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The mountains and the sea, Part 1

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Rummaging through my closet, I came upon my old professor hat.  Thought I’d put it on, and write a bit about sea level.

If you’re a hiker, you’re familiar with those USGS topo sheets showing, among other things, terrain relief.  You probably also know those numbers you see on the elevation lines are all measurements of the vertical distance to sea level.  Even if you’re not into hiking, you might know the elevation of some mountain, or the highest point in your state, or the levee down by the river; same thing for them, measured above sea level.

You probably also know that the sea level is rising.  What does that do to all those numbers?

Well, nothing, actually.

It might seem that the level of the sea used to be constant, and any change is pretty recent, but there have always been fluctuations, both on a local and a global scale.

Think about something as seemingly simple as determining sea level at any given point on a shoreline.  Do you measure it during high tide or low?  Full moon or new?  What about those little ripples  of waves lapping the shore; is your measurement going to be taken at the maximum encroachment or the minimum?

Okay, fine, you say, measure all those points and use the average.  That, in fact, was originally what was done, which is why the official elevation was always given as distance above mean sea level.  Unfortunately, that doesn’t fix things.  Because, you see, you have to ask yourself, mean sea level exactly where?  The solution was to take means at various points, and average those, and so on.

What developed was a convention in which a statistical mean was taken as sea level, which didn’t correspond to actual sea level anywhere in particular.  At this point, sea level was already an abstraction, but some respect was still given to the original concept, and means were kept as close as possible to actual sea levels.  But it turned out that if you used a global mean, the numbers were too far off.  In the end, we got elevations taken with respect to various regional reference points, or datums, around the world: the North American datum, the European datum, and so on.

Confused?  How can sea level differ so much around the world?

First of all, the earth is not a sphere; it’s more like a lumpy egg.  As a result, early suggestions to use the center of the earth as a reference were useless.  Furthermore, water is not even level with respect to local elevations.  Lake Huron, for example, is 5 centimeters higher at the south end than at the north end.  This is partly due to the direction of water flow, but also in the difference in composition of what’s under it.  The iron-rich substrates in the north are denser, and therefore exert a greater gravitational pull.  These effects are compounded globally.

The result is the so-called equipotential system of sea level.  Rather than using the physical measurement of the distance from a point above another point, mean sea level is now defined as an imaginary surface on which every point measures the same gravitational pull.  The only concession to the actual level of the sea is in the name.

Of course, that used to be a very hard thing to measure.  Thank goodness for GPS satellites.

(to be continued)

Time and the swelling tide

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I was just out walking in the town I live in.  An unseasonably nice day, warm and breezy, like the best days of early fall.  Then it hit me: my generation may very well be the last to experience habitable climates on most of Earth.

It is almost certainly too late to adopt enough changes to avoid disaster.  As for our social preoccupations, they are vexing, for sure, but not nearly on an order of magnitude comparable to environmental issues.  No matter how our current crises play out, how sordid or how sublime our responses to the xenophobia raging across the planet, it will all take its place in history, alongside all the ages, dark, golden, or forgotten.

If there still is history.  If the effluent we keep pumping into the air leaves us with a future, let alone history.

In a way, it’s a self-correcting problem.  Either we correct our course, which seems increasingly unlikely, or we render our planet inhospitable.  In either case, our cultures will change, and our sheer numbers will decrease, in the former case by intelligent design, in the latter by brute force.  The earth will return to its inanthropic cycles, none the worse for wear, to whatever state counts as normal.

We are far too young a species to grasp what that is.  Earth has passed through phases as diverse as completely covered with ice, an atmosphere poisonous to virtually any life, and desiccation more severe and universal than anything since we crawled out from our ancestral apes into the brave new world.  Through most of it, life had yet to occur, much less evolve, and even when it had, it clung tenuously to existence.  At least five times since it’s emergence, life has been almost wiped out.  Even our own species was squeezed through a fine and narrow filter some 60,000 years ago, when genetics point to a breeding population of Homo sapiens of less than 2,000.  Some scholars speculate that it was during this period that our evolving intelligence was given a swift kick to accelerate it, in response to the demographic crisis.

Given how that is turning out, I’m not very optimistic.  I hope I’m wrong.

Notice to Consumers

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It has come to our attention that some of you have been seen engaging in activities that have little or nothing to do with consuming.  This, of course, must stop, as it jeopardizes the entire consummation system.  In the 19th century, enthusiasm for consuming was so robust that people were even reported to have died from consumption.  Are we to fail such a heritage?

Even the French have surpassed us.  There is a soup there called consommé which is quite widely used in cooking, even though, judging from the name, it has clearly already been consumed before.  Surely we can do as well or better.

If the general population fails to improve by next Tuesday, all businesses in the US will be forced to not only become French, but to move all operations involving wage earners to an impoverished country … what?  Oh, never mind.  Become French, then.

Some rank observations

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Why is the lowest rank in the army, which affords its holder no privacy whatsoever, called private? The corporal, at least, seems reasonably preoccupied with bodies. But what is a sergeant? Someone bedecked in serge? A warrant officer, I suppose, is the person in the office which processes warrants, but you’d never know it from their duties.

I get lieutenant; he’s a tenant in a place, and the captain is surely the head man. But if he’s the head man, why are there ranks above him?

To be sure, in the navy, there are fewer ranks above captain, but that’s the navy, always going their own way, doubtless from spending so much time on the bounding main, far from civilization. A friend, and ex-submariner, once told me they left port with 150 sailors, and returned with 75 couples. I guess that explains the ranks of mates; very chummy, these sailors. Perhaps it also explains admirals, presumably persons most to be admired. As for the rest of them (only some of whom are able bodied), they are seamen. Very clear and to the point, much like the airmen in the … air force. Someday soon these basic descriptive ranks will have to be modified to reflect the modern military: seapersons and airpersons.

But above the captain in the army there are majors and colonels before you even get to the highest ranks. Majors, I believe, are self-explanatory, but what on earth is a colonel? Something to do with columns? If so, why is he allowed to lord it over the head man?

The generals, those with the highest ranks, presumably do not have any specific duties, like the lower ranks, with the exception of the lowest of them, the brigadier, who mucks about with brigades. Yet they feel compelled to recapitulate practically the entire officer rank system among themselves, from lieutenant to major, skipping colonels, perhaps because generals get nowhere near any columns except during parades.

Don’t get me started on unit designations; that’s something only a very admiral general could explain.

The making of a curmudgeon

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I have often thought that I’m regarded by my friends with a mixture of disbelief, alarm, and chagrin. I seem inexorably drawn to insert my opinion into any and all discussions I stumble upon. I mean well, but I’m afraid I offend too often and too blithely. I don’t regret my propensity to skepticism, but I often regret having offended someone I respect.

I don’t think this is a learned response. As early as the first grade, I got into trouble with the nuns at my school for spreading the word around the playground that there was no Santa Claus. I was dumbfounded. Hadn’t they been teaching us just that day what a terrible thing it is to lie? Apparently, some of my classmates had gone to them in tears, asking if it was true. I imagine the nuns consoled them, “There, there, of course there is a Santa, and don’t let anyone tell you otherwise!”

I knew better; I had the news on the highest authority: my older brothers. Is it any wonder I started questioning everything else the nuns told me?

I’m a born outsider, literally. I was born in a refugee camp, and have never felt completely in my element, and I suppose this is a major factor in the way I relate to other people. It gives me a kind of distance that encourages my behavior.

To make matters worse, my father was an engineer by training, and a scientist by temperament. Instead of golf or bowling, he relaxed by reading science fiction and doing math problems. The first requisite of science is skepticism, and I learned it well. Too well.

He was also a deeply religious man, a Catholic who gathered the family around the radio to listen to and pray the rosary at the regularly appointed hours on Catholic radio. Naturally, when I got old enough to enter my normal rebellious years, I jumped on this contradiction in his example.

I did 12 years in parochial schools.  Once, in my sophomore year, I flunked religion class, for the sin of asking too strenuously how the Holy Trinity wasn’t just semantic trickery.  A certain native pig-headedness embroiders my skepticism, it seems.  My father was mortified.  He told me that he would rather I flunked everything else, but aced religion.  I briefly considered testing this theory, before coming to my senses; I had no desire to be sent off to a monastery.

Apparently, there were two rules:

  • Question everything
  • Accept Catholic dogma blindly

I could have chosen either of them to avoid the contradiction. For a number of reasons, I went with the first. Dogma is surrounded by walls; walls invariably yield to skepticism. And so, to this day, I am cursed with this compulsion to question everything. That’s not to say I don’t have my own blind spots, my contradictions; I would tell you what they are, but, of course, I don’t know, and wouldn’t recognize them if they jumped up and bit me on the nether regions.

Fortunately for me, my friends generally do not hesitate to help me out.