Q: What is today's most important unreported story?
A: That's easy: abrupt
climate change, the sort of thing where most of the earth returns to
ice-age temperatures in just a decade or two, accompanied by a major
worldwide drought. Then, centuries later, it flips back just as quickly.
This has happened hundreds of times in the past.
The earth's climate has at
least two modes of operation that it flips between, just as your window
air-conditioner cycles between fan and cool with a shudder. And it
doesn't just settle down into the alternate mode: the transition often
has a flicker like an aging fluorescent light bulb. There are sometimes
a half-dozen whiplash cycles between warm-and-wet and cool-and-dusty,
all within one madhouse century. On a scale far larger than we saw in
the El Nino several years ago, major forest fires denude much of the
To the extent the
geophysicists understand the mechanism, it's due to a rearrangement in
the northern extension of the Gulf Stream. A number of computer
simulations, dating back to 1987, of the winds and ocean currents have
shown that gradual global warming can trigger such a mode switch within
several centuries, mostly due to the increased rainfall into the
northern North Atlantic Ocean (if the cold salty surface waters are
diluted by fresh water, they won't flush in the usual manner that allows
more warm water to flow north and lose its heat). Meltwater floods from
Iceland and Greenland will do the job if tropical-warming-enhanced
This has been the major
story in the geophysical sciences of the last decade. I've been puzzled
since 1987 about why this story hasn't been widely reported. A few
newspapers finally started reporting the story in some detail two years
ago but still almost no one knows about it, probably because editors and
readers confuse it with gradual climate change via greenhouse gases.
This longstanding gradual warming story seems to cause the abrupt story
to be sidetracked, even though another abrupt cooling is easily the most
catastrophic outcome of gradual warming, far worse than the usual
economic and ecological burden envisaged.
How would I report it?
Start with the three million year history of abrupt coolings and how
they have likely affected prehuman evolution. Our ancestors lived
through a lot of these abrupt climate changes, and some humans will
survive the next one. It's our civilization that likely won't, just
because the whiplashes happen so quickly that warfare over plummeting
resources leaves a downsized world where everyone hates their neighbors
for good reason. Fortunately, if we get our act together, there are few
things we might do to stabilize the patient, buying some extra time in
the same manner as preventive medicine has extended the human lifespan.
H. CALVIN is a theoretical neurophysiologist on the faculty of the
University of Washington who writes about the brain and evolution. Among
his many books are How Brains Think, The Cerebral Code, and Lingua
ex Machina. He is the author of a cover story for The Atlantic
Great Climate Flip-flop," January 1998, and a forthcoming book,
Cool, Crash and Burn: The Once and Future Climate of Human Evolution.
Further reading on Edge:
for Consciousness: How Subconscious Thoughts Cook on the Backburner: A
Talk by William H. Calvin".