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Introduction
Decades ago, as scientists initially began exploring the possibility that emissions of
carbon dioxide from the burning of fossil fuels could alter the climate of the planet Earth, it
was generally believed that the global climate system was sufficiently stable that any
human-induced impacts would unfold slowly and gradually. Over the past decade,
however, this assumption has been challenged by scientific research in the field of
paleoclimatology, which reveals that the global climate system has been far more unstable
over the past several hundred thousand years than previously believed (Weart, 2003).
There is growing evidence that naturally occurring climatic shifts between glacial and
interglacial eras, which were previously thought to evolve slowly over millennia, have for
the most part taken place in spurts as short as ten or even fewer years. While the science of
abrupt climate change is still in a development stage and substantial investments in
monitoring technologies are needed, policy makers must now contemplate the possibility
that human additions to the greenhouse gas burden of the atmosphere could trigger
significant climate changes within the next few decades, which may have serious, if not
catastrophic, consequences for the natural environment and human communities.
The international global climate change regime, which is based upon the United
Nations Framework Convention on Climate Change of 1992 and the Kyoto Protocol of
1997, implicitly assumes that human impacts on global climate will occur gradually, albeit
much more rapidly than what was previously believed to be the very slow pace of natural
changes. The regime has been developed with the objective of lessening the amount of
climate change that will take place by limiting the buildup of greenhouse gases in the
atmosphere to a level that will avoid highly harmful impacts. The Kyoto Protocol, which
Convention