My college geology class was taught by Stephen Jay Gould, an evolutionary biologist who loved fossils and the lost worlds they evoked. He was obsessed by the variety of the Earth's species. He said they showed the near-infinite number of forms life could take, given 1 billion years, continuous solar energy and a small, wet planet.
Gould's lectures demonstrated how the Earth's climate goes through periodic phase changes from really warm (most of geological history) to cool with ice caps (now). Tiny changes in the Earth's orbit, atmosphere and surface have, at separate times in the deep past, caused redwood forests to grow on Ellesmere Island--west of Greenland--and oceans to freeze all the way to the equator.
That geology class, with its emphasis on physical cause and effect, made it easy to believe in human-caused climate change.
Take a planet in its cool phase. Cut down its rainforests, cover large areas with concrete and asphalt, dump billions of tons of carbon dioxide and methane into its atmosphere, stain its ice caps with coal smoke and you've begun the phase change back to a really warm planet.
There's no stopping it. Feedback loops come into play. Siberia and Alaska and northern Canada become giant methane and carbon dioxide generators. Ashes from burning forests cover more glaciers and icecaps. Open water in the Arctic Ocean absorbs far more sunlight than ice does, which creates more open water, which absorbs more sunlight. Jet stream anomalies create droughts and floods where farmers used to grow crops. Tundra dries out. Warming oceans stop absorbing carbon dioxide. Deserts grow, fire by fire, dust storm by dust storm. You can't get back to the soft green valleys and snow-covered mountains.
Not much that is humanly good will come of all this, except for the fact that climate-change deniers will have plenty of sand to hide their heads in. Beyond that, I'm unwilling to predict. As many a soothsayer has discovered, it's unwise to get specific about the future.
Years back, I saw predictions of a reduction of human numbers from 7 billion to 500 million by 2100, mostly as a result of running out of fossil fuels. Then the same people changed their predictions to human extinction by 2050, mostly because we're not going to run out of fossil fuels, and when we burn through what we've got, the Earth will look like Venus.
Contradictions aside, that's straying too far from the data. The future contains too many variables and out-and-out surprises. It's much more useful to look clearly at the world and make an honest attempt to predict the present.
Here's what I imagine historians of 2100 will write about the year 2013, even if they are writing with the ends of charred sticks on torch-lit subway tunnel walls:
• When human population reached 7 billion, people realized that the planet had exceeded its long-term carrying capacity. What they didn't realize is that it had also exceeded its short-term carrying capacity. Fresh water, in particular, became a limited resource, causing mass migrations and civil wars.
• The elected leaders of the world's democracies gave up working for the long-term well-being of their peoples, and started directing public funds toward the immediate benefit of the three Fs: families, friends and faiths.
• Capitalism depended on continued expansion for its survival. When real economic activity ran up against resource limits, economic policies in developed countries devolved to the other three Fs: funny money, funny credit and funny financial occupations. This devolution allowed economies to preserve their forms if not their functions.
• Young people in developed countries opted for anesthesia via video games and social networks and other forms of virtual reality. As a group, they constituted an electronic lumpenproletariat, a large population of serf-like sub-adults that passively sustained the status quo despite the efforts of the few old Boomers who could still remember the concept of social justice.
• Millions were incarcerated because the incarceration industry had grown large enough to dictate laws that criminalized almost everybody. Millions of others were engaged in wars or preparation for wars, because the arms industry had grown large enough to militarize almost everybody not already in jail.
• Economic conferences were held at resorts like Davos, Sun Valley and Aspen, where movers-and-shakers were insulated from the effects of their policies by mountains, recreational infrastructures, heavy security and the flattery of sycophants. No wonder they grew ever less responsive to the life-and-death problems of their constituents and employees.
That's what predicting the present looks like. Checking its accuracy depends less on staring at a screen and more on looking out the window.
Gould has been extinct for 11 years. His was a voice of reason and justice and sanity in a world that doesn't have enough of any of them.
What I remember best about his class are his lectures on dinosaurs, where he delighted us with critiques of giant-animal movies. King Kong and Godzilla, he said, would die of metabolic-induced heat stroke before they wrecked a single city, and Mothra wouldn't get off the ground unless the atmosphere had the density of water. Dinosaurs had reached the size limit for land and air animals, and the blue whale could exist only because the cold ocean siphoned away the excess heat.
I've wondered what Gould, as an evolutionary biologist, would think of humanity these days--if he would see it as a loose grouping of 7 billion individuals or as the soon-to-be-obsolete feedstock for a bloated civilization whose out-of-control metabolism is frying its nerves and congealing its little brain.