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The Skeptic's Case By Dr. David M.W. Evans
We check the main predictions of the climate models against the best and latest data. Fortunately
the climate models got all their major predictions wrong. Why? Every serious skeptical scientist
has been consistently saying essentially the same thing for over 20 years, yet most people
have never heard the message. Here it is, put simply enough for any lay reader willing
to pay attention.
What the Government Climate Scientists Say
The direct effect of CO2 is well-established physics, based on laboratory results, and
known for over a century.
Feedbacks are due to the ways the Earth reacts to the direct warming effect of the CO2. The
threefold amplification by feedbacks is based on the assumption, or guess, made around 1980,
that more warming due to CO2 will cause more evaporation from the oceans and that this
extra water vapor will in turn lead to even more heat trapping because water vapor is
the main greenhouse gas. And extra heat will cause even more evaporation, and so on. This
amplification is built into all the climate models. The amount of amplification is estimated
by assuming that nearly all the industrial-age warming is due to our CO2.
The government climate scientists and the media often tell us about the direct effect
of the CO2, but rarely admit that two-thirds of their projected temperature increases are
due to amplification by feedbacks.
What the Skeptics Say
The serious skeptical scientists have always agreed with the government climate scientists
about the direct effect of CO2. The argument is entirely about the feedbacks.
The feedbacks dampen or reduce the direct effect of the extra CO2, cutting it roughly
in half. The main feedbacks involve evaporation, water vapor, and clouds. In particular, water
vapor condenses into clouds, so extra water vapor due to the direct warming effect of
extra CO2 will cause extra clouds, which reflect sunlight back out into space and cool the
earth, thereby reducing the overall warming.
There are literally thousands of feedbacks, each of which either reinforces or opposes
the direct-warming effect of the extra CO2. Almost every long-lived system is governed
by net feedback that dampens its response to a perturbation. If a system instead reacts
to a perturbation by amplifying it, the system is likely to reach a tipping point and become
unstable (like the electronic squeal that erupts when a microphone gets too close to
its speakers). The Earth's climate is long-lived and stable — it has never gone into runaway
greenhouse, unlike Venus — which strongly suggests that the feedbacks dampen temperature
perturbations such as that from extra CO2.
What the Data Says
The climate models have been essentially the same for 30 years now, maintaining roughly
the same sensitivity to extra CO2 even while they got more detailed with more computer
power.
· How well have the climate models predicted the temperature?
· Does the data better support the climate models or the skeptic's view?
Air Temperatures
One of the earliest and most important predictions was presented to the US Congress in 1988 by
Dr James Hansen, the "father of global warming":
Hansen's predictions to the US Congress in 1988, compared to the subsequent temperatures
as measured by NASA satellites. Hansen's climate model clearly exaggerated
future temperature rises.
In particular, his climate model predicted that if human CO2 emissions were cut back
drastically starting in 1988, such that by the year 2000 the CO2 level was not rising
at all, we would get his scenario C. But in reality the temperature did not even rise
this much, even though our CO2 emissions strongly increased — which suggests that the climate
models greatly overestimate the effect of CO2 emissions.
A more considered prediction by the climate models was made in 1990 in the IPCC's First
Assessment Report:
It's 20 years now, and the average rate of increase in reality is below the lowest trend
in the range predicted by the IPCC.
Ocean Temperatures
The oceans hold the vast bulk of the heat in the climate system. We've only been measuring
ocean temperature properly since mid-2003, when the Argo system became operational. In
Argo, a buoy duck dives down to a depth of 2,000 meters, measures temperatures as it
very slowly ascends, then radios the results back to headquarters via satellite. Over 3,000
Argo buoys constantly patrol all the oceans of the world.
The ocean temperature has been basically flat since we started measuring it properly, and
not warming as quickly as the climate models predict.
Atmospheric Hotspot
The climate models predict a particular pattern of atmospheric warming during periods of global
warming; the most prominent change they predict is a warming in the tropics about 10 km up,
the "hotspot."
The hotspot is the sign of the amplification in their theory. The theory says the hotspot
is caused by extra evaporation, and by extra water vapor pushing the warmer, wetter lower
troposphere up into volume previously occupied by cool dry air. The presence of a hotspot
would indicate amplification is occurring, and vice versa.
We have been measuring atmospheric temperatures with weather balloons since the 1960s. Millions
of weather balloons have built up a good picture of atmospheric temperatures over the last
few decades, including the warming period from the late 1970s to the late '90s. This
important and pivotal data was not released publicly by the climate establishment until
2006, and then in an obscure place. Here it is:
On the left is the data collected by millions of weather balloons. On the right is what
the climate models say was happening. The theory (as per the climate models) is incompatible
with the observations. In both diagrams, the horizontal axis shows latitude, and the right
vertical axis shows height in kilometers. In reality there was no hotspot, not even
a small one. So in reality there is no amplification — the amplification shown in figure 1 does
not exist.
Outgoing Radiation
The climate models predict that when the surface of the earth warms, less heat is radiated
from the earth into space (on a weekly or monthly time scale). This is because, according
to the theory, the warmer surface causes more evaporation and thus there is more heat-trapping
water vapor. This is the heat-trapping mechanism that is responsible for the assumed amplification
in figure 1.
Satellites have been measuring the radiation emitted from the earth for the last two decades.
A major study has linked the changes in temperature on the earth's surface with the changes in
the outgoing radiation. Here are the results:
Outgoing radiation from earth (vertical axis) against sea-surface temperature (horizontal),
as measured by the ERBE satellites (upper-left graph) and as "predicted" by 11 climate models
(the other graphs). Notice that the slopes of the graphs for the climate models are opposite
to the slope of the graph for the observed data.
This shows that in reality the earth gives off more heat when its surface is warmer.
This is the opposite of what the climate models predict. This shows that the climate models
trap heat too aggressively, and that their assumed amplification shown in figure 1 does
not exist.
Conclusions
All the data here is impeccably sourced — satellites, Argo, and weather balloons.
The air and ocean temperature data shows that the climate models overestimate temperature
rises. The climate establishment suggest that cooling due to undetected aerosols might be
responsible for the failure of the models to date, but this excuse is wearing thin — it
continues not to warm as much as they said it would, or in the way they said it would.
On the other hand, the rise in air temperature has been greater than the skeptics say could
be due to CO2. The skeptic's excuse is that the rise is mainly due to other forces — and
they point out that the world has been in a fairly steady warming trend of 0.5°C per
century since 1680 (with alternating ~30 year periods of warming and mild cooling) whereas
the vast bulk of all human CO2 emissions have been after 1945.
We've checked all the main predictions of the climate models against the best data:
Test Air temperatures from 1988
Climate Models - Overestimated rise, even if CO2 is drastically cut
Air temperatures from 1990 Climate Models - Overestimated trend rise
Ocean temperatures from 2003 Climate Models - Overestimated trend rise
greatly
Atmospheric hotspot Climate Models - Completely missing, therefore
no amplification
Outgoing radiation Climate Models - Opposite to reality, therefore
no amplification
The climate models get them all wrong. The missing hotspot and outgoing radiation data
both, independently, prove that the amplification in the climate models is not present. Without
the amplification, the climate model temperature predictions would be cut by at least two-thirds,
which would explain why they overestimated the recent air and ocean temperature increases.
Therefore,
1. The climate models are fundamentally flawed. Their assumed threefold amplification by feedbacks
does not in fact exist.
2. The climate models overestimate temperature rises due to CO2 by at least a factor of three.
The skeptical view is compatible with the data.
Some Political Points
The data presented here is impeccably sourced, very relevant, publicly available, and from
our best instruments. Yet it never appears in the mainstream media — have you ever
seen anything like any of the figures here in the mainstream media? That alone tells
you that the "debate" is about politics and power, and not about science or truth.
This is an unusual political issue, because there is a right and a wrong answer, and everyone
will know which it is eventually. People are going ahead and emitting CO2 anyway, so we
are doing the experiment: either the world heats up by several degrees by 2050 or so,
or it doesn't.
Notice that the skeptics agree with the government climate scientists about the direct effect
of CO2; they just disagree about the feedbacks. The climate debate is all about the feedbacks;
everything else is merely a sideshow. Yet hardly anyone knows that. The government climate
scientists and the mainstream media have framed the debate in terms of the direct effect of
CO2 and sideshows such as arctic ice, bad weather, or psychology. They almost never
mention the feedbacks. Why is that? Who has the power to make that happen?
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Climate Change in 12 Minutes - The Skeptic's Case

2880 分類 收藏
Jou 發佈於 2015 年 4 月 1 日
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