Has The Age
Of Chaos Begun?
By Mike Davis
08 October, 2005
genesis of two category-five hurricanes (Katrina and Rita) in a row
over the Gulf of Mexico is an unprecedented and troubling occurrence.
But for most tropical meteorologists the truly astonishing "storm
of the decade" took place in March 2004. Hurricane Catarina --
so named because it made landfall in the southern Brazilian state of
Santa Catarina -- was the first recorded south Atlantic hurricane in
had long excluded the possibility of such an event; sea temperatures,
experts claimed, were too low and wind shear too powerful to allow tropical
depressions to evolve into cyclones south of the Atlantic Equator. Indeed,
forecasters rubbed their eyes in disbelief as weather satellites down-linked
the first images of a classical whirling disc with a well-formed eye
in these forbidden latitudes.
In a series of recent
meetings and publications, researchers have debated the origin and significance
of Catarina. A crucial question is this: Was Catarina simply a rare
event at the outlying edge of the normal bell curve of South Atlantic
weather -- just as, for example, Joe DiMaggio's incredible 56-game hitting
streak in 1941 represented an extreme probability in baseball (an analogy
made famous by Stephen Jay Gould) -- or was Catarina a "threshold"
event, signaling some fundamental and abrupt change of state in the
planet's climate system?
of environmental change and global warming have long been haunted by
the specter of nonlinearity. Climate models, like econometric models,
are easiest to build and understand when they are simple linear extrapolations
of well-quantified past behavior; when causes maintain a consistent
proportionality to their effects.
But all the major
components of global climate -- air, water, ice, and vegetation -- are
actually nonlinear: At certain thresholds they can switch from one state
of organization to another, with catastrophic consequences for species
too finely-tuned to the old norms. Until the early 1990s, however, it
was generally believed that these major climate transitions took centuries,
if not millennia, to accomplish. Now, thanks to the decoding of subtle
signatures in ice cores and sea-bottom sediments, we know that global
temperatures and ocean circulation can, under the right circumstances,
change abruptly -- in a decade or even less.
example is the so-called "Younger Dryas" event, 12,800 years
ago, when an ice dam collapsed, releasing an immense volume of meltwater
from the shrinking Laurentian ice-sheet into the Atlantic Ocean via
the instantly-created St. Lawrence River. This "freshening"
of the North Atlantic suppressed the northward conveyance of warm water
by the Gulf Stream and plunged Europe back into a thousand-year ice
mechanisms in the climate system such as relatively small changes
in ocean salinity -- are augmented by causal loops that act as amplifiers.
Perhaps the most famous example is sea-ice albedo: The vast expanses
of white, frozen Arctic Ocean ice reflect heat back into space, thus
providing positive feedback for cooling trends; alternatively, shrinking
sea-ice increases heat absorption, accelerating both its own further
melting and planetary warming.
amplifiers, chaos -- contemporary geophysics assumes that earth history
is inherently revolutionary. This is why many prominent researchers
-- especially those who study topics like ice-sheet stability and North
Atlantic circulation -- have always had qualms about the consensus projections
of the Intergovernmental Panel on Climate Change (IPCC), the world authority
on global warming.
In contrast to Bushite
flat-Earthers and shills for the oil industry, their skepticism has
been founded on fears that the IPCC models fail to adequately allow
for catastrophic nonlinearities like the Younger Dryas. Where other
researchers model the late 21st-century climate that our children will
live with upon the precedents of the Altithermal (the hottest phase
of the current Holocene period, 8000 years ago) or the Eemian (the previous,
even warmer interglacial episode, 120,000 years ago), growing numbers
of geophysicists toy with the possibilities of runaway warming returning
the earth to the torrid chaos of the Paleocene-Eocene Thermal Maximum
(PETM: 55 million years ago) when the extreme and rapid heating of the
oceans led to massive extinctions.
Dramatic new evidence
has emerged recently that we may be headed, if not back to the dread,
almost inconceivable PETM, then to a much harder landing than envisioned
by the IPCC.
As I flew toward
Louisiana and the carnage of Katrina three weeks ago, I found myself
reading the August 23rd issue of EOS, the newsletter of the American
Geophysical Union. I was pole-axed by an article entitled "Arctic
System on Trajectory to New, Seasonally Ice-Free State," co-authored
by 21 scientists from almost as many universities and research institutes.
Even two days later, walking among the ruins of the Lower Ninth Ward,
I found myself worrying more about the EOS article than the disaster
The article begins
with a recounting of trends familiar to any reader of the Tuesday science
section of the New York Times: For almost 30 years, Arctic sea ice has
been thinning and shrinking so dramatically that "a summer ice-free
Arctic Ocean within a century is a real possibility." The scientists,
however, add a new observation -- that this process is probably irreversible.
"Surprisingly, it is difficult to identify a single feedback mechanism
within the Arctic that has the potency or speed to alter the system's
An ice-free Arctic
Ocean has not existed for at least one million years and the authors
warn that the Earth is inexorably headed toward a "super-interglacial"
state "outside the envelope of glacial-interglacial fluctuations
that prevailed during recent Earth history." They emphasize that
within a century global warming will probably exceed the Eemian temperature
maximum and thus obviate all the models that have made this their essential
scenario. They also suggest that the total or partial collapse of the
Greenland Ice Sheet is a real possibility -- an event that would definitely
throw a Younger Dryas wrench into the Gulf Stream.
If they are right,
then we are living on the climate equivalent of a runaway train that
is picking up speed as it passes the stations marked "Altithermal"
and "Eemian." "Outside the envelope," moreover,
means that we are not only leaving behind the serendipitous climatic
parameters of the Holocene -- the last 10,000 years of mild, warm weather
that have favored the explosive growth of agriculture and urban civilization
-- but also those of the late Pleistocene that fostered the evolution
of Homo sapiens in eastern Africa.
undoubtedly will contest the extraordinary conclusions of the EOS article
and -- we must hope -- suggest the existence of countervailing forces
to this scenario of an Arctic albedo catastrophe. But for the time being,
at least, research on global change is pointing toward worst-case scenarios.
All of this, of
course, is a perverse tribute to industrial capitalism and extractive
imperialism as geological forces so formidable that they have succeeded
in scarcely more than two centuries -- indeed, mainly in the last fifty
years -- in knocking the earth off its climatic pedestal and propelling
it toward the nonlinear unknown.
The demon in me
wants to say: Party and make merry. No need now to worry about Kyoto,
recycling your aluminum cans, or using too much toilet paper, when,
soon enough, we'll be debating how many hunter-gathers can survive in
the scorching deserts of New England or the tropical forests of the
The good parent
in me, however, screams: How is it possible that we can now contemplate
with scientific seriousness whether our children's children will themselves
have children? Let Exxon answer that in one of their sanctimonious ads.
is the author of many books including City of Quartz, Dead Cities and
Other Tales, and the just-published Monster at Our Door, The Global
Threat of Avian Flu (The New Press) as well as the forthcoming Planet
of Slums (Verso).
© 2005 Tom Engelhardt