THE THREAT OF CLIMATE CHANGE (Jeremy Rifkin, 2002)
GOODBYE CRUEL WORLD
A report by top US scientists on climate change suggests that catastrophe
could be imminent
The Guardian, Friday March 1,
We live in a world that has become so desensitised by watching calamities
unfold on global television - both natural and human-induced - that it takes
something really spectacular even to get our attention.
And it usually has to be visually dramatic to register, much less elicit a
deep emotional response - such as the tragic events of September 11.
Recently, I came across a frightening report published by the US National
Academy of Sciences (NAS) - the nation's most august scientific body. Yet,
because there was no visually provocative content, the report had received only
a couple of short paragraphs tucked away inside a few newspapers.
Here is what the academy had to say: it is possible that the global
warming trend projected over the course of the next 100 years could, all of a
sudden and without warning, dramatically accelerate in just a handful of years -
forcing a qualitative new climatic regime which could undermine ecosystems and
human settlements throughout the world, leaving little or no time for plants,
animals and humans to adjust.
The new climate could result in a wholesale change in the earth's
environment, with effects that would be felt for thousands of years. If the
projections and warnings in this study turn out to be prophetic, no other
catastrophic event in all of recorded history will have had as damaging an
impact on the future of human civilisation and the life of the planet.
A year ago the UN intergovernmental panel on climate change (IPCC) issued
a voluminous report forecasting that global average surface temperature is
likely to rise by 1.4 to 5.8 degrees centigrade between now and 2100. If that
projection holds up, we were told, the change in temperature forecast for the
next 100 years will be larger than any climate change on earth in more than
The impacts on the earth's biosphere are going to be of a qualitative
kind. To understand how significant this rise in temperature is likely to be, we
need to keep in mind that a 5 degrees centigrade increase in temperature between
the last ice age and today resulted in much of the northern hemisphere of the
planet going from being buried under thousands of feet of ice to being ice-free.
The UN study predicts that a temperature rise of 1.4-5.8 degrees
centigrade over the course of the coming century could include the melting of
glaciers and the Arctic polar cap, sea water rise, increased precipitation and
storms and more violent weather patterns, destabilisation and loss of habitats,
migration northward of ecosystems, contamination of fresh water by salt water,
massive forest dieback, accelerated species extinction and increased droughts.
The IPCC report also warns of adverse impacts on human settlements,
including the submerging of island nations and low-lying countries, diminishing
crop yields, especially in the southern hemisphere, and the spread of tropical
disease northward into previously temperate zones.
The newly released NAS report begins by noting that the current
projections about global warming and its ecological, economic and social impacts
cited in the UN report are based on the assumption of a steady upward climb in
temperatures, more or less evenly distributed over the course of the 21st
century. But that assumption, they say, may be faulty - there is a possibility
that temperatures could rise suddenly in just a few years' time, creating a new
climatic regime virtually overnight.
They also point out that abrupt changes in climate, whose effects are long
lasting, have occurred repeatedly in the past 100,000 years. For example, at the
end of the Younger-Dryas interval about 11,500 years ago, "global climate
shifted dramatically, in many regions by about one-third to one-half the
difference between ice age and modern conditions, with much of the change
occurring over a few years".
According to the study: "An abrupt climate change occurs when the climate
system is forced to cross some threshold, triggering a transition to a new state
at a rate determined by the climate system itself and faster than the cause."
Moreover, the paleoclimatic record shows that "the most dramatic shifts in
climate have occurred when factors controlling the climate system were
changing". Given the fact that human activity - especially the burning of fossil
fuels - is expected to double the CO<->2 content emitted into the atmosphere in
the current century, the conditions could be ripe for an abrupt change in
climate around the world, perhaps in only a few years.
What is really unnerving is that it may take only a slight deviation in
boundary conditions or a small random fluctuation somewhere in the system "to
excite large changes ... when the system is close to a threshold", says the NAS
An abrupt change in climate, of the kind that occurred during the Younger-Dryas
interval, could prove catastrophic for ecosystems and species around the world.
During that particular period, for instance, spruce, fir and paper birch trees
experienced mass extinction in southern New England in less than 50 years. The
extinction of horses, mastodons, mammoths, and sabre-toothed tigers in North
America were greater at that time than in any other extinction event in millions
The committee lays out a potentially nightmarish scenario in which random
triggering events take the climate across the threshold into a new regime,
causing widespread havoc and destruction.
Ecosystems could collapse suddenly with forests decimated in vast fires
and grasslands drying out and turning into dust bowls. Wildlife could disappear
and waterborne diseases such as cholera and vector-borne diseases such as
malaria, dengue and yellow fever, could spread uncontrollably beyond host
ranges, threatening human health around the world.
The NAS concludes its report with a dire warning: "On the basis of the
inference from the paleoclimatic record, it is possible that the projected
change will occur not through gradual evolution, proportional to greenhouse gas
concentrations, but through abrupt and persistent regime shifts affecting
subcontinental or larger regions - denying the likelihood or downplaying the
relevance of past abrupt changes could be costly."
Global warming represents the dark side of the commercial ledger for the
industrial age. For the past several hundred years, and especially in the 20th
century, human beings burned massive amounts of "stored sun" in the form of
coal, oil and natural gas, to produce the energy that made an industrial way of
life possible. That spent energy has accumulated in the atmosphere and has begun
to adversely affect the climate of the planet and the workings of its many
If we were to measure human accomplishments in terms of the sheer impact
our activities have had on the life of the planet, then we would sadly have to
conclude that global warming is our most significant accomplishment to date,
albeit a negative one.
We have affected the biochemistry of the earth and we have done it in less
than a century. If a qualitative climate change were to occur suddenly in the
coming century - within less than 10 years - as has happened many times before
in geological history, we may already have written our epitaph.
When future generations look back at this period, tens of thousands of
years from now, it is possible that the only historical legacy we will have left
them in the geologic record is a great change in the earth's climate and its
impact on the biosphere.
Jeremy Rifkin is the author of The Biotech Century (Gollancz) and
president of the Foundation on Economic Trends in Washington DC.
The National Academy of Sciences report is at: http://www.nap.edu/books/0309074347/html/