A Catastrophe that Isn’t

The pitch is about as direct as you can imagine, the causal chain unambiguous and damning. There is, we are told, a place called the Marshall Islands, a collection of coral islets straddling the equator a few hundred miles northeast of Australia. A little slice of paradise, it is an idyllic place of waving palm trees, warm ocean breezes, and happy, innocent natives. And now it is is doomed, shortly to be inundated by rising waters, thanks to melting polar icecaps caused by global warming. Triggered, of course, by an  increasing amount of CO2 in the atmosphere. Which is caused by YOU, dear user of carbon-based fuels.

And that’s just the opening salvo. What follows is an epic guilt-fest with all the subtlety of a tire iron to the solar plexus. In tones by turns elegiac and insinuating, we are confronted with all that will be irretrievably lost when–not if–these islands are flooded. The implication is left hanging there, like a badge of shame: This is YOUR fault. Your gluttony, your greed, your shortsightedness are causing innocents to suffer. Nice going, First World.

If after reading the article your first inclination was to reach for a shovel, for to dig a hole, therein to crawl, you can hardly be faulted. This was precisely the intent. Indeed, in the face of such an obvious, monstrous crime it seems almost in poor taste to raise even a peep of protest. But even murderers get their day in court, and since an accusation has been leveled, it is only fair to respond to it with facts and reason, just as if a legal action had been brought against us. Does the accusation holds up to close analysis? Or does it evaporate like a rain puddle in the bright summer sun?

If you look at a map of the western part of the Pacific Ocean, you cannot help but notice how very many islands litter its watery vastness. There are thousands of them, scattered like stars across the night sky. Big ones, little ones, in-between ones. Of this collection, a hefty percentage are atolls, low-lying, ring-shaped coral islands enclosing a central lagoon, barely reaching above the waves. The Marshall Islands are of this type.

How improbable, you think, that there would be so many thousands of such islands, scattered all over the place, all lying right at sea level. What are the odds? And how unfortunate for their inhabitants, what with sea levels galloping upward, so we are told, about to erase a whole bunch of place names from the map.

But if you are a thinking person, it might occur to you to wonder how so many thousands of separate geographic entities could have independently come to be at exactly the same existential juncture, all lying precisely at sea level, presumably facing inundation, at the same moment in history. Had this happened by chance, it would be one hell of a coincidence. And if that seems like an awfully tall order to you, you are trending in the right direction.

In actuality, this is not a chance occurrence. Rather, this proliferation of like landforms is the end result of natural processes that have played out over countless millennia. And which will continue to play out far into the future. If the last six hundred million years or so of geologic history are any guide, that is.

The western rim of the Pacific Ocean is a geologically active region, with lots of tectonic plates moving every which way. There are many zones of tectonic convergence, in which adjacent plates move toward one another, with one typically sliding under the other. With tectonic convergence comes volcanic activity and mountain-building. The mountains thus built jut above the water, forming islands. The islands that comprise Japan, the Philippines, the Marianas, the Ryukus, and the Marshall Islands were all formed by this process.

But as with most things natural, a life cycle appertains. From the first moments of their existence these mountainous islands are subject to relentless erosion, which works to wear them down. At the same time, as the forces that built these mountains subside, they begin to sink naturally under their own weight, and even without erosion most would eventually drop into the sea.

The sunlit zone of warm, tropical waters teems with all manner of corals, symbiotic organisms that form large colonies–“reefs”–that cover every square meter of habitable sea bottom. Corals have the very useful ability to secrete calcium carbonate, also known as limestone. Each individual coral polyp constructs its own protective enclosure from this durable material. When the individual coral dies, its enclosure remains, to form the foundation for the next generation.

Corals tend to be very prolific, and spread rapidly in all directions, including upward. Corals will grow right up to the surface, into the tidal zone, and can even survive brief exposure to air. Under favorable conditions, certain common corals may generate a foot or more of vertical growth in a year, blazing fast in geologic terms.

From the surf zone down to a depth of 70 meters or so, the flanks of every tropical island are covered with a fringe of living coral. As time passes and the mountain-islands sink into the sea, the coral builds continuously upward and inward, stopping only when it reaches the atmosphere. Eventually, the coral covers the mountaintop when finally it slips underwater. But even as its foundation descends into the depths, the coral continues growing endlessly upward, piling up layer upon innumerable layer. The end result is a coral atoll, whose ring-shaped form echoes the reef that once fringed the submerged slopes of the mountain.

Pick any atoll and drill into it and you are likely to find thousands of meters of fossilized corals, representing millions of years of history, layered atop a submerged peak. The part above water, what we call an island, is made of ground-up pieces of reef, piled up by waves and currents and reworked by the wind, generally topping out no more than a meter or two above sea level. The atoll is the end stage of a natural process, and will persist indefinitely as long as the corals that comprise it continue to grow.

Only when the water turns too cold to support it does the coral stop growing. Which happens regularly, geologically speaking, as most of the tectonic plates that make up the Pacific seafloor are moving generally northward at a rate of a few centimeters per year. Between latitude 25 degrees north and 25 south, you find thousands of living atolls, flourishing in the relative warmth of tropical waters. Outside that zone, you find many seamounts, submerged mountains capped by dead coral colonies that succumbed when their tectonic plates carried them into chilly waters.

But unless and until that happens, coral will naturally replenish itself indefinitely. So in reality all the guilt-tripping is for naught. We needn’t worry about the Marshall Islands, the Marquesas, the Maldives, or any of the thousands of other tropical isles supposedly facing imminent inundation. Not for the foreseeable future anyway. These island-nations are not in any way threatened by seas that continue to rise at the very modest rate of 7 or 8 or 10 inches per century because the coral of which they are formed can grow much faster than that, and will easily keep pace. Undoubtedly, these places can and will on occasion experience flooding, though, as would any low-lying landform sitting in the middle of an ocean periodically swept by strong storms and large waves.

The mass media is perennially atwitter with alarming bulletins about this or that impending catastrophe. And almost always, the promised apocalypse fails to materialize. This time will be no different. You’d think that we would learn after so many false alarms. Yet somehow we fall for it every time.

There is a common thread that runs though each of these stories. Someone takes a little bit of data, usually collected over a very short term, and divines a trend. This trend is then projected unrealistically far into the future, as though it existed in a vacuum, unaffected by any other factors. Using such simplistic logic, we can confidently predict that there will upwards of 500 trillion humans on this planet a thousand years from now, based on the current rate of population growth. This is an obviously absurd projection. Yet there it is, in black and white. Numbers don’t lie.

I find it noteworthy that CNN, supposedly an objective news organization, seems to have no qualms about hosting a story that is so obviously a work of advocacy journalism. And it is, apparently, of no concern that this high-profile piece is based on sloppy science, is factually unsound, emotionally manipulative, and intentionally misleading. All that matters is that it generates lots of buzz, hence ad dollars. Comments for the story have been disabled, so we can assume that critiques are unwelcome. Which is understandable, because as any propagandist can tell you: You should never, ever let pesky old facts get in the way of a good narrative.

 

 

 

© 2016 By Scott P. Snell

Right to reuse is freely granted with proper attribution.

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