By SCOTT DANIELSON
The dire warnings are starting to pile up faster and faster, but we are still mining fossil fuels out of the earth as fast as humanly possible and torching most of them. What about my children? And their children? Will they need petroleum? Biological diversity? Clean air and water? Of course they will. Is it really our right to empty the coffers of the earth in a few generations?
In this decade we will pass the oil peak. From then on, forever, there will less oil pumped worldwide. What is left will be more and more difficult to extract. Humans will have to adapt to this fact, and Americans more than anyone else because we are 5 percent of the world's population, but we cause 25 percent of the world's carbon dioxide emissions.
We now know that our feeding frenzy on this treasure trove of energy will have a terrible backlash—global warming. An insidious, invisible byproduct of burning fossil fuels is carbon dioxide. The level of that gas in the atmosphere has increased more than 30 percent since the industrial revolution began. By examining air bubbles trapped for millennia in Greenland ice, scientists can show that global temperature is linked to the carbon dioxide level in the atmosphere. We have now reached the highest level of atmospheric carbon dioxide in the last 650,000 years, and that level is accelerating. It takes decades for the carbon blanket to raise the average temperature of the entire Earth.
However, once it starts, it will be an inexorable change. Picture all of the people in the industrialized regions of the planet pulling on a gigantic freight train (the Earth's climate). We thought the climate system had great stability, as if the train was safely in a large valley. We were taught that any excess of carbon dioxide would simply be absorbed by bountiful vegetation.
No such luck.
In fact, the freight train has been perched on top of a hill for thousands of years. That gargantuan train is now starting to move off the hill and some of the people who have been pulling are glancing behind them, wondering if it will be possible to put on the brakes. Since carbon dioxide stays in the atmosphere for more than 100 years, putting on the brakes is not a simple matter. It will require a lot of willpower, both by individuals and by governments.
Scientists are finding evidence of rapid climate change further back in the geologic record. They're changes that resulted in wholesale extinction. In fact, many scientists predict that by the end of this century, one-third to one-half of all the species on the Earth will become extinct. The Arctic ice cap may disappear entirely by 2050.
Three weeks ago, NASA released a study revealing that between 2004 and 2005, the perennial sea ice in the Arctic diminished by 14 percent. Other studies show that many areas of permafrost in the Arctic regions are thawing. This is permafrost that has been frozen since the last ice age. Nine of the top 10 warmest years globally have occurred in the last 10 years. This is from records maintained by the National Climate Data Center since 1880.
The real concern is that we are approaching, if we have not already passed, a tipping point, a point where that symbolic train reaches a downhill slope where no amount of human intervention will be able to stop the runaway climate change.
There are, namely, a number of "positive feedback loops" that can have extremely negative effects. For instance, when the Arctic ice cap melts, the reflective ice surface will be replaced by dark seawater, which absorbs even more heat, which melts more ice. As permafrost thaws, vast amounts of trapped carbon dioxide will be released. And as the ocean warms, methane (an even more powerful greenhouse gas) will bubble up from the depths.
There is no way to end this essay on a glib note. This is shaping up to be the greatest struggle that mankind has ever faced. We may be causing, collectively, the sixth mass extinction since life emerged on Earth 535 million years ago.
Park your car. Take the bus. Carpool. Or even better, ride a bike. Lower your carbon footprint. Try to influence politicians to support renewable energy sources—solar, wind, geothermal—and more stringent regulations on fuel efficiency.
Do it now, not later.
Scott Danielson is a resident of Ketchum.
