Thursday, May 31, 2012

AW #46: Geology, Life and Civilization- Chaotic Feedback

Cat at Knowledge Flocs is hosting this month's Accretionary Wedge with a topic that looks relatively simple and straightforward, unless it's a topic you've spent some serious time contemplating, as I have. To wit: "How has life or civilisation been affected by geology or how has geology been affected by life?" With the provision that I'm going to change the last "or" to "and," here are some conclusions I've come to over the years, with a prefatory tangent.

The concept of "chaos," as it was developed during the late 70's and early 80's, and coming to public attention particularly in the late 80's, is at once fairly simple and straight-forward, but at the same time, I think, widely misunderstood. The important idea is that arbitrarily small differences in starting conditions of a particular system can lead to arbitrarily large differences in outcomes given enough time or iterations of the equations that describe said system. The iconic images illustrative of the concept, those of the Mandelbrot set, are the result of iterating a single simple equation (albeit one using complex numbers) to determine which starting conditions do not result in tending toward infinity after approaching infinite reiterations. Even very simple systems can exhibit chaotic behaviors, such as one of the ones first recognized as such, the Lorenz attractor. Note that while this is described as "a system of three ordinary differential equations," it isn't necessary to think of them as differential equations; one could consider them as a set of iterated steps:
  • Using current x, y, z positions, calculate new velocities (dx/dt, dy/dt, dz/dt).
  • Add new velocities to current positions to get new positions, and go back to beginning to reiterate.
Simple, huh?

The point is, the earth's components/systems, which because of my background, I tend to compartmentalize as geosphere [solid], hydrosphere [liquid], atmosphere [gaseous], and biosphere [living], with additional influences from the environment in which it rests ["space"], are each, in and of themselves extremely complex chaotic systems, involving huge numbers of variables. The above two examples are chosen to illustrate the simplicity of systems in which chaos can arise. Any one of earth's component systems is many magnitudes more complex than these... and when one tries to integrate all five into a unitary "Earth System..." well, speaking for myself, my mind just boggles. It's not a "complete fail;" I can dimly perceive patterns, trends, I can sensibly speculate, but I feel I'm relying more on constrained imagination than data, logic, and reason. My confidence in the "conclusions" I reach is best described as "minimal."

The focus of much popular science in the public mind is on things that are simply not understood by the vast majority of us (and yes, I intentionally include myself). Ask a group of random (or selected- I doubt it makes much difference) people, "Based on what you know and read, what are the most important questions science is trying to address?" I would be willing to wager responses that come up most frequently would include:
  • What is the nature of the Higgs Boson? Does it exist?
  • What is Dark Matter?
  • What is Dark Energy? Does it exist?
  • What sources of non-fossil energy are practical, and how can we transition to them with minimum effort?
  • Does life exist elsewhere in the cosmos? Where might it?
  • What is the cure for cancer/HIV/the common cold (Yes, I understand that the first and last are nonsensical, the second might too, and that's kind of the point.)
And while you might occasionally get something along the lines of "What are the consequences of global warming?," or "Is global warming real?," I'd also be willing to wager that an answer you would almost never get is along the lines of, "How can we better understand the dynamics of the total earth system, and make better predictions of the consequences of our interactions with it, in order to maintain our civilization without putting ourselves and important aspects of the earth at risk?"

And I ask, in all sobriety, "Can there be a more important question than that?"

The focus here is intended to be geology, but if you've read this blog for any length of time, you know I tend to flog the point that the solid earth is, directly or indirectly, the source of almost every single resource we use. I was going to say, "excluding air," but realized even that is in part a result of solid earth interactions with the biosphere. (Plants require phosphorus, potassium and magnesium, as well as a variety of micro-nutrients, that are available over the long term only from the solid earth.) I see no real point in beating on that theme again.

However, for those a little newer to OTI, here are a couple of older pieces that address this month's theme. The first, "Geo-Biz," focuses on some geology/economics news over a period of just a few days- and those few days were by no means atypical. Keep in mind "money" is at best a symbol of value, at worst an illusion. The real issue is the central consequence of being a living organism: the necessity to acquire resources. Economics is the study of how we as a species and a culture exchange resources we have in excess for those of which we are experiencing a deficit, with some other entity for which/whom the opposite is the case. Money is merely a consensual illusion that facilitates such exchanges.

The second, "Unanswered Questions," considers one aspect of a question that fascinates me deeply, and has for many years: "How has the presence and ongoing evolution of life influenced the overall evolution of the planet?" Specifically, the question I address is "how would the earth be different if life had never existed on it?" Spoiler: my conclusion is that for all practical purposes, it would be completely unrecognizable.

To end on an optimistic note, there are uncountable numbers of people working to make sure that we as a civilization continue to acquire the resources we need, and similarly uncountable numbers trying to assess, predict and avoid chances of environmental problems, disasters, and catastrophes. In other words, the scientific question I regard as most important is being addressed. I'll grant we're a long way from definitive answers on many important aspects of that question, and further still from integrating component answers into a broad understanding of "the Earth System," but the lack of discussion in most sources does not mean no one is working on it. Millions are. Many of these are scientists, many are not. Of the scientists, many are geologists. Many are computer scientists, chemists, atmospheric scientists, climatologists, astronomers or physicists in other sub-disciplines, biologists, and so on. But it bothers me, as a matter of pride, as a matter of pragmatism, and as a concern for the future, that the media, and as a result, the general public, is essentially blind to the fact of how fundamentally civilization is grounded (pun intended) in understanding, and understanding how to responsibly use, the solid earth.

No comments: