- "We have built a greenhouse, a human greenhouse,
where once there bloomed a sweet and wild garden." -- Bill
- The Arctic Council's recent report on the effects of
global warming in the far north paints a grim picture: global floods,
of polar bears and other marine mammals, collapsed fisheries. But it
a ticking time bomb buried in the Arctic tundra.
- There are enormous quantities of naturally occurring
greenhouse gasses trapped in ice-like structures in the cold northern muds
and at the bottom of the seas. These ices, called clathrates, contain 3,000
times as much methane as is in the atmosphere. Methane is more than 20
times as strong a greenhouse gas as carbon dioxide.
- Now here's the scary part. A temperature increase of
merely a few degrees would cause these gases to volatilize and
into the atmosphere, which would further raise temperatures, which would
release yet more methane, heating the Earth and seas further, and so on.
There's 400 gigatons of methane locked in the frozen arctic tundra - enough
to start this chain reaction - and the kind of warming the Arctic Council
predicts is sufficient to melt the clathrates and release these greenhouse
gases into the atmosphere.
- Once triggered, this cycle could result in runaway global
warming the likes of which even the most pessimistic doomsayers aren't
- An apocalyptic fantasy concocted by hysterical
Unfortunately, no. Strong geologic evidence suggests something similar
has happened at least twice before.
- The most recent of these catastrophes occurred about
55 million years ago in what geologists call the Paleocene-Eocene Thermal
Maximum (PETM), when methane burps caused rapid warming and massive
disrupting the climate for more than 100,000 years.
- The granddaddy of these catastrophes occurred 251 million
years ago, at the end of the Permian period, when a series of methane burps
came close to wiping out all life on Earth.
- More than 94 percent of the marine species present in
the fossil record disappeared suddenly as oxygen levels plummeted and life
teetered on the verge of extinction. Over the ensuing 500,000 years, a
few species struggled to gain a foothold in the hostile environment. It
took 20 million to 30 million years for even rudimentary coral reefs to
re-establish themselves and for forests to regrow. In some areas, it took
more than 100 million years for ecosystems to reach their former healthy
- Geologist Michael J. Benton lays out the scientific
for this epochal tragedy in a recent book, When Life Nearly Died: The
Mass Extinction of All Time. As with the PETM, greenhouse gases, mostly
carbon dioxide from increased volcanic activity, warmed the earth and seas
enough to release massive amounts of methane from these sensitive
setting off a runaway greenhouse effect.
- The cause of all this havoc?
- In both cases, a temperature increase of about 10.8
Fahrenheit, about the upper range for the average global increase today's
models predict can be expected from burning fossil fuels by 2100. But these
models could be the tail wagging the dog since they don't add in the effect
of burps from warming gas hydrates. Worse, as the Arctic Council found,
the highest temperature increases from human greenhouse gas emissions will
occur in the arctic regions - an area rich in these unstable
- If we trigger this runaway release of methane, there's
no turning back. No do-overs. Once it starts, it's likely to play out all
- Humans appear to be capable of emitting carbon dioxide
in quantities comparable to the volcanic activity that started these chain
reactions. According to the U.S. Geological Survey, burning fossil fuels
releases more than 150 times the amount of carbon dioxide emitted by
- the equivalent of nearly 17,000 additional volcanoes the size of Hawaii's
- And that is the time bomb the Arctic Council
- How likely is it that humans will cause methane burps
by burning fossil fuels? No one knows. But it is somewhere between possible
and likely at this point, and it becomes more likely with each passing
year that we fail to act.
- So, forget rising sea levels, melting ice caps, more
intense storms, more floods, destruction of habitats and the extinction
of polar bears. Forget warnings that global warming might turn some of
the world's major agricultural areas into deserts and increase the range
of tropical diseases, even though this is the stuff we're pretty sure will
- Instead, let's just get with the Bush administration's
policy of pre-emption. We can't afford to have the first sign of a failed
energy policy be the mass extinction of life on Earth. We have to act
- John Atcheson, a geologist, has held a variety of policy
positions in several federal government agencies.