The Greening of the Land

Michael – Thursday.  

I don’t want this to be a rant. I think those should be saved for Facebook. And I’ve written about climate change before, but things have become worse since then so please bear with me.

Last week it was so chilly in Florida that iguanas were falling out of trees because it was too cold for their blood to keep moving properly. (Fortunately they often recover when it warms up.) The east coast was frozen—or much colder than that—and swamped in feet of snow. JFK was totally disrupted, as Annamaria discovered when she landed there.  Boston was flooded. I guess it was even too cold for the president to play golf. Another bad week for him. He did, however, quip that ‘we could do with more of that global warming around here.’

Europe, too, has suffered extreme cold weather, flight disruptions, and the like.  Meanwhile, last summer heat waves, droughts, and fires swept vulnerable areas.  Cape Town will run out of water in a few months.

Clearly, these scientist-types are way off the mark. Global warming? With record cold temperatures? Ridiculous. So what on earth is going on?

Greenland is sometimes put forward as an example of why temperatures come and go, but the planet goes on much same. When Erik the Red arrived there about a thousand years ago (from Iceland at the time but he wasn't too popular there), he decided to start a colony. The land was verdant and welcoming, and he named it Greenland. So there. A thousand years ago, Greenland was much warmer and more attractive. What’s a thousand years in geological time?  

Unfortunately, it’s a good story but it’s not true. First, recall that Erik was a Viking who had been exiled from Iceland. I love the people of Iceland and their dramatic country, but their ancestors probably had a rather different interpretation of “green” from the people of the Amazon rain forest.  The game is given away by this quote from The Saga of Erik the Red: "In the summer, Erik left to settle in the country he had found, which he called Greenland, as he said people would be attracted there if it had a favorable name." Greenland today probably has less ice cover than it’s had in its 4,000 years of human settlement. And the rich glacial soil does, indeed, produce a green strip around the coast in summer (as it always has).

Weather is an extremely complex non-linear system and has chaotic behavior (in the math sense as well as the real world sense). In fact chaotic systems were first discovered by Edward Lorenz when he tried to work on a simple model for weather prediction. Some such systems have a variety of attractors that are called 'locally stable'. What this means is that if the weather behaves in a certain general way, it will probably continue to do that with some perturbations. But if you kick it too far from that 'certain general way', it will move to somewhere rather different and the process of moving there will be largely unpredictable. Thus you expect higher than usual temperatures, lower than usual temperatures, vicious storms, floods, droughts, whatever. Does this ring any bells?

In other words, what we are seeing now is exactly what the scientist-types predicted all along. For this very reason, the term “climate change” was coined—not because it denied global warming, but because it’s the change process that we will be experiencing in our lifetimes. But over time the system will move to another locally stable state where the temperatures will be higher. For some. If the jet stream settles significantly south, a new ice age will hit northern Europe. And Southern Africa will become a desert.

Going back to Greenland, the ice sheet is enormous, covering an area of more than half a million square miles and a depth of two to three miles. It’s a huge reservoir of fresh water, and it’s slowly melting. It is also a record of the past, literally frozen in time. It consists of layers of compressed snow going back more than 100,000 years. Scientists have drilled into it several miles deep in order to explore, among other things, the record of past temperatures.

In 2013 in an article in Nature a large research project reported that, indeed, Greenland had been warm before—some 118,000 years ago the temperature was eight degrees centigrade higher than it is today. (Well before Erik was even a twinkle in his mother's eye.) If that happens again for a prolonged period, the world’s seas will rise about 20 feet, flooding every coastal city. Never mind what will be happening in the Arctic and Antarctica. Most climate change models put that temperature increase within a few hundred years, but, since it's a chaotic system, it could be a lot longer or a lot quicker.

Oh well. Let’s not worry. Our children’s children can deal with it, right?