Climate change / global warming

[p2501]

... well explained and scientifically backed.

http://www.teamliquid.net/forum/viewmes ... _id=294083

[Joaz Banbeck]

I will try to tiptoe around the politics, and get to game theory. ( Seems appropriate for a forum like this, right? )

Suppose you have something around 200 members of set A, and all members are faced with event X which harms all parties in time T_X to the extent of cost C_X. ( C_X may not be proportionately distibuted initially, but as T increases, C_X tends toward proportionate distribution. )

Further suppose that to prevent event X, the majority of members of set A must engage in act Y, which has cost C_Y, a cost which the participating members suffer in time T_Y, iff they choose to participate in Y.

If T_Y is rather short compared to T_x, the tendency of most members will be to avoid C_Y, and hope that a majority of other members engage in act Y so that nobody suffers C_X.

Therefore, it hardly matters how certain one is about X occurring. The problem is how to eliminate free riders. This is the 'tragedy of the commons', on a large scale.

[jts]

That is the game theoretical analysis that applies to a single, one-off strategy, with no interaction among the players and strategic options only along a single dimension. The fact that you assume a dichotomous outcome of the game (X or ~X) may also be relevant, in certain analyses.

In fact, Y gets repeated for each period by each player - so we're really talking about Y_(a,t), in a game where a is an element of A and t is the period. Even without official interaction among the players, they can begin to vary their strategies as a way of communicating with one another.

Furthermore, in this particular game (as in many other activities people think about modeling as games) we have plenty of other tools at our disposal. In a simple game, the only way we have of communicating is to punish someone by playing ~Y rather than Y... but in a more complex game the players can keep their message clear by choosing Y and some conceptually separate punishment for people who do ~Y.

[crux]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced? What parts of the science, if any, do you consider uncontrovertible? Are there areas where you think the science is uncertain?

[pwaldron]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced? What parts of the science, if any, do you consider uncontrovertible? Are there areas where you think the science is uncertain?

Yes, I believe global warming is a serious problem, and have held that belief for something like 10 years. It is enough for me that the community of climate change researchers has reached the consensus that global warming is exists and is the result of industrial activity; I defer to that expertise.

[Joaz Banbeck]

...but in a more complex game the players can keep their message clear by choosing Y and some conceptually separate punishment for people who do ~Y.

I don't think that this works. If member A₁ does Y, and A₂ does not, the net advantage to A₂ is 2C_Y. That, in the real world, is substantial, and IMHO, can only be offset by military action, sufficient that C_M > 2C_Y.

[jts]

...but in a more complex game the players can keep their message clear by choosing Y and some conceptually separate punishment for people who do ~Y.

I don't think that this works. If member A₁ does Y, and A₂ does not, the net advantage to A₂ is 2C_Y. That, in the real world, is substantial, and IMHO, can only be offset by military action, sufficient that C_M > 2C_Y.

Well, I'm not sure either why you're doubling the cost (the net difference in income between cooperators and defectors is C per period) or why you think the relative level of income matters. I'm also not sure why you are jumping to military action. You bring to mind John Cleese - "What's wrong with a punitive tariff, boy? Hmm? Why not start her off with a nice punitive tariff? You don't need to go stampeding off to a military strike like a bull at the gate!"

If you look at past treaties that have been concluded - for example, banning chlorofluorocarbons or human trafficking or whatever - I don't think the ratio of costs to benefits, either per person or per nation-state, was greater in those cases than in these. Obviously the cost of action is much larger, but so is the cost of inaction. The main pertinent difference is that, the cost being much higher, those who would be harmed can pay for much more propaganda, so there is much less political consensus and willingness to defer to experts. Around the time of the "hole in the ozone layer", I remember a certain amount of hippy-baiting (like, "Why is ozone bad when we breathe it in our cities, but good when it's in the upper atmosphere? Ho ho ho!"), but no one ever asked me to name the date when I first heard of chlorofluorocarbons, or whether I was sure that they were leaking out of refrigerators rather than volcanoes. But the evidence concerning the ozone layer was extremely dodgy compared to the evidence for global warming.

[Bantari]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced? What parts of the science, if any, do you consider uncontrovertible? Are there areas where you think the science is uncertain?

there are at lest three aspects to what is commonly known as 'global warming':
1. global weather changes
2. possible human-related causes
3. what can/should humans do about it, if anything

here is my opinions:

#1 is pretty obvious, I think. Even within the 16 years I lived in San Diego I can observe changes.

#2 is a political issue.

#3 is the underlying economic issue which is at the bottom of the political debate. doing anything about it would cost big businesses some money (doing things more cleanly is not cheap on a large scale) and so the pro-big-money groups claim that either there is no issue at all or that the issue is not human-made so we should not worry about it. scientifically, i have no clue. you can find scientists on both sides of the question with good arguments, from what i hear, and i don't know enough to judge who is right.

personally, i think that if we have the means to keep the environment cleaner, we certainly should - regardless if the problems are human-made or not. i also think that it would be silly and irresponsible to assume that all that we do to the planet has no influence on what is happening around us. consider all the forests we cut down, all the ground we pave, all the pollution we produce, and so on... whole ecosystems are destroyed by us, whole species extinct or on the brink because of what we do - and this is documented... if all that has no global repercussions yet, it is just a matter of time. so why not do something about it while we still can?

alas... people have the tendency to chase after riches today and to hell with tomorrow.
after all - those who find the riches will also find some nice corner of the planet still green. and the rest of us?... who cares.

[CnP]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced? What parts of the science, if any, do you consider uncontrovertible? Are there areas where you think the science is uncertain?

hmm. Since I successfully completed my university degree in the area (1:1) - or perhaps when I completed my phd in the area. Certainly before having spent the last decade working as a scientist in the area... I guess my 'belief' is more a belief in the scientific method and the experience that scientists in general work very hard at what they do.

What do I consider pretty certain - the basic science behind it. Uncertain? Regional change such country X will experience 73.72% more Y.

[TheBigH]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced? What parts of the science, if any, do you consider uncontrovertible? Are there areas where you think the science is uncertain?

I've leaned towards believing the science for about 10-15 years. I can't pinpoint an exact moment; it's been a gradual process of more and more recognizing the strength of the pro-science side and the weakness of the anti-science side.

[topazg]

... Are there areas where you think the science is uncertain?

That's an impossible question to answer really - All science is uncertain, it's just a matter of "to what degree?"

[crux]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced? What parts of the science, if any, do you consider uncontrovertible? Are there areas where you think the science is uncertain?

hmm. Since I successfully completed my university degree in the area (1:1) - or perhaps when I completed my phd in the area. Certainly before having spent the last decade working as a scientist in the area... I guess my 'belief' is more a belief in the scientific method and the experience that scientists in general work very hard at what they do.

What do I consider pretty certain - the basic science behind it. Uncertain? Regional change such country X will experience 73.72% more Y.

That's interesting. Can you say what exactly you do in the area? Could you elaborate on what you mean by "the basic science behind it" - this could mean different things to different people? Concerning the scientific method, it would be interesting to know what you consider testable predictions of the theory, what observations we could make that would falsify it, and what efforts you know of that are being made to perform such tests.

[crux]

... Are there areas where you think the science is uncertain?

That's an impossible question to answer really - All science is uncertain, it's just a matter of "to what degree?"

That's the interesting question though, isn't it? Let's test people's science knowledge a bit more with a more concrete question, what kind of temperature rise is expected for a doubling of CO2 in the atmosphere? What are the uncertainties in the number?

I was curious whether there would be anwers like pwaldron's which is similar to my own thinking up to maybe 4 years ago: accepting what I was told by the media, and trusting scientists to do the right thing without thinking much about it. I suspect that a large portion of the population believes in global warming without ever having bothered to inform themselves about what exactly either the "official" scientists or the sceptical ones say. Personally, after I became curious and started looking for myself, I found my faith in science somewhat shaken.

What I find instructive is a difference in attitude between (for example) particle physics and climate change. Physicists have the Standard Model, a description of nature spectacularly precise and in agreement with virtually all measurements. The last part of it that hadn't been observed yet, the Higgs boson, was almost certainly found at the LHC last year and nothing that contradicts the model was observed there so far. The LHC may end up confirming the Standard Model in a spectacular fashion - physicists refer to this possibility as the "nightmare scenario". To them, the scientific method means trying hard to falsify a theory because a new observation teaches us something about nature. In contrast, climate science has very shaky models that model nature not very well at all, but in some ways it functions like a church with areas of core dogma that must not be challenged - dissenters are not tolerated. Anyone who makes critical statements is automatically suspect (without evidence) of being in the pocket of evil forces such as Big Oil. Some responses in this thread echoed the belief that action is necessary and it must be industry or big money that's preventing it (as a tangent - I'm sure industry is happy to build offshore wind parks, and banks are quite happy to speculate in emissions trading).

Bantari wrote "Even within the 16 years I lived in San Diego I can observe changes." This matches my own experience, and is one of the reasons that originally made me believe the entire global warming story - the observation that winters in the 1990s seemed to be milder than what I had experienced as a child. Others made the same observation, but here's an amusing classic example of why it's dangerous to extrapolate short-term trends: http://www.independent.co.uk/environment/snowfalls-are-now-just-a-thing-of-the-past-724017.html (a German newspaper also ran a very similar story, http://www.spiegel.de/wissenschaft/mensch/winter-ade-nie-wieder-schnee-a-71456.html (compare: http://en.wikipedia.org/wiki/Early_2012_European_cold_wave).

However, isn't it expected that we can observe changes? It seems to be a form of selective perception to think that a change one has personally witnessed is unusual. If we examine history, couldn't people living at any time in the past have made similar statements? There are lots of examples - the Little Ice Age is well-documented. In the past century, the US had severe drought in the 1930s leading to the Dust Bowl. Arctic warming isn't a purely recent phenomenon, see http://trove.nla.gov.au/ndp/del/article/62428921 or http://trove.nla.gov.au/ndp/del/article/42734540. That was in the 1940s and 1950s... then the world cooled for a few decades and everyone was panicking about an approaching ice age: http://denisdutton.com/newsweek_coolingworld.pdf.

[Alguien]

If T_Y is rather short compared to T_x, the tendency of most players will be to avoid C_Y, and hope that a majority of other member engage in act Y so that nobody suffers C_X.

Therefore, it hardly matters how certain one is about C_X occurring. The problem is how to eliminate free riders. This is the 'tragedy of the commons', on a large scale.

It's much worse than that because you can assume that a large majority of human population will apply the following algorithm:

If (T_x > [my life expectancy]) C_x = 0;

That algorithm is the reason why decisions shouldn't be taken by people but by extra-human entities.

[Bill Spight]

Out of curiousity...

As a question for those of you who believe that global warming is a serious problem, can you say for how long you've held this belief, and how and when you became convinced?

I came to believe that global warming is a problem back in the 1980s, when I became aware of the exponential increases in atmospheric CO2. I already knew about the greenhouse effect and the discovery that Venus is hot as Hades beneath its CO2 cloud. As for thinking that it is a serious problem, I'll say something about that below.

What parts of the science, if any, do you consider uncontrovertible?

I would say none, but I think that it is pretty clear that the world is round and smoother than a billiard ball, that there are tectonic plates, that the sun is fueled by nuclear fusion, that it creates carbon, that there is a Yellowstone super-volcano, that singers can break glasses by means of resonant frequencies, etc.

Are there areas where you think the science is uncertain?

Virtually all of science is uncertain. As topazg says, the question is the degree of uncertainty.

What made me think that global warming is a serious problem? The political resistance to it. OC, there are powerful economic factors at work that put CO2 and other greenhouse gases into the atmosphere at increasing rates. We have built our economies on burning fossil fuels, and we are cutting down trees at a rapid rate, destroying tropical rain forests. Forests help to reduce atmospheric CO2. Changes to stabilize the natural carbon cycle must be widespread, and they will be costly in the short run. Therefore they will meet stiff resistance by those who profit from increasing atmospheric CO2, which is pretty much everybody. Overcoming that resistance is the work of generations. That is why it is urgent now.

Rain forests do not rely upon nutrients in the ground. The forest floor itself is rich in nutrients. Once you destroy a rain forest, the next phase is unlikely to be a grassland. It is likely to be a desert. The soil is simply not rich enough to support much vegetation. It does not even support the rain forest now. I saw on TV (on Nova, I think) several years ago, maybe even in the 80s, a report that in some areas of Brazil where the rain forest had been cleared, local temperatures had risen by 15 degrees Fahrenheit in only a few years.

Eventually humans will live in ecological balance with nature or go extinct. Do we want a future where humans, except perhaps for a favored few, eke out a hard scrabble existence next to our waste products? Suppose that we burn up all our fossil fuel and cut down all our rain forests. (The latter is more likely than the former.) How likely is it that we will have generated a runaway feedback cycle ending in a planetary greenhouse like Venus? Will people die in droves from smog? It is plain that at that point we will have generated ecological conditions that have never existed on earth since we have had an oxygen atmosphere.

Now, I don't think that we will get there. It is a slippery slope argument. Slippery slope arguments are suspect because they ignore negative feedback. But in recent history the forces of negative feedback in regard to the environment have been weak. Around 1980 I watched a Nova show that illustrates the point. During the Dustbowl of the 1930s new conservation techniques for farming were discovered and adopted to help prevent future dustbowls. However, those techniques cut crop yields by 5% by comparison with non-conservation techniques. By the 1980s the conservation techniques had been abandoned, particularly by agribusiness. 5% is too much of an edge to give your competitors. OC, everybody knew that the abandonment of conservation techniques made another dustbowl almost certain in the 21st century. But hey! your competition will be in the dustbowl too.

To me the urgency lies more with human nature than with climate science. We know that we are on a road that ends in disaster. The question is how and when we will put on the brakes. We can do without New York City, Los Angeles, and the Cayman Islands. Too bad about Hawai'i and New Orleans, though. We can even survive our wheat fields becoming desert. We'll adapt. But why should we bring disaster on ourselves?

One night I was driving home, about 50 miles, when a thick fog enveloped the highway. It was a two lane highway in the middle of nowhere, so stopping was not an option. I slowed to below 15 mph and kept an eye on the side of the road. The fog increased my uncertainty about what lay ahead, and I took prudent safety measures. The uncertainty of science is not an argument for barreling on, full speed ahead. If disaster strikes, Whocuddanood is cold comfort.