Note:
The average climate model assumes
about +3 degree C. of warming
from a doubling of the CO2 level.
The actual warming rate since
1979, if all warming is arbitrarily
assumed to be caused by CO2
( an assumption, not a fact ! )
is about +1 degree C. per
doubling of the CO2 level
That's why climate computer
games, on average, predict
almost triple the global warming
that actually happens !
The models are obviously wrong,
predicting far too much warming.
Also wrong are estimates for
future growth of CO2 levels
in the atmosphere, used
for long-term CO2
assessment "studies".
The long-term
Climate Assessments
are really wild guesses
about the future climate.
They are a waste of time,
and money.
Predicting 25, 50 or 100 years
in the future is impossible
-- that's climate astrology.
Knowing that climate alarmists
grossly overstate the warming
effect of CO2, it should be
no surprise that long-term
climate assessments
grossly overstate the
the most likely growth rate
of atmospheric CO2 !
They typically assume
our atmosphere
will have rapid future
CO2 level growth,
much faster than
in recent decades !
The climate modeling
research community
( computer gamers )
have four CO2 level
growth estimates,
designated as
RCP2.6,
RCP4.5,
RCP6.0
RCP8.5.
RCP stands for
Representative
Concentration
Pathways.
RCP4.5 and RCP8.5
were used for
the Fourth National
Climate Assessment,
primarily RCP8.5:
“RCP8.5 implies
a future with continued
high emissions growth ... "
(Executive Summary, p.7).
RCP8.5 is implied to be
a “business as usual”
CO2 growth scenario.
But that's not true !
RCP8.5 abruptly deviates
from the historical trend,
to attain CO2 levels
of 936ppm in the year 2100.
The CO2 growth rate
would have to immediately
depart from the historical
growth pattern, towards
more than double of
any other forecast,
or RCP.
The acceleration of CO2 levels
for RCP8.5 should have started
many years ago,
but ongoing measurements
show it is not happening.
RCP8.5 is
a flawed projection
for the future, not a
“business as usual”
estimate.
RCP8.5 is
an energy-intensive
CO2 level growth
scenario as a result of
high population growth,
and a lower rate of
technology development.
Coal comprises nearly 50%
of RCP8.5’s energy mix,
something not seen since
early in the last century.
RCP8.5 has been called
a “return to coal” scenario !
-- The population projection
is at the high limit
of the United Nations'
always too high scenarios.
-- The primary energy
consumption projection is at
the 99th percentile probability,
through most of this century.
RCP8.5 is a compilation
of very low probability
assumptions yielding
a very unlikely, very high,
CO2 concentration
at the end of our century.
We have a 60-year record
of CO2 concentration
measurements.
CO2 concentrations in 2100
will likely fall in the 565-680 ppm
range, well short of the 936 ppm
indicated by RCP8.5.
The RCP8.5 estimate
would be a +6.5ppm / year
CO2 level increase
from 2019 to 2100.
The CO2 level is currently rising
at an annual rate of only +2ppm / year !
RCP8.5 was based
on low probabilities,
and questionable
assumptions
RCP8.5 is not
“business as usual”.
It assumes
the population
will be rising rapidly,
ignoring recent
low birth rates,
technological
progress
will stagnate,
and we'll start
using coal
for most of
our electricity
generation !
RCP8.5 is northing more
than a propaganda tool
for climate alarmism.