Isn't Weather part of Nature, too?

kw: opinion, environmentalism, ecology

The other day, on a PBS broadcast, I heard the phrase, "...a fragile ecology at the mercy of the world's weather..." I immediately thought, "What balderdash! The weather is part of the ecology."

When I was a graduate student of Geological Engineering in Rapid City, SD, I often went with fellow students to see their project areas, as many of them came to mine. One area was an alluvial fan below a steep canyon south of Sturgis, SD (an alluvial fan is a sloping plain formed of the debris of a river's erosion of young mountains. The Black Hills are part of the Rocky Mountains, a relatively young mountain chain).

The fan had a great scattering of large boulders, some as large as a minivan. My friend had mapped the locations of all the boulders, from three feet in diameter up, and measured the size of the lichen spots on them. From the known growth rates of lichens, he was able to determine that there had been more than ten flooding events in the past 5,000 years, or about one per 500 years, with sufficient force to move stones weighing many tons as far as two miles from the canyon mouth. Some older stones showed signs of having been uprooted and moved by later floods, from where an earlier flood had left them.

The current climate that we call an Ice Age Interglacial period has been relatively stable for about 11,500 years. But by "relatively stable," we must include times much colder than today, even colder than the "little ice age" of the 1400s-1800s, and periods of warming quite a bit beyond our expectations of the next hundred years of "global warming." Yes, I do believe the current warming is in large part caused by our burning of fossil fuels, but it is certainly not unusual compared to the excursions of the past ten millenia or so.

The various ecological zones of each continent contain assemblages of plants and animals that have existed over that span of time. When things were cooler, those that could, moved south or downhill, and when warmer, north or uphill. The rest adapted without migration, or went extinct. Those today existing are those that adapted, with or without migration.

The idea that a 100-year flood, a 100-year drought, or a 100-year "disaster" of any kind is unprecedented is a truly blind viewpoint. My friend noted that he couldn't tell yet which of the floods whose debris he had mapped had been the worst. Whichever it was, it was the 10,000-year flood, and didn't make great numbers of things go extinct.

We still have a lot to learn about the resilience of ecological systems. Our lifetime is too short to provide a useful baseline. Even all of written history encompasses only half the current Interglacial. Until environmentalists become astute students of history, we'll go from panic to panic, for no good reason. A pity...