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70th Anniversary Celebratory Conference, Oxford, UK

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“Theology and Science of Creation,” Madrid, Spain

Episode 12 "The World Set Free"
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5/26/2014 at 12:08:39 AM GMT
Posts: 130
Episode 12 "The World Set Free"
This topic is devoted to episode 12 of Cosmos: A Spacetime Odyssey


6/2/2014 at 2:12:01 PM GMT
Posts: 51
Speaking from the peanut gallery, since I am far from any climatologist, this episode seems to present very nicely, with exceptional graphics, the arguments favoring global warming due to human intervention. Their purple coloration, for instance, of CO2 emission served well to remind me of their earlier episode about lead contamination, which was indeed a major health issue and a likely great analogy for today's contamination of CO2. [It is hardly any wonder why they spent much time on the lead discharge topic.] This is, nevertheless, clearly a sales presentation. Because of its importance, I don’t fault them for that, though, like most sales presentations, does it not come with a bias?

I personally would have liked deeper answers from this episode. I think it is today, in fact, that we will see White House executive actions that will attempt to improve our wasteful discharges but also adversely affecting, no doubt, our cost of energy.

So my questions coming from this episode are:
1) Is the claim true that there is nothing controversial about human’s responsibility for global warming?

2) If so, is that a belief in “science by consensus”? What about the arguments from the few prominent scientists that do disagree?

3) Was there really a time when the world was “not too hot or cold”? Didn’t we recently (geologically speaking) come out of an ice age without anthropogenic assistance? My point is that the episode implies a longevity to a "just right" period.

4) Do we really know the Sun has no responsibility for climate change? The invariance of the Solar Constant certainly suggest this is true, yet the Maunder Minimum -- when essentially the Sun was almost void of sunspots and thus less active – correlates with the “Little Ice Age”. That still strikes me as a little too coincidental. I would have liked more of a scientific accounting on their part, but their false-colored Sun was certainly attractive. [I wish someone would have taken my heliochromological bet. :)]

5) Is it remotely fair to claim a particular butterfly is causal to a future storm in Maine?

6) What about other variables that might, or might not, come about due to warming that would trigger a cooling effect? Will increased moisture increase our planet’s albedo, thus causing a cooling effect? Will more snow-fall occur in lower latitudes with similar effect?

7) Where is the climate model itself? I am slightly familiar with the Big Bang/Inflationary model(s), at least to the point I am confident they are established, but is there a computer somewhere that has “The Climate Change" model that allows normal scientific scrutiny so that it can be falsified with objective tests? Does this model hold-up to retrodictive tests?

I liked the dog wandering analogy for weather but what is the true size of our weather dog, relative to the "mass" of our climate? How long is the weather leash and is the ground they walk that flat or are there cliffs ahead?

I was a little bothered with the butterfly story since I do not see the “Butterfly Effect” as they, and Wiki, represent it. To me it is far more about not being able to attribute a single extremely trivial initial condition to a major outcome. If we knew every insects wing action as an initial condition for a super model, we still would not be able to predict the next storm location, right? Newtonian determinism fails at this level, at least as I understand it.

The CO2 story is a big one in many ways. I hope all that I need to know comes my way someday on the evils of CO2, but I won't hold my breath.


Last edited Monday, June 02, 2014
6/2/2014 at 3:18:37 PM GMT
Posts: 41
Great lead in to the discussion on this topic, George. I'm sure I'm certainly less a climatologist but I think you made good points/observations all around.

I had a bit of skepticism going into the show, partly from a conservative bias and partly from the news reports in the last couple years about discrepancies found in some of the data on topic at the big meetings. But, I found the "sell" fairly persuasive. They anticipated most of my questions.

The estimates of the actual amount of CO2 we put in the atmosphere per year compared to volcanoes and the like was pretty compelling. But, of course, it is a complex picture and I look forward to see how others respond to your points on some of the issues.

Here's an idea: exterminate all the butterflies in the world and we won't have to worry about hurricanes
;-o)

 Good points on that, George. Perhaps it is possible, however remote, if all the tipping points converge by coincidence, but I've heard the "Butterfly Effect" used a little too often lately and think it strains credibility on an otherwise serious topic.



Last edited Monday, June 02, 2014
6/2/2014 at 4:20:21 PM GMT
Posts: 12
@George
It's not so much a case of Newtonian determinism failing, but that the dynamical system is chaotic - namely, the set of partial differential equations describing the system are non-linear, usually driven, and dissipative to boot. This can lead to exponentially divergent solutions for two nearby sets of initial conditions. The system's behaviour is still determined by the equations of motion as expressed by its differential equation(s) and initial conditions - google for chaotic dynamics and nonlinear systems to get a better treatment.
Thus, when meteorologists use their global weather models to predict the weather, they are feeding those models with data sampled at finite grid points over the earth's surface - the finite sampling means that there are inherent uncertainties in the initial conditions, so the computed model solution diverges from the real system over time. In fact, if one computes the solutions for different sets of initial conditions within the range of sampling uncertainties, one ends up with different results for the future weather, and those differences increase very quickly as one iterates the solution forward in time.  Just how different they are depends on the region of phase space that they start out in - if the region is in an island of stability or an attractor (see the Lorenz Attractor) of some sort, then the divergence is bounded.

The 'Butterfly Effect' is something of a tongue-in-cheek statement in chaotic dynamics circles, and kind of like Rutherford's comparison of 'shooting a 15-inch shell at a piece of tissue paper and having it bounce back at you' with his alpha-particle / gold foil scattering experimental observations. The fact that the earth's weather is a non-linear, driven, dissipative system would mean that such small perturbations would probably be damped out too quickly to have the effect that is ascribed to it.

This episode was a bit better than the rest on content, but not by much - it seems that the series spends more time on scientific conclusions and interpretation of results (the interpretation that they want to impose) than on the details of the science itself, never really getting much deeper than what an introductory 'Science for non-science-majors' course would.


Last edited Monday, June 02, 2014
6/2/2014 at 5:25:03 PM GMT
Posts: 23
"Here's an idea: exterminate all the butterflies in the world and we won't have to worry about hurricanes
;-o) "

You don't need to exterminate all of them. Just hunt down that one butterfly in Maui that they mentioned in the episode. That's the one that caused the storm in Maine. Somebody should make sure it ceases its destructive flapping.

Seriously, though. The chaotic systems that Dassen describes above actually do predict this even though there is obviously no way to test such a thing. You can also think of it as virtually infinite sensitivity to initial conditions. Shoot a pool ball at a scattered assortment of balls on the table that bounce around for a while and it is easy to model on a computer how an alteration of the initial cue ball vector by a millionth of a degree seems at first to make no discernible difference until a few sets of collisions in when the error amplifies and rather suddenly you have a totally different configuration unfolding. So next time you are deciding whether or not to stifle that sneeze, you might pause to wonder what tornado might miss (or not miss!) a town because of your decision. Obviously this is of no practical use other than feeding musings like these.

On a more practical level, I thought this episode to be a shining star of the series so far. I really appreciated his distinctions between weather and climate. I'm already thinking how I can work that notion in to my own science classes next year. To George's question about the dog, I imagine the weather is quite a wide-roaming dog. An on-line poster was making the rounds showing a man speculating that ... "Global warming must not be happening because it is cold out ... right here ... today." The classic "one-data-sample" extreme this satirizes is where we science teachers really need to be stepping in. This "dog" is quite a large roamer so that even what are larger sample sizes can be enlisted by deniers to cast doubt.

Possibly echoing one of George's questions I also wondered if there are any negative feedback variables that can help out. We only heard of all the dangerous positive feedback effects towards warming. But if the earth has ever reached extreme warming in the distant past, what was it that brought it back out?


6/3/2014 at 6:16:40 AM GMT
Posts: 16
In general I thought the episode was very good. My main critique is that I think Tyson is overly optimistic that we can switch 100% to renewables now. Fossil fuel combustion for our energy needs has a massive infrastructure. It will not be replaced overnight. There are some technical/materials obstacles to solar and wind power that seldom are mentioned. For example, rare earth metals used in high power wind turbines have their own mining and manufacturing hazards. Solar is just getting off the ground. I was disappointed that he didn't complete the arc from Hiroshima to Apollo to nuclear power. Advances in efficiency, natural gas replacing coal, carbon capture and sequestration are all part of the formula. In other words we need an all of the above approach. Such a sane approach seems to be what the Obama administration is pursuing.

[WARNING: Shameless plug] Many of the issues in this episode are discussed in my eBook Energy: What the World Needs Now (co-written with Tony Rappé--more info at http://www.energywhattheworldneedsnow.com). Our chapter on "The Problem of CO2" goes into a bit more detail (and alone is worth the price of the book) than COSMOS did but is still accessible, we hope, to a non-expert audience.

The purple CO2 sequence was great but keeping it as a gas doesn't give it the force if it were a liquid. After all, globally we quite tolerant of smog. In our book we describe CO2 as a green goo that never goes away and accumulates in our streets. We have a sense of how much gasoline we put in our vehicles. Multiple by 3 to get the amount of CO2 that comes out of the exhaust. Imagine if we had to take that to the landfill every time we filled the gas tank. I encourage my students to think about where there stuff goes. There's no such thing as emptying the trash (except on your computer).

I did like the fact that he emphasized the importance of the greenhouse effect for keeping earth's surface temperature suitable for liquid water (and life as we know it). While it could have been emphasized more, I was glad to see an admission that our energy use has been critical for civilization as we know it and that we can't (or shouldn't just turn it off). 

He referred to the correlation between the amount carbon released from fossil fuel burning since the beginning of the industrial revolution and what is found in the atmosphere. It is a first year chemistry calculation and is fairly straightforward. It turns out that the increase in atmospheric concentration of CO2 is only half of what you expect if it were irrevocably added to the atmosphere. The rest is dissolved in the ocean and in plants. So it could be worse!


6/4/2014 at 8:00:28 PM GMT
Posts: 130
It was an excellent episode, very well presented and illustrated and easy to follow. Yes, there were quite a few places where it would have been nice to have more scientific depth but for a general audience it was well done. I too liked the purple carbon dioxide animation. It's much easier to ignore that which is invisible.

Victoria, thanks for putting the right perspective on the "butterfly effect." It isn't meant to be taken literally. If one doesn't take Genesis 1 literally, why would one take the butterfly effect literally? After all, there are billions of butterflies flapping their wings around the world. But it does illustrate the chaotic nature of weather and the sensitivity to initial conditions.

The dog/man analogy of weather/climate was new to me too and I thought it was clever. George, a rough estimate of the size of the "dog" vs the "man" can be done from any weather report. Take the difference of the max and min temp for a given month and compare it with the difference between the average temperature for the month and the normal average. That would be an estimate of the "size" of weather vs climate.

George, your set of seven questions are well written and deserve a coherent response. I'll try some of them later when I have a bit more time. Maybe others will help as well.




6/5/2014 at 5:07:29 PM GMT
Posts: 16
A corollary of the "butterfly effect" is that certain butterfly contributions prevented some hurricanes. As Victoria pointed out even if the system was deterministic, it is the finite sampling of the initial conditions that is the problem here. Thus, we are doing our deterministic calculation from a mere approximation of the initial conditions.

Concerning Victoria's comment about going deep... COSMOS IS a "science for non-majors" presentation. If you watch the release day Q&A event (http://www.cosmosontv.com/live-event), you get a sense of this. (You also get a good sense of the principal's religious views.) As one who has taught "science for non-majors" courses, I would say this is an appropriate presentation for the intended audience. The weakness of this style of presentation is that critics of a particular viewpoint (as in climate change skeptics or evolution skeptics) can counter with criticisms that are very scientific sounding because they throw lots of numbers and jargon at "non-major" (as if the others aren't able to do that too). The "non-major" is impressed by the mere force of the scientific sounding criticism and doesn't take seriously the mainstream claim.

Here's where I think "consensus science" has some merit. Let the critics convince the scientific community in the technical literature. We all know that scientific fame and fortune go to those who overturn cherished beliefs. Critics are usually marginalized because they have not been successful in convincing their peers.


6/5/2014 at 8:44:12 PM GMT
Posts: 130
Originally posted by G. Cooper:
So my questions coming from this episode are:
1) Is the claim true that there is nothing controversial about human’s responsibility for global warming?

Yes, at least within the community of people working and publishing in the field.

2) If so, is that a belief in “science by consensus”? What about the arguments from the few prominent scientists that do disagree?

I would say it's the compelling arguments from 97% of those working in the field vs the unsubstantiated questions from those not working in the field. Those arguments have been addressed and settled by the experts, as far as I know.

3) Was there really a time when the world was “not too hot or cold”? Didn’t we recently (geologically speaking) come out of an ice age without anthropogenic assistance? My point is that the episode implies a longevity to a "just right" period.

It's been too hot and it's been too cold so presumably it's been "just right" in between but that's a misleading concept. Just right for what? or whom? The holocene has been unusually stable in terms of temperature for the last 10,000 years so we've adapted very well. Indeed, all fluctuations until recently have been without major anthropogenic assistance.

4) Do we really know the Sun has no responsibility for climate change? The invariance of the Solar Constant certainly suggest this is true, yet the Maunder Minimum -- when essentially the Sun was almost void of sunspots and thus less active – correlates with the “Little Ice Age”. That still strikes me as a little too coincidental. I would have liked more of a scientific accounting on their part, but their false-colored Sun was certainly attractive. [I wish someone would have taken my heliochromological bet. :)]

Yes. and no. Obviously, the sun has the dominant role in climate change by being the primary source of energy, with radioactivity being a distant second. And you know better than the rest of us about Milankovitch cycles. But the solar radiation changes slowly--very slowly--and we can measure the radiation in the recent past. It's been essentially flat and changing very little. The faster 11 year cycle due to sunspots isn't a major factor and it can easily be separated out. Those who do argue for the possibility of the sun being responsible for the latest global warming claim it is due to an interaction of the sun and cloud formation and similar factors. But no evidence has been obtained for such processes as yet.

5) Is it remotely fair to claim a particular butterfly is causal to a future storm in Maine?

NO!

6) What about other variables that might, or might not, come about due to warming that would trigger a cooling effect? Will increased moisture increase our planet’s albedo, thus causing a cooling effect? Will more snow-fall occur in lower latitudes with similar effect?

Water vapor is a much stronger greenhouse gas than carbon dioxide or even methane. But there's a huge difference. Water precipitates out above a saturation limit while CO2 lasts for 500 years or more. So water isn't the problem. But as CO2 warms the atmosphere, the water saturation level increases and that adds to the greenhouse effect.
You are really asking about negative feedback loops and there aren't any imminent major ones that I've heard of.

7) Where is the climate model itself? I am slightly familiar with the Big Bang/Inflationary model(s), at least to the point I am confident they are established, but is there a computer somewhere that has “The Climate Change" model that allows normal scientific scrutiny so that it can be falsified with objective tests? Does this model hold-up to retrodictive tests?


Your question uses the term "model" in two different senses. For the Big Bang, the term "model" is closer to a theory which has a lot of evidence for it. In the case of climate "models" the term means simulation as in computer simulation that seeks to determine the implications of known physics in an extremely complex multi-dimensional system. So there are many models and usually the IPCC and others rely on the range of modeling results, tending toward the conservative side. Yes, those models are always developed with retrodictive sanity checks but that still doesn't guarantee future results. The system is far too complex for that. Much of the skepticism expressed by Freeman Dyson, for example, is based on the assumption that models can't reliably account for that complexity. Which is true to some extent but the trend of the results as the models are improved over time is very clear. The effect is getting stronger as we understand it better, not weaker. It's not going away as the accuracy increases.

I'm sure someone will be kind enough to differ with my responses!!! That's fine. It's an interesting topic of discussion on a very important issue.


6/5/2014 at 9:30:35 PM GMT
Posts: 12
@Terry Gray
I get what you are saying regarding my comments about the show not going deep enough.  Sure, it is designed for that type of audience, but....

The reason I say this is due to some of the comments I am hearing from some of my friends who think the sun rises and sets on NGT - they are non-science people with a keen interest in all things scientific and think science is the last word on everything. Moreover, they are equally convinced that ScienceTM (which amounts to Scientism/Metaphysical Naturalism - not that they would understand that either) has disproven religion in general. They accept as true, uncritically, everything that NGT says, without really understanding the science itself.  How many non-science people in the audience really understand why Newton's formulation of the gravitational force (inverse square, central force) implies that the orbit of a planet about the sun is an ellipse (or more generally, a conic section), or even why the symmetry of the force (spherically symmetric) leads to conservation of angular momentum?  This is to say nothing of the deeper issues of the relationship between the symmetry properties of a system and conservation of the corresponding dynamical variables (Noether's Theorems).  If you ask them, they'll recite the answer, but ask them to explain the deeper reasoning and they are without a clue.  Then they might read this article by Tyson:The Perimeter of Ignorance and ask me how I could be a Christian and a physicist - sometimes that just becomes annoying and I (gently, I hope) remind them that their understand of both is superficial at best.

So my concern is that the series will engender an illusion of understanding and the uncritical acceptance of the worldview that the series is subtly promoting.