THE BIGGEST PROBLEM
IS OUR LACK OF PREPARATION FOR THE ANTHROPOCENE
In 1824, while working in a Paris laboratory on observations of the Earth, Joseph Fourier described the greenhouse effect for the first time: “The temperature [of the Earth] can be augmented by the interposition of the atmosphere, because heat in the state of light finds less resistance in penetrating the air, than in re-passing into the air when converted into non-luminous heat.”
It was a remarkably prescient discovery, given the science of the time. We know now that “heat in the state of light” arrives as high-energy shortwave radiation, able to penetrate atmospheric clouds (or glass windows), and is transformed by contact into infrared, or what Fourier called chaleur obscure (non-luminous heat), which attempts to depart as low-energy long-wave radiation, only to bounce back if obstructed (such as by clouds of greenhouse gases). Fourier appreciated the infrared effect from the work of a contemporary, William Herschel, and was quick to realize that how you warm the Earth is the same as how you warm a greenhouse.
Thirty-seven years later, the Irish physicist John Tyndall demonstrated that water vapor is one of the important components of Earth’s greenhouse shield. “This aqueous vapour is a blanket more necessary to the vegetable life of England than clothing is to man,” Tyndall remarked.
Thirty-seven years after that, Swedish chemist Svante Arrhenius warned that industrial-age coal burning would magnify the natural greenhouse effect. He even provided a number — five degrees Celsius — corresponding with a doubling of atmospheric carbon dioxide.
Thirty-seven years more would pass before carbon emissions from fossil-fuel burning reached one billion metric tons per year, and human population crossed the two billion mark.
Our atmosphere extends a seemingly long ways from the surface of the planet, but the amount of air there is not all that much. If you were to cool that air to a liquid, it would be about 39.2 feet (11.9 meters) deep.
In the 1940s, that air contained about 280 parts per million CO2 gas by volume (ppmv), which was a 10-ppmv jump over the norm of 270 that had prevailed since the Little Ice Age, and a few dozen more ppmv beyond the pre-agricultural norm. If you were to cool that 1940 CO2 volume to a liquid, it would be about the thickness of a page of a newspaper, all over the planet.
By the 1950s, measuring equipment had improved to the point where Gilbert Plass could detail the infrared absorption of various gases; Roger Revelle and Hans Suess could show that seawater was incapable of absorbing the rate of man-made CO2 entering the atmosphere; and Charles David Keeling could produce annual records of rising atmospheric carbon levels from observatory instruments in Hawaii and Antarctica.
Two years after Keeling’s first climb up the slopes of the Mauna Loa volcano, human population crossed the three billion mark.
In 1965, the U.S. President’s Scientific Advisory Committee warned Lyndon B. Johnson that the greenhouse effect was a matter of “real concern.” In 1975, climatologist Wallace Broecker coined the term “global warming” and began warning that sudden climate shifts were not historically unprecedented.
The decade that followed brought a spate of in-depth inquiries by scientific bodies, government committees, and the United Nations. In 1988, the Intergovernmental Panel on Climate Change (IPCC) was formed to report the collected findings in a nonpartisan way.
By 1987, 20 years after Keeling’s fateful ascent of the volcano, and nearly a century after Arrhenius’s calculations, human population had reached five billion.
Following the release of the first IPCC report, the governments of the world convened the 1992 Earth Summit in Rio de Janeiro. There they agreed to the United Nations Framework Convention on Climate Change, with a key objective of “stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.”
Three years later, the second IPCC report described how “dangerous anthropogenic interference” with the climate system was already occurring. Meanwhile, virtually no progress was made on any of the goals that had been set for emissions reductions. Business-as-usual had taken control, and the denial machine had gone into overdrive.
In 1999, human population reached six billion.
In 2001, the IPCC Third Assessment Report issued even stronger warnings, based on new evidence of dangerous anthropogenic interference. In response, the U.N. enacted the Kyoto Protocol to mandate reductions, with the target of returning the world to its 1990 emissions level by 2012. These voluntary reductions failed to significantly alter the growth of fossil fuel consumption, or slow the admission of powerful new members to the greenhouse-gas-producer family, such as China, India, Indonesia, and Brazil. World population was still growing, and everyone seemed to want a house filled with the latest consumer appliances, plus a two-car garage, a chicken in every pot, and a pot roast in the oven.
By 2006, atmospheric CO2 had risen to 380 ppmv, or about one and a half sheets of newspaper, if cooled and laid across the ground.
In 2007, carbon emissions from fossil-fuel burning reached 8 billion metric tons per year (8 GtC/yr), with a comparable amount being generated by animals raised for slaughter. The IPCC’s Fourth Assessment Report concluded, almost anticlimactically, that it was now certain that humanity’s emissions of greenhouse gases are responsible for climate change. At framework negotiations in Bali, world governments agreed to the two-year “Bali roadmap” aimed at hammering out a new global treaty by the end of 2009.
If your species loses its economic underpinnings, your position on the economic development chart could fall back to where you were in 1930, or 1830, or even 1330, but you are still around as a species, assuming you don’t totally lose your cool and just nuke everything in sight on your way down.
In contrast, if your species loses its climate underpinnings, it’s “Game over, man.” You not only take down the higher vertebrates, homo included, but everything alive on this third rock from the Sun, potentially even the microbes in deep caves and ocean depths. Earth, meet Venus.
Recent studies with global climate models suggest that new equilibrium could be found between 5 and 10 degrees warmer, but that at some point the natural damping effect is overwhelmed and a runaway greenhouse warming transforms the climate of Earth to something more resembling Venus.
On May 19, 2009, Woods Hole Research Laboratory and the Massachusetts Institute of Technology released a study involving more than 400 supercomputer runs of the best climate data currently available. Conclusion: The effects of climate change are twice as severe as estimated just six years ago, and the probable median of surface warming by 2100 is now 5.2 °C, compared to a finding of 2.4 °C as recently as 2003. Moreover, the study rated the possibility of warming to 7.4 °C by the year 2100 (and still accelerating thereafter) at 90 percent — in spite of our feeble efforts at “cap and trade,” “contraction and convergence,” or a “clean development mechanism.”
Another report, released in 2009 by the Global Humanitarian Forum, found that 300,000 deaths per year are already attributable to climate-change-related weather, food shortages, and disease. That figure could be called our baseline, or background count — of the 20th-century-long experience of a temperature change of less than 1 °C.
These two reports set the stage for the findings released by the U.S. Advisory Committee on Global Change Research, Global Climate Change Impacts in the United States. The authoring team was headed by senior climate scientists at the National Oceanic and Atmospheric Administration and included half a dozen government agencies and laboratories, and senior researchers from a dozen universities. Just reading the introduction is refreshing, because it cuts through so much of the tone-deafness that passes for public debate these days.
While limited solely to the continental United States and Hawaii, the Impacts report takes the projections for the coming decades to about as fine a grain as can be seen, given the behavior of interrelated and reciprocating climate systems undergoing rapid destabilization.
The European heat wave of 2003 [with more than 30,000 heat fatalities] is an example of the type of extreme heat event that is likely to become much more common. If greenhouse gas emissions continue to increase, by the 2040s more than half of European summers will be hotter than the summer of 2003, and by the end of this century, a summer as hot as that of 2003 will be considered unusually cool.
Recent findings indicate that it is very likely that the strength of the North Atlantic Ocean circulation will decrease over the course of this century in response to increasing greenhouse gases. . . . The best estimate is that the strength of this circulation will decrease 25 to 30 percent in this century, leading to a reduction in heat transfer to the North Atlantic. It is considered very unlikely that this circulation would collapse entirely during the next 100 years or so, although it cannot be ruled out.