NASA has conceded
that climate models
lack the precision
to make
climate predictions,
due to the inability
to accurately
model clouds.
Cloud cover
dominates
longwave radiation,
dwarfing the CO2
climate influence.
According to Wong
and Minnett (2018):
At the ocean surface,
clouds generate a
radiative signal
8 times greater
than tripled CO2
(1120 ppm).
CO2 can only
have an effect
on the first 0.01 mm
of the ocean.
Cloud
longwave forcing
penetrates
9 times deeper,
about 0.09 mm.
Cloud cover
modulates
the amount
of solar radiation
that warms the ocean.
When cloud cover
increases, less
shortwave radiation
reaches the surface,
leading to cooling.
When cloud cover
decreases, as it has
since the 1980s,
more solar radiation
is absorbed.
The decrease
in cloud cover
in recent decades
can therefore explain
the 1979-2017 warming
(Herman et al., 2013,
Poprovsky, 2019,
Loeb et al., 2018).
IPCC and NASA
admit that they
can’t model clouds
with much accuracy.
The IPCC has
admitted there is
a great deal of
“continuing uncertainty”
in the sign
and magnitude
of the cloud influence.
Most models indicate
a positive feedback
(more warming),
but this
“is not well understood”
and the IPCC scientists
“are not confident
that it is realistic.”
NASA has said some clouds
“cool more than they heat”
and other clouds
“warm more than they cool.”
In some models
“clouds decrease the
net greenhouse effect,
whereas in others
they intensify it.”
NASA concludes that
“today’s models
must be improved
by about a hundredfold
in accuracy”
if we wish to make
climate projections.
Uncertainty
in the effects
of cloud forcing are
20-40 times larger
than the projected
greenhouse gas
warming for the
next century
For IPCC’s
emission scenarios,
the projected
greenhouse gas
induced warming
by 2100 is +3.7°C.
Due to cloud
forcing errors,
the uncertainty
in this projection
is ±130°C. !
“When both
the cloud and the
forcing uncertainties
are allowed to
accumulate together,
after 5 years the A2
[greenhouse gas-induced]
scenario includes
a +0.34°C warmer Earth
but a ±8.8°C uncertainty.
At 10 years
this becomes
+0.44±15° C,
and 0.6±27.7°C
in 20 years.
By 2100,
the projection
is 3.7±130°C.”
Until we can model clouds,
we cannot model the future
climate with any precision.
But never mind all that --
"the science is settled" !