The pink and orange gamete bundles that look like caviar eggs but are actually hermaphroditic clusters of eggs and sperm are migrating up the polyps toward the oral cavities, the corals' single, multipurpose orifices. Each night these bundles have been growing and stretching the polyps until they resemble nothing so much as minuscule pregnant bellies. On this night, the fourth night after the full moon of the austral springtime, the gametes are beginning to crown, like human heads in their birth canals.
I check my watch. When I glance back to the coral, the ocean is transformed. I blink, thinking I'm seeing things. But it's really here—the black water engulfed in a pink and orange blizzard flowing toward the surface. Within seconds, countless billions of magenta and tangerine gamete bundles have been birthed from their polyps and are floating upward on the buoyancy of the fatty eggs.
Those of us underwater at this moment are also transformed by the bundles, which collect under the folds and angles of our wet suits, buoyancy control devices, dive masks, and regulators. Colorful gametes tangle in our hair. If we could breathe water, we'd be breathing them. The rate of the blizzard amplifies until the light from the strobes blinds us. Clicking to a lower setting, I see eruptions of milky white sperm pulsing rhythmically from nearby sponges and sea cucumbers, polychaete worms and giant clams.
On this night, as many as half of the reef-building corals—perhaps 150 species—plus a host of other invertebrates inhabiting the 1,200 miles of Australia's Great Barrier Reef, are spawning. It's an ancient ritual, maybe as old as the 200 million-plus years that scleractinian corals have been alive. These corals emerged in the darkest days after the Permian-Triassic extinction, when the planet was impoverished nearly beyond repair by massive global climate change, and when almost all life died in hot, dry, and iceless conditions. Since then they have survived two subsequent mass extinctions, including the one that killed the non-avian dinosaurs.
Already, manta rays with six-foot wingspans are sailing into view, mouths open, filtering the eggs from the water. At the outer range of our strobes, reef sharks are circling, preparing to gorge on those that have come to feast. From the cold and perpetually dark reaches of the deep known as the mesopelagic, fish that glow in the dark, and live a mile or more below the tidal, lunar, and seasonal influences that trigger the mass spawning, are rising toward it now, preparing to devour the bonanza they have perceived in ways we can't.
No modern human knew of the mass spawning of corals on the Great Barrier Reef before 1982, when marine biologists accidentally happened upon it. Since then, other spawnings adhering to their own unique schedules have been discovered on many reef systems. Somehow, spineless, brainless, eyeless, earless, immotile marine animals that meet all our criteria for zero intelligence manage to synchronize their activities to ensure survival. Otherwise, all their gametes—a year's investment in energy—would launch off into open water without ever finding suitable partners. While an individual animal might survive such behavior for the term of its natural life, the species could not.
12 ASTEROIDS AND EVOLVING INTO WISDOM
IN 2004, JOHN SCHELLNHUBER, distinguished science adviser at the Tyndall Centre for Climate Change Research in the United Kingdom, identified 12 global-warming tipping points, any one of which, if triggered, will likely initiate sudden, catastrophic changes across the planet. Odds are you've never heard of most of these tipping points, even though your entire genetic legacy—your children, your grandchildren, and beyond—may survive or not depending on their status.
Why is this? Is it likely that 12 asteroids on known collision courses with earth would garner such meager attention? Remarkably, we appear to be doing what even the simplest of corals does not: haphazardly tossing our metaphorical spawn into a ruthless current and hoping for a fertile future. We do this when we refuse to address global environmental issues with urgency; when we resist partnering for solutions; and when we continue with accelerating momentum, and with what amounts to malice aforethought, to behave in ways that threaten our future.
A 2005 study by Anthony Leiserowitz, published in Risk Analysis, found that while most Americans are moderately concerned about global warming, the majority—68 percent—believe the greatest threats are to people far away or to nonhuman nature. Only 13 percent perceive any real risk to themselves, their families, or their communities. As Leiserowitz points out, this perception is critical, since Americans constitute only 5 percent of the global population yet produce nearly 25 percent of the global carbon dioxide emissions. As long as this dangerous and delusional misconception prevails, the chances of preventing Schellnhuber's 12 points from tipping are virtually nil.
So what will it take to trigger what we might call the 13th tipping point: the shift in human perception from personal denial to personal responsibility? Without a 13th tipping point, we can't hope to avoid global mayhem. With it, we can attempt to put into action what we profess: that we actually care about our children's and grandchildren's futures.
Science shows that we are born with powerful tools for overcoming our perilous complacency. We have the genetic smarts and the cultural smarts. We have the technological know-how. We even have the inclination. The truth is we can change with breathtaking speed, sculpting even "immutable" human nature. Forty years ago many people believed human nature required blacks and whites to live in segregation; 30 years ago human nature divided men and women into separate economies; 20 years ago human nature prevented us from defusing a global nuclear standoff. Nowadays we blame human nature for the insolvable hazards of global warming.
The 18th-century taxonomist Carolus Linnaeus named us Homo sapiens, from the Latin sapiens, meaning "prudent, wise." History shows we are not born with wisdom. We evolve into it.
CLIMATE CLIQUES AND NAYSAYERS
EISEROWITZ'S STUDY OF risk perception found that Americans fall into "interpretive communities"—cliques, if you will, sharing similar demographics, risk perceptions, and worldviews. On one end of this spectrum are the naysayers: those who perceive climate change as a very low or nonexistent danger. Leiserowitz found naysayers to be "predominantly white, male, Republican, politically conservative, holding pro-individualism, pro-hierarchism, and anti-egalitarian worldviews, anti-environmental attitudes, distrustful of most institutions, highly religious, and to rely on radio as their main source of news." This group presented five rationales for rejecting danger: belief that global warming is natural; belief that it's media/environmentalist hype; distrust of science; flat denial; and conspiracy theories, including the belief that researchers create data to ensure job security.
We might wonder how these naysayers, who represent only 7 percent of Americans yet control much of our government, got to be the way they are. A study of urban American adults by Nancy Wells and Kristi Lekies of Cornell University sheds some light on environmental attitudes. Wells and Lekies found that children who play unsupervised in the wild before the age of 11 develop strong environmental ethics. Children exposed only to structured hierarchical play in the wild—through, for example, Boy Scouts and Girl Scouts, or by hunting or fishing alongside supervising adults—do not. To interact humbly with nature we need to be free and undomesticated in it. Otherwise, we succumb to hubris in maturity. The fact that few children enjoy free rein outdoors anymore bodes poorly for our future decision-makers.
Another study, this one from the Earth Institute at Columbia University, found an ominous silence when it comes to educating American K-12 students on the relationship between our personal behavior and our environment: that the size and inefficiency of our cars, homes, and appliances, our profligate fuels, our love of disposables, and the effects of buying more than we need actually undermine our prospects on earth. Slightly more time is spent teaching kids how the environment can affect us, overpowering humanity with floods, droughts, storms, earthquakes, climate change. But in our overall failure to illuminate the interdependence between Homo sapiens and earth we withhold critical knowledge from those whose lives depend upon it most.
Many of today's kids recreate in the unwilderness of the shopping mall, where messages of prudence and wisdom are overwhelmed by the consumerism that feeds global warming. We send our kids to the mall because we fear the dangers outside. We could hardly be more wrong in our assessment of risk.
THE ALARMISTS AND THE ACROBAT
ON THE OTHER END of Leiserowitz's spectrum of perception regarding global warming is an interpretive community he calls the alarmists, generally comprised of individuals holding pro-egalitarian, anti-individualist, and antihierarchical worldviews, who are supportive of government policies to mitigate climate change, even so far as raising taxes. Members of this group are likely to have taken personal action to reduce greenhouse gas emissions. Collectively, alarmists compose 11 percent of Americans, with the remaining interpretive communities falling considerably closer to the alarmists than the naysayers in the spectrum—suggesting the gap might be cinched by sustained public education on the neighborhood dangers likely to arise in a changed global climate.
Hurricane Katrina provided a wake-up call for how bad it can get in the neighborhood, and may prove a tipping point itself. Yet long before its rampage, American kids were coloring pictures of the first icon of global environmentalism, the Amazon. Its billion-plus acres of rivers and rainforest—its trees collecting and containing excessive greenhouse gases from the atmosphere—were our primer for the revolutionary notion that the earth's neighborhoods are interdependent.
Today Amazonia is the most famous of Schellnhuber's tipping points. For a generation, kids have grown up learning that the Amazon is at risk from massive deforestation. But even if clearcutting were to halt, climate models forecast that a warming globe will convert the wet Amazonia forest into savanna within this century, and the loss of trees will render the region a net CO2 producer, further accelerating global warming.
Amazonia's tipping point might be fast approaching. The year 2005 saw the driest conditions in 40 years, with wildfires raging unabated, and 2006 is looking worse, raising alarms that environmental synergism is already in play as changes become self-sustaining and reinforce one another. Dan Nepstadt of the Woods Hole Research Center in Massachusetts questions whether the warming of the Atlantic (the tropical North Atlantic rose 1.7 degrees Fahrenheit above the 1901-1970 average in 2005) is affecting airflow over the Amazon, leading to drier and fierier conditions there.
Changes in the currents of the North Atlantic constitute another tipping point. As the Atlantic warms, ice caps melt, diluting the ocean and potentially shutting down its thermohaline circulation (THC), the oceanic river currently delivering the thermal equivalent of 500,000 power stations' worth of warmth to Europe. A 2005 study published in Nature found that after 50 years of monitoring, a critical component of the THC had suddenly slowed by 30 percent.
The fate of this circulation is closely linked to one of Schellnhuber's more notorious tipping points, the Greenland Ice Sheet. Encompassing 6 percent of the earth's freshwater supply, this ice, if melted, would raise sea levels by about 23 feet worldwide—not counting ice loss from the rest of the Arctic and the Antarctic. A study by NASA and the University of Kansas showed the decline of Greenland's ice unexpectedly doubled between 1996 and 2005, as glaciers surged into the sea with unpredicted speed. More worrying, the area of melt shifted 300 nautical miles north during the last four years of the study, indicating the warmth is spreading rapidly.
One tipping point affects the other in a balance as delicate as that of an acrobat's spinning plates. Greenland's increasing freshwater flow into the North Atlantic will certainly impact the THC. Warm water recirculating within the central Atlantic may further rearrange airflow over the Amazon, accelerating its dry-down and tree loss, and potentially freeing as much carbon dioxide from its enormous reservoir as the 20th century's total fossil fuel output. A sudden Amazonian release would surely melt whatever of Greenland hadn't already melted, crashing the THC and drastically cooling Europe—in the worst-case scenario, freezing it solid. Although we like to compartmentalize, nature does not. Biology and climatology are the indivisible warp and weft of earth's living fabric.