New epoch proposed -- the Anthropocene

ABC News: We humans are having such a dramatic impact on our planet that some leading scientists think the current era needs a new name. We're no longer in the Holocene epoch, they say. We're now well into what they are calling the Anthropocene.

This planet is being changed by human activities in ways that will continue to alter Earth for millions of years. The most obvious example is global climate change precipitated by the release of greenhouse gases from fossil fuels, but there are many more, some so obvious it's hard to think of them as insidious threats to our environment.

But they are indeed, according to the leader of the Anthropocene movement, Nobel laureate Paul J. Crutzen, who is said to have coined the word during a science meeting in 2000. Crutzen, former chief of atmospheric chemistry at the Max-Planck-Institute in Germany and now a part-time professor at the Scripps Institution of Oceanography in San Diego, is out with a new paper that leads off with a provocative question: "Are Humans Now Overwhelming the Great Forces of Nature?" The paper, published by the Royal Swedish Academy of Sciences in the current issue of the journal Ambio, begins with this warning:

"Global warming and many other human-driven changes to the environment are raising concerns about the future of Earth's environment and it's ability to provide the services required to maintain viable human civilizations. The consequences of this unintended experiment of humankind on its own life support system are hotly debated, but worst-case scenarios paint a gloomy picture for the future of contemporary societies."

Pretty scary stuff, but Crutzen and his co-authors have done their homework. In fact, they argue that about the only thing that might head off a global human catastrophe is some other catastrophe, like "a meteorite impact, a world war or a pandemic." Here are just a few of their points, in their own words:

• Earth is rapidly moving into a less biologically diverse, less forested, much warmer and probably wetter and stormier state.
• Between 1800 and 2000 population grew more than sixfold, the global economy about 50-fold, and energy use about 40-fold. (Population is expected to reach 10 billion in this century.)
• Energy use grew 16-fold just during the 20th century, causing 160 million tons of atmospheric sulphur dioxide emissions per year. The number of motor vehicles increased dramatically from about 40 million at the end of World War II to nearly 700 million by 1996. (And according to other studies, all those vehicles are owned by just 15 percent of the world's population.)
• About 30 percent to 50 percent of the planet's land surface is exploited by humans. Tropical rain forests are disappearing at a fast pace, releasing carbon dioxide and strongly increasing species extinction.
• So far, these effects have largely been caused by only 25 percent of the world population.

..They call the modern period the Great Acceleration of the Anthropocene, when humans began to overwhelm their planet. In their own words:

"The Great Acceleration is reaching criticality. Enormous, immediate challenges confront humanity over the next few decades as it attempts to pass through a bottleneck of continued population growth, excessive resources use, and environmental deterioration. In most parts of the world the demand for fossil fuels overwhelms the desire to significantly reduce greenhouse gas emissions.

"About 60 percent of ecosystem services are already degraded and will continue to degrade further unless significant social changes in values and management occur. There is also evidence for radically different directions built around innovative, knowledge-based solutions. Whatever unfolds, the next few decades will surely be a tipping point in the evolution of the Anthropocene."

Those last couple of sentences are among the few encouraging words in their paper. Maybe we don't have to stumble down this path forever. But given the vast gaps between the haves and the have-nots, the relentless reach for a higher standard of living, the exploding need for more energy at seemingly any cost, it's hard to be optimistic.

As they note in their paper, "To develop a universally accepted strategy to ensure the sustainability of Earth's life support system against human-induced stresses is one of the greatest research and policy challenges ever to confront humanity. Can humanity meet this challenge?"