Legislation Will Not Mitigate Climate Change A response to Alan Dupont of the Lowy Institute
William Kininmonth
Weather is what everyone talks about but
climate is what everybody claims to be an expert about. What
is more, the self-styled experts insist that laws should be passed
to ensure climate returns to what it was in pre-industrial times---just
like in Camelot where King Arthur mandates:
Its true!
Its true! The crown has made it clear!
The climate must be perfect all the year. (Lerner and Lowe)
Are 'centuries of fossil fuel use and deforestation'
altering our climate, as claimed by senior fellow Alan Dupont
(The Australian, Opinion 23/6/06)? Is carbon dioxide 'heating
the atmosphere just a little, allowing it to take up and retain
more moisture, which then warms the atmosphere further' as claimed
by scientist, explorer and conservationist Tim Flannery in his
book, The Weather Makers?
The answer to both questions is a resounding
NO. These, and a host of similarly erroneous statements, are
the bases for claims that governments should pass laws to prevent
climate change. However, all the governments of all the nations
could pass laws until the legislators fell exhausted but there
would be no appreciable impact on Earth's climate and its continuing
variability.
We can be confident that human activity
is having only limited impact on Earth's climate because of the
scale of past variability and the insignificance of human activity
compared to the power of nature.
The atmosphere and the oceans are continually
transporting excess solar energy from the tropics to the polar
regions. As a consequence, middle and high latitudes regions
maintain relative warmth in spite of the net radiation cooling
to space. To put this in perspective, the average rate of energy
transport is more than one thousand times the rate that energy
is being generated by all human activity. Our activities are
insignificant. For the optimists, as fossil and nuclear fuel
resources are depleted the climate system represents an enormous
source of renewable energy---if it can be harnessed
Earth's climate was not in balance prior
to industrialisation, as global warming theory would have us
believe. There was no Camelot. The ocean and atmosphere are fluids
in motion that interact and modulate the rate of poleward energy
transport, thus varying the global climate. When transport exceeds
the amount of heat necessary to offset net radiation to space
over polar regions there is warming and ice melt, as happened
during the first few and last few decades of the 20th century.
When transport slows then temperatures fall and ice sheets expand,
as they did from the 1940s to the middle 1970s.
There is abundant evidence to confirm that
the relatively small temperature and ice mass changes of the
20th century are within the bounds of natural variation of the
climate system.
As earth emerged from the last major ice
age between 19,000 and 10,000 years ago, the ice sheets that
were more than a kilometre thick and covered much of North America
and northern Europe melted and sea level rose about 130 metres.
Between 10,000 and 5,000 years ago, polar temperatures were up
to 2 degrees Celsius warmer than now but the Greenland ice mass
did not melt, as alarmists are currently predicting. Even in
the height of summer the temperature of the high elevation Greenland
ice surface is less than minus 10 degrees Celsius.
The global cooling over the past 5 thousand
years has not been regular. Much is written about the general
warmth associated with the ancient Greek and Roman empires and
there is evidence that between two thousand and 15 hundred years
ago European and North American glaciers advanced. The glaciers
retreated during the Medieval Warm Period that occurred between
about 800 and 1200AD, when Iceland and Greenland were colonised
from Europe, but they again advanced during the Little Ice Age,
which was at its peak between about 1600 and 1800AD.
Londoner John Evelyn wrote in January 1684,
as the industrial revolution was stirring, 'men and cattle
perishing in divers (sic) places, and the very seas so locked
up with ice that no vessels could stir out or come in. The fowls,
fish and birds, and all our exotic plants and greens, universally
perishing'. Is this the Camelot to which the Kyoto Protocol
would have us return?
When we acknowledge that climate is forever
varying, and that recurring extreme weather is a natural hazard
facing humankind, then we will begin to take the necessary steps
to mitigate its impacts. In those countries where appropriate
measures are in place, preparedness, early warning and emergency
response systems consistently reduce loss of life associated
with weather and climate extremes. Universally, the material
damage associated with weather and climate extremes continues
to increase. This is largely because of a propensity to build
in hazardous localities, whether by necessity or desire, and
our inability to construct against the forces of nature.
There is much to learn about the climate
system, especially about the oceans that are the flywheels regulating
everyday weather and climate. The extent of the wind-driven ocean
gyres has been recognised since exploration with sailing ships.
However it is only in recent years that a concerted international
effort has commenced to identify, analyse and monitor the sub-surface
circulations and their variations that are important for regulating
climate and associated weather.
It is a delusion to suggest that the science
of climate change is settled. Simplistic explanations, such as
that certain 'greenhouse' gases warm the atmosphere and so higher
concentrations will warm more, are factually incorrect and lead
to poor policy outcomes. The Intergovernmental Panel on Climate
Change (IPCC) recognises that the net effect of water vapour
and carbon dioxide, the principal 'greenhouse' gases, is to cool
the atmosphere. The effect of varying the concentration of these
gases is on the temperature of the land and ocean surfaces, not
directly on the temperature of the atmosphere as is naively claimed.
It is even more of a delusion to accept
that climate predictions made using computer models have any
validity. Non-linear interactions between the components of the
climate system lead to chaotic outcomes. Although the equations
that describe atmospheric motion are non-linear the current predictions,
as described by IPCC, are constrained to a linear relationship
between carbon dioxide concentration and global temperature response.
The different computer models give a range of predictions that
relate to the built in sensitivity of each to carbon dioxide
forcing. Moreover, computer models are not capable of predicting
a return of conditions similar to those of the Little Ice Age.
An inability to predict the future is not
reason for inaction. Equally it is not reason to get on an emotional
bandwagon to address the chimera of anthropogenic global warming,
just for the sake of appearing to be doing something. Australia
has a well-documented history of weather and climate extremes,
be they droughts, floods, tropical cyclones or conditions that
build to support dangerous bushfires. The severe El Nino events
of 1982-83 and 1997-98 demonstrate how a global pattern of disasters
can evolve, impacting especially on developing countries.
Climate, and the intensity and frequency
of weather and climate extremes, will not be changed appreciably
through a reduction of fossil fuel burning. The societal impacts
can, however, be mitigated through coordinated national and international
actions that increase knowledge; that foster preparedness, early
warning and response measures; and that reduces exposure to hazard
through adequate planning guidelines.
Importantly, national energy policy should
not be determined on the spurious ground of averting global warming.
Such policies should be developed on the basis of real economic
and environmental considerations.
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