Dear Ones --
A year to the day. Exactly. That's admittedly a long time off between blog postings.
And of course, much has gone on since then. We've started a financial recovery, but the coming commercial mortgage crisis looms. We've endured a winter of record snowfalls, had abnormally high-temperature early April, Tennessee just had record-breaking rains and lost lives to flooding, and we're now in a somewhat more typical and stable weather pattern - meaning progressive fronts and rains, but in a steady and "normal" manner.
And of course, in the past few months, we've had multiple earthquakes, the Iceland volcano (still erupting), and now - contributing man-made environment stress - the oil spill off the Gulf Coast (still gushing).
By themselves, no one particular event - no matter how traumatic - indicates a world-wide crisis or significant shift. It is when we take these as a whole that complex trends emerge. Specifically, we are looking at the possible interactions between events, and event trends.
Interactions that will be highly nonlinear. This means, predicting outcomes will be much more difficult.
We begin with assessing just one contributing factor; earthquakes.
Using data provided by the multiple earthquakes, we don't - on simple visual inspection - see much of a trend increase with data gathered over this past decade.
Some authors present evidence for a significant increase in earthquake frequency; one that goes well beyond the increased world-wide availability of seismograph recording.
Fred Tasker gives a more conservative view, in
Does this mean earthquake frequency is increasing?. He notes, quoting respected geologists, two important points:
(1) Earthquake impacts are a function of not only magnitude, but also the geological substrate in which they occur; e.g., poorly consolidated sedimentary soil fares less well than other types, and
(2) We should not take earthquakes along one fault line as indicative of likely earthquake activity along other major fault lines.
Many volcanoes, like earthquakes, occur on earth's fault lines - the areas where tectonic plates interact.
(More to come ...)
What is interesting here (and perhaps essential to our futures) is that we have the possibility of nonlinear systems evolution. This means that we can't predict what will happen with simple, linear "rate increase" equations.
Look for good reference materials on my website; look for frequent updates!
No comments:
Post a Comment