Monday, September 10, 2007

On certainty

Some questions to the reader:
Can science prove human causation of global climate change? If so why are we still arguing about it? If not, is there any scenario in which we can accept some degree of scientific uncertainty? Has the bulk of scientific opinion been wrong before? If so, does this make science unreliable? Is it somehow foolish or ethically wrong to accept benefits from science without question, but shun science’s warnings?

13 comments:

Chris McClure aka Panhandle Poet said...

Science and global warming is one of those issues that has become politicized to the point that it is difficult for the layman to determine with reasonable certainty whether the global warming is man-made or from natural cyclical causes -- or possibly a combination of both. The fact that there is continuing debate leads me to the conclusion that the answer is yet unknown.

My training as an economist makes me comfortable with uncertainty. Many "answers" to economic questions are a matter of probability. Probability has also been introduced into such "hard" sciences as physics through quantum mechanics.

My personal opinion is that we are in a warming phase of a natural global weather cycle. I believe it is entirely likely that human activity has had a minor impact on that cycle and may perhaps be accelerating the transition to a warmer general climate. I do not adhere to the idea that the effects will be cataclysmic except to the extent that if you build in a flood plain you should expect periodic flooding.

I believe we can expect shifting climate patterns to which humanity and "nature" will adapt. I don't believe it will happen as depicted in many disaster movies. There will be individuals who profit from the media-incited hysteria as events unfold. The majority however will pragmatically adjust to the changes.

What are your views on climate change? If you accept that we are entering into a warm phase, do you belive it to be man-induced?

Pat Jenkins said...

pan's comments leads me to exactly what i was going to ask you erd. what does science do with the unexplainable? does it not have it's limitations?

David said...

panhandle poet,
The uncertainty you describe is certainly typical of the social sciences and of engineering, and as you point out, is increasingly used in many natural sciences. Among these natural sciences that are perhaps most apropos to this discussion are ecology and climatology. Both of these disciplines commonly use methods familiar to economics to reach conclusions.
Regarding "The fact that there is continuing debate leads me to the conclusion that the answer is yet unknown.": In this statement, who (what people or groups) do you see as having the debate?
Regarding "I believe we can expect shifting climate patterns to which humanity and "nature" will adapt.": How long do you suppose it will take for humans and nature to adapt? What do you see as the necessary adaptations?
I’m curious as to why you believe that any contemporary climate change is substantially natural and not anthropogenic.

David said...

PJ,
What do you mean by "unexplainable"? Do you make a distinction between the unexplained and the unexplainable?
The questions in this post are about the limitations of science and the differences between positivism and post-positivism. What do you think the limits of science are?

Chris McClure aka Panhandle Poet said...

e.r. Re "continuing debate" - it is occuring at the political level and at the scientific level. Much of the debate at the scientific level is, I believe, politically motivated - on both sides. The preponderance of evidence indicates warming yet the cause of the warming remains uncertain.

As to "adaptation" to the change - the speed of adaptation will be totally dependent on the rapidity of change -- which is as yet unknown. Change occurs daily. Human behavior is already adjusting with the anticipation of warming through the accelerated exploration of alternative energy sources. Will the polar bears disappear? Possibly. Will they reappear during the next ice age? Probably. I suspect the genetic potential will reside within surviving bear populations.

What adaptations will be necessary? I think we will see population movement inland from the coasts if indeed we see a significant rise in sea level. I think we will see shifts in agricultural concentrations - especially of specific crops - based on changed weather patterns. I think we will continue to see parts of the world with underdeveloped economies and other parts that take full advantage of available resources. I think we will see an increasing emphasis on sustainability in all production processes due to a heightened awareness of the limitations of natural resources. I expect to see the extinction of species and the emergence of new varieties within species. I believe in the resiliency of the human species and of the planet in general.

My belief that climate change is natural is based on an evaluation of the deep history of the planet. We can't base our judgment on the past 200-300 years, we must look at geologic time -- 10's of thousands of years. There is the same amount of carbon on the planet today as there was a few million years ago. The only difference is its location. We are releasing carbon into the atmosphere. So do volcanoes. So did the dinosaurs or later the mastodons and other early mammals. Carbon is released; it is sequestered. It is natural and normal. How much carbon do ants release into the atmosphere? The total biomass of ants is greater than that of humans. Why don't we blame global warming on ants? The earth and all that is in it or on it is composed of interlocking systems that work together for the most part. The great fiery engine that we call the sun provides the energy input that drives it all. What cosmic forces are acting on the sun that are impacting the weather on earth? I think there continue to be too many unknowns. I'm certain that only a small part of it will be revealed in my lifetime. What are your thoughts?

Pat Jenkins said...

boy you ought to love this erd... with two of us entering the debate you can expound until your heart is content, now to my response. science has failed through no fault of it's own, to be able to verify or explain some certainties. and i will use a black hole as an example. so as science attempts to prove things.. gw.. evolution... etc.. and doesn't have a singular event to point to of truth, what does it then do?

David said...

panhandle poet,
The question about who is engaged in the debate is intended more about specific people or groups than it is about generalities. The political debate is largely generalized. However, in the scientific arena, who do you perceive as arguing for and against?
With respect to polar bears, if they become extinct, they will not naturally re-emerge. Some other organism may ultimately fill their niche, or humans may artificially recreate polar bear populations within their historical ranges, but there can’t be a new wild population if they’ve all died.
With respect to crop migration, do you see a significant change in agricultural capacity? After all, soil takes considerably longer to develop than the climate is expected to, and much of the most productive agricultural land exists in modern flood plains and deltas; significant changes in hydrology and rising oceans would make much of this land unusable.
Regarding “We can't base our judgment on the past 200-300 years, we must look at geologic time -- 10's of thousands of years.”: The discipline of paleoclimatology looks into the geologic past. The significance of the last 200-300 years is that in this time humans have been converting sequestered carbon into atmospheric carbon. The difference between different climatic periods and natural variation therein is the subject of a great deal of study within this discipline. Who is arguing that we shouldn’t look more than 300 years ago?
Regarding the location of carbon, dinosaurs, volcanoes, ants, &c: The amount of carbon on Earth is indeed roughly fixed. The difference, as you point out is indeed its location. This carbon does also naturally shift slowly between atmospheric and deeply-sequestered sources. These facts are the crux of the argument about human impact on climate. Operating under the belief that atmospheric carbon is a key driver of mean global temperature, introducing non-atmospheric sources, like that which is locked up in coal, petroleum, limestone, &c is believed to raise the temperature. The key difference between humans and ants in this regard is that all of the ants’ carbon was recently removed from the atmosphere. When they die they simply re-introduce it into the atmosphere and other bits of the “surface-atmosphere” carbon cycle. Humans, on the other hand have been rapidly reintroducing sequestered carbon into the atmosphere. That’s why ants are not being blamed for climate change. (If this isn’t clear, I’m happy to address it in greater detail.) The reason volcanoes don’t typically get the blame is that the concentration of atmospheric carbon has been accelerating beyond its historical fluctuations since the beginning of the Industrial Revolution, while there does not seem to be any significant change in global change in volcanism.
The sun does provide most of the Earth’s energy, but a significant portion is also derived (or available) from radioactive materials. The Earth is “soft” in the middle in large part due to radioactive decay.
As for my thoughts on the subject, I perceive that the bulk of scientific opinion believes that global warming is real and that humans are to blame. The US National Academies (and many of their foreign counterparts), AAAS, AAG, and many other national scientific organizations support this claim. As much as many political figures would like to claim otherwise, there is still discourse on the subject. The American Society of Petroleum Geologists, for instance feels that the jury is still out. Modern science embraces debate in order to strengthen its conclusions or to find new ones. Has it “proved” that humans cause global warming? I think the answer to that question is a debate on positivism versus post-positivism.
That said, I’m willing to trust this assertion of so many professional scientists. After all, they’ve done right by me, for the most part.

David said...

PJ,
What I’m aiming for with the question of unexplained v. unexplainable is this: If science is exploring a topic but has not yet reached tenable conclusions, is this really failure? If science recognizes that it may have a better understanding of something in the future, and creates a system of active discourse, are its conclusions less reliable? Does science have to be able to prove something in the classical sense to draw any conclusions?

Chris McClure aka Panhandle Poet said...

e.r. In your opinion, if all industrial activity ceased and the human impact on the carbon cycle was exactly that of other living creatures (such as ants), would there be global warming? Where did deep sequestered carbon originate? Wasn't much of it, such as petroleum, at one time a part of the living biomass?

As for agriculture -- I don't foresee a significant reduction in capacity.

Do you anticipate a shrinking of the world population? If so, due to what causes? Will global warming and the consequent disruptions lead to increases in war, hunger, disease, etc.?

David said...

panhandle poet,
The answer to your question is that I think we need to make a distinction between those factors we do control and those we don’t. On the issue of human activity, I think that if humans stopped reintroducing carbon into the atmosphere, anthropogenic effects would only continue to accrue, briefly. Other factors affect the concentration of atmospheric carbon, but these factors seem to work on a much longer time scale than recent human activities. The kind of natural mechanisms that resulted in the formation of so many carbonate rocks and coal during the Carboniferous Period cannot be affected by current technology, nor should they be affected.
The deep-sequestered carbon was at one time part of the atmosphere and the biosphere. This carbon was cut-off from the biosphere-atmosphere carbon cycle by natural processes. Some studies suggest that temperatures were considerably warmer at the time when many coal beds were big, swampy forests full of weird animals, and the carbon within those forests was cycling through the atmosphere. That’s where part of the concern comes from.
Your population question speaks directly to a discussion from a while back, and to a future post. I think the question as you state it is missing one key element: the time table. In my unfounded opinion, the human population will eventually = 0. Too bad, thanks for playing. It’s happened to all kinds of successful species before. I don’t care to speculate at what point in the future that will be, nor what the end will look like. I think there will be a long, slow decline, punctuated by unpleasant events, but you can pick your favorite coup-de-grace: War, famine, ecological collapse, ice age, bionic space-zombies, &c. I don’t think there will be that many people left to experience it.
Likewise, I don’t see the global population shrinking any time in the near future. I’ve seen a number of population projections from reputable sources that get into the double-digit billions. If we’re right now willing to kill each other over oil, arable land, water, and what to call God, I think it could get a lot worse with so many more mouths to feed. Depletable resources are not a long-term solution to the escalating demands of a growing population.
That’s why I believe that now is the time to start building a sustainable lifestyle. A sustainable lifestyle doesn’t mean that we have to go back to browsing like monkeys and killing ungulates with stone-tipped spears, but it does mean learning to think like the people who did. We waste too much, and give very little thought to where our food and energy come from, or where our waste goes. More on that later, too.
We’ve gotten way off the positivism v. post-positivism / reliability of science discussion.

Pat Jenkins said...

erd would you not argue against a God because of it being unseen, or not physically identifiable. if science itself has not explained the "seen" then that which man has used as a tool for verification is unable to give explanation it has limitations. so by your own argument, science is thus flawed. now i am not of this mind set. science is limited by man's capacity of thought. to say things will remain unknown is not true because solutions will be discovered. on the flip side, some things will remain unresolved as well. i apologize i have gotten somewhat off the debate of your post, but none the less a discussion i have wanted to have with you. thank you for your patience.

Matthew said...

I enjoy watching debates such as these, it brings out the complexities of science, as well as how far we still have to go as a society.

The problem with Global Warming is that it is very difficult to be a laymen and understand the full issue. Global Warming comprises the most complex system - the Earth's climate, yet its effect is fairly simple (an average increase in the Earth's temperature). This simple effect then leads to a change in the complex system, and the game of atmospheric forcing take place (acidic oceans, stronger storms, prolonged drought, thermohaline shut down, and the like)

The different strings of theories and information that go into this is massive, which is why scientists have been working decades on understanding it, where as some in society make judgements based on a 3 minute news story or a brief speech by a stakeholder. The true issue at hand here is that

1) Due to the opposition of competing stakeholders in the causes of Global Warming (oil, coal, lumber, automobiles, freight, electric, and the multitudes of other production firms), this issue was thrown out of the hands of science and into the laps of interest groups. No matter what scientists say from here on out, and they have said plenty, there will still be a good portion of the U.S. population that doesn't want to believe it.

2) Due to the interest groups present and the possible future negative effects they will see, they went on the offensive. It has boiled down to a "presidential campaign". When one looks at the general election campaign, the most fraudulent, wrong, ridiculous, and misleading statements will be made to gain that edge, knowing fully well that any edge gained will bring even more to their side if they are still sitting on the fence. It is the classical game of manipulating those that do not or can not understand.

The science of global warming is not something that can be taught by casually reading a book on a Sunday afternoon. It takes proficient knowledge of atmospheric physics, partial differential equations, atmospheric chemistry, oceanography, climate science, geology, biology, and many more as well as the knowledge needed to learn these also. So by attacking the science, the interests groups know that they can gain an edge on the casual knowledge holder - and they have.

A clear example, is the increase in the use of statements such as, "global warming is a natural cycle tied to the sun" or variations thereof. These statements are made even though there are instruments that measure solar irradiance as well as sunspots and we know that output has not increased and we have been in a sunspot cycle that actually has a cooling effect on the Earth. These statements are made or passed onto media by these stakeholders to "muddle" the process. It is the same tactics used by the tobacco industry in decades passed and is very well documented.

Science has a deliberative and independent process. It has done its job of figuring out a problem (anthropogenic global warming) and by telling society "this is whats up" and we need to fix it. Unfortunately, due to special interest, the actual process of science has been tainted, by no fault of science itself - it is in mans nature to hold self interest higher than all.

People will continue to paint this as a political difference or one where science is wrong. Conclusively, all those that do so will watch human induced climate change occur, whether they like it or not. The main reference for those to learn about global warming should be scientists, it is not expected for all to know everything of the issue, but once science is labeled as "not true" because of the competing interests at hand, then society loses.

I have stopped arguing with people about global warming, except in specific instances, because the vehicles to drive the change needed are in place. Those that need to understand do to a point and those that are willing to turn there noses at it are on the out. Mainly though, this loss of wanting to explain is because you cannot have a scientific argument in the realm of politics.

ERD, thanks for the good questions and holding the debate - best that can be done at this point in regards to global warming is to hope that the political forces will catch up and soon. The lag of CO2 in the atmosphere ensures that global warming will continue non-stop for the next 100+years and with the oceans reaching their maximum CO2 holding point, the time for change was yesterday, not come 2009.

Oceanshaman said...

I really don't know . . . but my mind is clear . . . the sun feels warm on my face, the breeze is fragrant, and I stand ready to do the next right thing as it arises before me . . .

Clear mind, don't know . . .

Beginner's mind is a good thing to have . . .