For thousands of years, the fossil fuel deposits lay locked under the ice
and inaccessible. Ironically, the very process of burning fossil fuels
releases massive amounts of carbon dioxide, or CO2, and forces an increase
in the Earth’s temperature, which in turn melts the Arctic ice, making
available even more oil and gas for energy. Burning these potential oil and
gas finds would further increase CO2 emissions in coming decades, depleting
the Arctic ice even more quickly.
But there is an even more dangerous aspect to the unfolding drama in the
Arctic. While governments and oil giants are hoping the melting ice will
allow them access to the world’s last treasure trove of oil and gas,
climatologists are deeply worried about something else buried under the ice
that, if unearthed, could wreak havoc on the biosphere, with dire
consequences for human life.
Much of the Siberian sub-Arctic region, an area the size of France and
Germany combined, is a vast, frozen peat bog. Before the most recent Ice
Age, the area was mostly grassland, teeming with wildlife. The coming of the
glaciers entombed the organic matter below the permafrost, where it has
remained ever since. Although the surface of Siberia is largely barren,
there is as much organic matter buried underneath the permafrost as there is
in all of the world’s tropical rain forests.
Now the permafrost is thawing on land and along the seabeds. If it occurs in
the presence of oxygen on land, the decomposing of organic matter leads to
the production of CO2. If the permafrost thaws along lake shelves, in the
absence of oxygen, the decomposing matter releases methane. Methane is the
most potent of the greenhouse gases, with a greenhouse effect 23 times that
of CO2.
Katey Walter of the Institute of Arctic Biology at the University of Alaska
in Fairbanks wrote in the journal Nature last year, and in Philosophical
Transactions of the Royal Society in May, that the melting of the permafrost
and subsequent release of methane is a "ticking time bomb."
Walter and her researchers warned of a tipping point sometime within this
century, when the release of methane could create an uncontrollable feedback
effect, dramatically warming the atmosphere, which would in turn warm the
land, lakes and seabed, further melting the permafrost and releasing more
methane. Once that threshold is reached, there will be nothing humans can
do. Scientists suspect that similar events have occurred in the ancient
past, between glacial periods.
Scientists are particularly concerned that the thawing permafrost is also
creating shadow lakes across the Siberian sub-Arctic landscape. The lake
waters have a higher ambient temperature than the surrounding permafrost. As
a result, the permafrost near the lakes thaws more quickly, forcing the
ground surfaces to collapse into the lakes. The stored organic carbon then
decomposes into the lake bottoms. Methane from that decomposition bubbles to
the surface and escapes into the atmosphere. Scientists calculate that
thousands of tons of methane will be released from Arctic lakes as the
permafrost thaws.
A global tragedy of monumental proportions is unfolding at the top of the
world, and the human race is all but oblivious to what’s happening.
When U.S. astronauts stepped onto the moon in 1969, Neil Armstrong’s first
words were, "One small step for man, one giant leap for mankind." The
Russian aquanauts, landing on the Arctic seabed, might just as well have
said, "One small dive for man, one giant leap backward for life on Earth."
…………
Jeremy Rifkin is the author of "The Hydrogen Economy: The Creation of the
World Wide Energy Web and the Redistribution of Power on Earth."