http://www.fraserinstitute.ca/admin/books/files/ScienceIsntSettled.pdf
"Climate records are dominated by a high density of measurements
from a small portion of the earth’s land surface.
Only the continental United States and western Europe
have many closely spaced stations that have operated for
well over 00 years. Few observations are available from
sparsely inhabited land areas or in ocean areas except
from islands and shipping lanes"
"Many important global climate records are too short to
convey information about long-term trends. For example,
Environment Canada’s record that ostensibly covers
the second largest country on earth is only scientifically
valid and official from 948. In fact, there are fewer stations
in Canada today than there were in 960."
"Land surface temperature records are biased by the
“urban heat island effect.” In 952 T.J. Chandler found that
Greater London was much warmer than the surrounding
countryside. Failure to account for local warming in cities
led to some claims of dramatic warming in the 980s
and 990s and, while adjustments are made today and
the predictions of warming significantly reduced, some
researchers believe the adjustments to be inadequate."
The upper air temperature record disagrees with the surface
record. Temperatures above the surface are measured
by weather balloon instruments and by satellites.
Weather balloons have been launched routinely for over
50 years but few observations are made in many areas
of the world. Starting in 978, satellites have taken temperatures
down through the atmosphere over the entire
globe. Theoretically, the lower part of the atmosphere
should warm at about the same rate as the surface, which
has warmed rapidly since the late 970s. However, both
weather balloon and satellite data sets show much less
warming in the lower atmosphere than at the surface,
although recent examination of all data sets has resulted
in adjustments that reduce the disagreements.
To summarize the first major limitation, climate trends
using any source of observed data, including surface stations,
weather balloons, and satellites, are uncertain due
to short length of the records and because of the need
for adjustments to correct for artificial discontinuities
such as instrument or satellite changes. However, there
is general consensus that there has been global surface
warming around 0.6° C or ° F since the late 800s. The
warming was concentrated into two periods from 90 to
945 and since 976, with cooling around 0.2° C or 0.3° F
between 945 and 976.
The second limitation upon the usefulness of climate
models in the formation of public policy is that future
climate trends are projected, not by simply extrapolating
recent trends, but by using climate models with deficiencies
that make the projected trends very unreliable.
Climate models oversimplify many poorly understood
climate processes. Assumptions and parameters are
adjusted in different modeling efforts until the model
produces estimates that are within what the modelers
believe to be plausible. For example, thunderstorms
are too small to appear in even an advanced climate
model but account for almost all of the rainfall in many
tropical areas. Models estimate rainfall from thunderstorms
by simple rules called “parameterizations,” that
may give realistic amounts of rainfall in some areas but
not in others.
Results from models are contradictory. Different climate
models, or the same model run with different assumptions,
produce significantly different results when the
same data is run through them. The result of most
interest is the “climate sensitivity,” which estimates the
amount of atmospheric warming that would occur from
a doubling of carbon-dioxide levels. Models that realistically
depict the climate trends of the last 00 years or
so may still produce sensitivity values ranging anywhere
from .5˚C to 4.5˚C.
Models fail to account for aerosols properly because their
microscopic effects are not fully understood. Aerosols
are particles (both natural and man-made) in the atmosphere.
Some aerosols reflect solar radiation and cause
cooling. Other aerosols absorb radiation and warm one
layer of the atmosphere, while shading and cooling lower
layers and the surface. Aerosols produce indirect effects
by making it either easier or more difficult for clouds
to form, and for precipitation to fall. Aerosols can also
make both clouds and snow surfaces darker. Models are
currently based on the assumption that the cooling effect
from reflective particles is much larger than the warming
effect from absorption of sunlight by dark particles.
Scenarios of future concentrations of greenhouse gases
are based on dubious assumptions about the future.
These scenarios depend on other models of projected
growth of population, economies, and energy use. Some
projections are so dubious that MIT’s Dr. Richard Lindzen,
a lead author of one of the IPCC science reports, has
referred to them as “children’s exercises.” As researchers
Ian Castles, formerly the head of Australia’s national
office of statistics, and David Henderson of the Westminster
Business School and formerly the chief economist
of the OECD, point out, when estimating potential
future climate changes, IPCC’s modelers inappropriately
compared future estimates of GDP in terms of exchange
rates rather than purchasing power parity. This produces
GDP estimates that are significantly inflated, leading to
estimates of greenhouse-gas producing activity that are
similarly inflated. Castles observes that if such assumptions
are correct, then the average income of South Africans
will have overtaken that of Americans by a very
wide margin by the end of the century. Because of this
economic error, the IPCC scenarios of the future also
suggest that relatively poor developing countries such as
Algeria, Argentina, Libya, Turkey, and North Korea will
all surpass the United States.
Canada’s ratification of the Kyoto protocol, if it is treated
seriously and attempts are made to reduce Canada’s
greenhouse gas emissions by nearly 30% in the next few
years (the estimated reduction required of Canada), is
likely to have a major impact on the future of the Canadian
economy and the allocation of scarce environmental
resources. That ratification relied largely on frightening
scenarios generated by computer climate models that are
simply not sophisticated enough to serve as meaningful
guides to instituting public policy. Though politicians
such as Environment Minister David Anderson claim
that “the science is solid,” even a cursory inspection of
the many problems with computer climate models suggests
it is anything but.
"Climate records are dominated by a high density of measurements
from a small portion of the earth’s land surface.
Only the continental United States and western Europe
have many closely spaced stations that have operated for
well over 00 years. Few observations are available from
sparsely inhabited land areas or in ocean areas except
from islands and shipping lanes"
"Many important global climate records are too short to
convey information about long-term trends. For example,
Environment Canada’s record that ostensibly covers
the second largest country on earth is only scientifically
valid and official from 948. In fact, there are fewer stations
in Canada today than there were in 960."
"Land surface temperature records are biased by the
“urban heat island effect.” In 952 T.J. Chandler found that
Greater London was much warmer than the surrounding
countryside. Failure to account for local warming in cities
led to some claims of dramatic warming in the 980s
and 990s and, while adjustments are made today and
the predictions of warming significantly reduced, some
researchers believe the adjustments to be inadequate."
The upper air temperature record disagrees with the surface
record. Temperatures above the surface are measured
by weather balloon instruments and by satellites.
Weather balloons have been launched routinely for over
50 years but few observations are made in many areas
of the world. Starting in 978, satellites have taken temperatures
down through the atmosphere over the entire
globe. Theoretically, the lower part of the atmosphere
should warm at about the same rate as the surface, which
has warmed rapidly since the late 970s. However, both
weather balloon and satellite data sets show much less
warming in the lower atmosphere than at the surface,
although recent examination of all data sets has resulted
in adjustments that reduce the disagreements.
To summarize the first major limitation, climate trends
using any source of observed data, including surface stations,
weather balloons, and satellites, are uncertain due
to short length of the records and because of the need
for adjustments to correct for artificial discontinuities
such as instrument or satellite changes. However, there
is general consensus that there has been global surface
warming around 0.6° C or ° F since the late 800s. The
warming was concentrated into two periods from 90 to
945 and since 976, with cooling around 0.2° C or 0.3° F
between 945 and 976.
The second limitation upon the usefulness of climate
models in the formation of public policy is that future
climate trends are projected, not by simply extrapolating
recent trends, but by using climate models with deficiencies
that make the projected trends very unreliable.
Climate models oversimplify many poorly understood
climate processes. Assumptions and parameters are
adjusted in different modeling efforts until the model
produces estimates that are within what the modelers
believe to be plausible. For example, thunderstorms
are too small to appear in even an advanced climate
model but account for almost all of the rainfall in many
tropical areas. Models estimate rainfall from thunderstorms
by simple rules called “parameterizations,” that
may give realistic amounts of rainfall in some areas but
not in others.
Results from models are contradictory. Different climate
models, or the same model run with different assumptions,
produce significantly different results when the
same data is run through them. The result of most
interest is the “climate sensitivity,” which estimates the
amount of atmospheric warming that would occur from
a doubling of carbon-dioxide levels. Models that realistically
depict the climate trends of the last 00 years or
so may still produce sensitivity values ranging anywhere
from .5˚C to 4.5˚C.
Models fail to account for aerosols properly because their
microscopic effects are not fully understood. Aerosols
are particles (both natural and man-made) in the atmosphere.
Some aerosols reflect solar radiation and cause
cooling. Other aerosols absorb radiation and warm one
layer of the atmosphere, while shading and cooling lower
layers and the surface. Aerosols produce indirect effects
by making it either easier or more difficult for clouds
to form, and for precipitation to fall. Aerosols can also
make both clouds and snow surfaces darker. Models are
currently based on the assumption that the cooling effect
from reflective particles is much larger than the warming
effect from absorption of sunlight by dark particles.
Scenarios of future concentrations of greenhouse gases
are based on dubious assumptions about the future.
These scenarios depend on other models of projected
growth of population, economies, and energy use. Some
projections are so dubious that MIT’s Dr. Richard Lindzen,
a lead author of one of the IPCC science reports, has
referred to them as “children’s exercises.” As researchers
Ian Castles, formerly the head of Australia’s national
office of statistics, and David Henderson of the Westminster
Business School and formerly the chief economist
of the OECD, point out, when estimating potential
future climate changes, IPCC’s modelers inappropriately
compared future estimates of GDP in terms of exchange
rates rather than purchasing power parity. This produces
GDP estimates that are significantly inflated, leading to
estimates of greenhouse-gas producing activity that are
similarly inflated. Castles observes that if such assumptions
are correct, then the average income of South Africans
will have overtaken that of Americans by a very
wide margin by the end of the century. Because of this
economic error, the IPCC scenarios of the future also
suggest that relatively poor developing countries such as
Algeria, Argentina, Libya, Turkey, and North Korea will
all surpass the United States.
Canada’s ratification of the Kyoto protocol, if it is treated
seriously and attempts are made to reduce Canada’s
greenhouse gas emissions by nearly 30% in the next few
years (the estimated reduction required of Canada), is
likely to have a major impact on the future of the Canadian
economy and the allocation of scarce environmental
resources. That ratification relied largely on frightening
scenarios generated by computer climate models that are
simply not sophisticated enough to serve as meaningful
guides to instituting public policy. Though politicians
such as Environment Minister David Anderson claim
that “the science is solid,” even a cursory inspection of
the many problems with computer climate models suggests
it is anything but.