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What You Won’t Find in the New National Climate Assessment
By Patrick J. Michaels of Cato.
"Under the U.S. Global Change Research Act of 1990, the federal
government has been charged with producing large National Climate
Assessments (NCA), and today the most recent iteration has arrived. It
is typical of these sorts of documents–much about how the future of
mankind is doomed to suffer through increasingly erratic weather and
other tribulations. It’s also missing a few tidbits of information that
convincingly argue that everything in it with regard to upcoming 21st century climate needs to be taken with a mountain of salt.
The projections in the NCA are all based upon climate models. If
there is something big that is systematically wrong with them, then the
projections aren’t worth making or believing.
Here’s the first bit of missing information:
The chart shows predicted and observed tropical (20⁰N-20⁰S)
temperatures in the middle of the earth’s active weather
zone—technically the mid-troposphere, roughly from 5,000ft to 30,000ft
elevation. The predicted values are from the 102 climate model
realizations from 32 different base model groups. These models are from
the most recent science compendium of the UN’s Intergovernmental Panel
on Climate Change (IPCC), and is the most comprehensive set available.
Data for the chart were recently published in the Bulleting of the American Meteorological Society.
The squares are the average of the three extant datasets for
satellite-sensed global temperatures in the same zone, the circles are
the average of the four weather balloon records, and the diamonds are
the fancy new “reanalysis” data, which uses a physical model to
compensate for the fact that not all three-dimensional “soundings” of
the atmosphere are from the same stations every day.
The difference between the predicted changes and observed is
striking, with only one model, the Russian INCM4, appearing realistic.
In its latest iteration, its climate sensitivity (the net warming
calculated for a doubling of the atmosphere’s carbon dioxide
concentration) is 1.4⁰C (2.5⁰F) compared to the average of 3.2⁰C (5.8⁰F)
in the family of models used in the National Climate Assessment. In
fact, the temperature trajectory the earth is on, along with an expected
large-scale shift from coal to gas for electrical generation (already
underway in the U.S. and Canada) will keep total human-caused warming to
less than 2.0⁰C (3.6⁰F) between 1950 and 2100, which is the goal of the
Paris Climate Agreement.1
That’s a far cry from the extremism of the National Assessment.
The second bit of missing information is sufficient to invalidate
most of the Assessment’s predictions. It’s a bit more complicated than
the first one.
The vertical axis is height (as measured by barometric pressure) and
the horizontal axis is temperature change, in degrees C per decade. The
solid green line is the observed average of our four sets of vertical
sounding data from balloons. You can see that the observed warming rate
at the surface (given as the “1000 hPa” on the left axis) is a bit above
0.1⁰C/decade, while the predicted value (1979-2016) is smidge below
0.2⁰C. In other words, in this region, which is extremely important to
global climate, almost twice as much warming is being predicted compared
to what is measured. This is figure S-2 in the recent Bulleting of the American Meteorological Society report on the climate of 2016.
But the situation gets truly horrific as one goes up in the
atmosphere. The models predict that there should have been a huge “hot
spot” over the entire tropics, which is a bit less than 40% of the
globe’s surface. Halfway up through the atmosphere (by pressure), or at
500 hPa, the predicted warming is also twice what is being observed, and
further up, the prediction is for seven times more warming than is being observed.
The importance of this is paramount. The vertical distribution of
temperature in the tropics is central to the formation of precipitation.
When the difference between the surface and the upper layers is large,
surface air is more buoyant, billowing upwards as the cumulonimbus cloud
of a heavy thunderstorm. When the difference is less, storm activity is
suppressed. As shown on the chart, the difference is supposed to be
becoming less and less, which would result in a general tendency for
tropical drying. In reality, the opposite is occurring over much of the
tropics, which should result in an increase in precipitation, rather than the decrease forecast by the climate models.
Missing the tropical hot spot provokes an additional cascade of
errors. A vast amount of the moisture that forms precipitation here
originates in the tropics. Getting that wrong trashes the precipitation
forecast, with additional downstream consequences, this time for
temperature.
When the sun shines over a wet surface, the vast majority of its
incoming energy is shunted towards the evaporation of water rather than
direct heating of the surface. This is why in the hottest month in
Manaus, Brazil, in the middle of the tropical rainforest and only three
degrees from the equator, high temperatures average only 91⁰F (not
appreciably different than humid Washington, DC’s 88⁰F). To appreciate
the effect of water on surface heating of land areas, high temperatures
in July in bone-dry Death Valley average 117⁰F.
Getting the surface temperature wrong will have additional
consequences for vegetation and agriculture. In general, a wetter U.S.
is one of bumper crops and good water supplies out west from winter
snows, hardly the picture painted in the National Assessment.
So this one, like its predecessors, suffers from a serious and
obvious flaws that are simply ignored. As first documented in our 2004
book Meltdown, the first Assessment used models that were worse than a table of random numbers when applied to 20th
century coterminous U.S. temperatures, and the chief scientist for the
report knew it and went ahead anyway! The last (third) one engendered
book-length filed public comments, all with our eye for climate humor, and the second one was so bad that we published an entire palimpsest, or mirror-image document.
Ignoring the massive and critical errors noted above—along with a
whole other emerging story on the arbitrary nature of the climate
models—is certainly going to lead for some to call for a re-examiation
of EPA’s “Endangerment Finding” from carbon dioxide, which is the basis
for regulation of greenhouse gases."
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