy, and climate.
James Hansen is no exception. From his book I conclude that he does not understand the implications and timing of peak oil, and seems to be unaware of our monetary system mathematics that guarantee collapse in the absence of growth. Therefore it is very important to place Hansen’s climate predictions in the context of his energy and economy assumptions.
Hansen assumes the economy (and hence energy consumption) will continue at roughly its current level. He makes a very compelling case that if we continue to burn coal, oil, and natural gas at the current rate, then global warming will make the lives of our grandchildren miserable at best, and unlivable at worst. The most important impacts being significant sea level rise, agriculture disruption, storm damage, and species extinction.
He further asserts, with no uncertainty, that if we burn all of the remaining coal plus non-conventional oil (tar sands and oil shale) then the planet will experience runaway warming and will end up like Venus with all life extinguished.
Hansen concludes (with supporting analysis) that there is only one possible solution to maintain a planet that is hospitable (if somewhat damaged) for our grandchildren:
1) We must reduce CO2 from today’s 392 ppm to below 350 ppm, and very soon. It was refreshing to hear him acknowledge how difficult this will be. For example, every single country that signed the Kyoto protocol, which promised CO2 reductions, actually saw CO2 increases, and CO2 is still increasing today. Furthermore, even countries that signed with honest intentions and worked hard on renewable energy and conservation, like Japan, still saw CO2 go up. In case you are puzzled by this, it is exactly what one would expect given that GDP is proportional to energy consumption, and 90+% of our energy comes from burning fossil fuels.
2) To achieve 350 ppm we must stop all use of coal, plus stop non-conventional oil (tar sands & oil shale), plus implement a carbon tax, plus stop deforestation, plus control population growth. Again, it was refreshing to hear him acknowledge that we cannot stop using our remaining conventional oil because there is no alternative and because we will need it for the following step.
3) To maintain civilization as we know it, and to have any hope of public support, we must replace most of the electricity that was previously generated by coal. Again I was impressed that Hansen understands that the low power density and intermittency of solar and wind eliminates them as candidates for coal replacement. Hansen says our only choice is nuclear. But current nuclear produces too much waste and consumes too much depleting non-renewable uranium. Therefore we need a crash program to develop 4th generation nuclear and a little luck. If successful, 4th generation nuclear will burn waste from today’s reactors and will produce very little new waste.
I have studied energy in sufficient depth to know that Hansen is correct about the need to replace coal with nuclear, assuming lifestyles as usual. More specifically, I agree with Hansen that when you hear people promote clean coal (which means carbon capture and storage) you can rest assured that this is green-wash that will never happen for a variety of solid technical and economic reasons.
It’s worth reflecting on the precariousness of our grandchildren’s situation, when the only possible solution that maintains current lifestyles and a livable planet requires a new nuclear technology that is still in the R&D phase and may not work.
But now we need to circle back and revisit his initial assumption that the economy (and hence energy consumption) will continue at roughly its current level. As you know from my analysis of energy and the economy, I am certain that we are facing a global collapse. What does this mean for Hansen’s climate prediction and prescription for avoiding a disaster for our grandchildren?
When collapse occurs we can conservatively expect half of the wealth and economic activity on the planet to be wiped out. And it’s entirely possible that the decline will be much deeper than 50% given the huge levels of debt and derivatives that need to be unwound. This means that there is no chance of us being able to afford the nuclear replacement of coal given the many trillions required for the switch. Which means we will continue to burn coal but at a reduced rate because of reduced economic activity. Will this reduced energy consumption be sufficient to save our grandchildren?
But it gets more complicated. At the end of his book Hansen summarized the key uncertainties in our understanding of climate science. One of the big uncertainties is the effect of aerosols on the earth’s energy balance. Aerosols are the particulates (soot) that are emitted from the combustion of coal and diesel and other industrial processes. Aerosols tend to mask the effect of CO2 by blocking sunlight. But unlike CO2 which remains in the atmosphere for centuries, aerosols fall out of the sky after a week or so. So when economic collapse occurs, we can expect energy production and industrial activity to dramatically drop and thus aerosol production to dramatically drop. Which means that in a very short period of time we will experience increased effect of our CO2, which means we may experience a global warming “surge”.
Climate scientists acknowledge the presence of a tipping point beyond which the climate will warm no matter what we do. Many scientists are very scared that we are close to this tipping point. Hence Hansen’s call to arms for us to get back below 350 ppm. Will the warming surge caused by economic collapse push us past the climate’s tipping point?
So now let me try to sum this all up.
If you do not believe Hansen’s predictions and prescriptions, then you really should read his book. It is very persuasive and I think it will give you confidence that he knows what he is talking about. In fact you should read it regardless. We all need to understand this stuff given the stakes.
If you do not believe that the economy will collapse, and you believe Hansen’s science, then you know exactly what needs to be done. You should push the Canadian and Alberta governments to shut down the tar sands immediately. You should push for replacing all of our coal-fired power plants with nuclear plants. You should support a carbon tax. You should support sending aid to developing countries to discourage deforestation. And you should support government policies to control population growth.
If, on the other hand, you believe my prediction of economic collapse, then our actions are less clear. We need to ask our scientists to answer the questions: 1) How much economic activity reduction is required to get us back to below 350 ppm? 2) What are the implications of a sudden drop in aerosols? With answers to these questions we can derive any further actions required to protect our grandchildren. Hopefully nothing more will need to be done than to survive a permanent economic depression.