d) Carbon Cycle
In
their
scenarios
the
IPCC
emanates
from
the
assumption,
that
the
actually
observed
CO
2
increase
is
almost
exclusively
determined
by
anthropogenic
emissions
(AR5
[1]),
whereas
natu
-
ral
emissions
are
considered
to
be
independent
of
any
solar
or
tem
perature
variations,
this
in
contradiction
to
paleoclimatic
ice-core
data,
which
show
a
delay
of
the
CO
2
emission
to
the
temperature
of
about
800
years
(Petit
et
al.
1999
[2]),
and
this
also
in
dis
crepancy
to
actual
observations
with
a
delay
of
about
9
months
(McRae
2008
[3];
Humlum
et
al.
2013
[4];
Salby
2013 [5]; Salby 2016 [6]; Salby 2018 [7]).
The
emissions
of
CO
2
to
the
atmosphere
and
their
uptake
by
extraneous
reservoirs
are
consi
dered
in
more
or
less
refined
theoretical
models,
which
are
used
to
replicate
the
carbon
cycle.
From
these
models
climate
scientists
presume
that
this
cycle
has
come
out
of
balance
due
to
the
increasing
human
emissions
from
fossil
fuel
combustion
and
land
use
change.
Although
all
anthropogenic
emissions
over
the
Industrial
Era
are
not
more
than
1%
of
the
total
emissions
and
uptake
over
this
pe
riod
-
actu
al
ly
they
contribute
4.3
%
to
the
CO
2
emis
sions
per
year
-
the
IPCC
assumes
that
the
uptake
is
already
limited
and
about
half
of
it,
the
so
called
air
borne
fraction,
cumu
-
lates in the atmosphere.
This
is
made
responsible
for
the
rapidly
ri
-
sing
atmospheric
CO
2
concentration,
which
in
1850
was
about
280
ppm
and
over
the
Indu
strial
Era
increased
up
to
390
ppm
in
2012 (average over 10 years from 2007-2016: 393 ppm).
The
IPCC
further
assumes
that
the
removal
of
human-emitted
CO
2
from
the
atmosphere
by
natural
processes
will
take
up
to
a
few
hundred
thousand
years,
even
when
anthropogenic
emissions could completely be stopped.
As
the
rising
CO
2
concentrations
go
along
with
an
increasing
greenhouse
effect
and,
thus,
a
further
global
warming,
a
better
understanding
of
the
carbon
cycle
is
a
necessary
prerequisite
for all future climate change predictions.
1. Order Absorption
Different
to
the
IPCC's
accounting
scheme
we
emanate
from
a
carbon
cycle,
which
shows
no
saturation
in
the
uptake,
in
agreement
with
observations,
but
the
absorption
is
consi
-
dered
as
a
first
order
process,
scaling
pro
-
portional
with
the
actual
CO
2
concentration
in
the
atmos
phere
(Harde
2017
[8],
Harde
2019 [9]).
This
approach
is
well
justified
for
natural
ab
-
sorption
or
decay
processes,
and
it
is
sup
-
por
ted
by
the
observation
of
a
pure
expo
-
nential
decline
of
the
14
C-isotope
in
the
atmosphere after the stop of nuclear bomb tests in 1964.
With
this
modification
we
find
a
CO
2
resi
dence
time
of
not
more
than
4
years,
which
is
also
in
good agreement with the observed
14
C-decay time.
The
natural
emissions
then
contribute
96%
and
the
human
emissions
only
4%
to
the
total
concen
-
tration in agreement with the respective emission rates
.
Temperature Dependence
We
explain
the
stronger
increasing
concentration
over
the
Industrial
Era
from
280
to
390
ppm
mostly
by
a
temperature
dependent
resi
-
den
ce
time
and
a
T-dependent
natural
emission rate.
This
is
in
contradiction
to
the
IPCC,
which
exclusively
traces
the
ascending
CO
2
level
back
to
the
accumulating
anthropogenic
emissions
and
denies
any
larger
natural
va
-
riations,
although
paleoclimatic
and
also
ac
-
tual
investigations
show
significant
changes
of the CO
2
concentration with temperature.
Comparison with Observations
Our
approach
reproduces
the
concentrations
at
glacial
and
interglacial
times
as
well
as
the
slightly
exponential
increase
with
the
onset
of the Industrial Revolution.
Comparison
of
the
direct
CO
2
measurement
at
Mauna
Loa
with
a
simulation,
which
uses
respective
air
temperature
data
of
Hawaii
to
gether
with
the
anthropogenic
emissions
over
recent
years,
documents
this
excellent
agreement
(Harde
2019
[9]).
From
this
analy
sis
we
deduce
that
for
the
113
ppm
CO
2
in
crease
over
the
Industrial
Era
human
emis
sions were only donating about 15 %.
Recent
studies
of
the
absorption
time
of
atmospheric
CO
2
even
suggest
a
still
lower
anthropo
-
genic
contribution
(Harde&Salby
2021
[10];
Salby&Harde
2021
[11,12];
Salby&Harde
2022
[13];
Harde 2023a [14]; Harde 2023b [15]).
Consequences
Thus,
not
anthropogenic
emissions
but
mainly
natural
processes,
in
particular
the
tempera
-
ture,
have
to
be
considered
as
the
dominating
impacts
for
the
observed
CO
2
increase
over
the
last 270 yr and also over paleoclimate periods.
With
these
anthropogenic
emissions
of
15
%
and
a
quota
of
30
%
caused
by
CO
2
to
global
warming
(Harde
2017
[16],
Harde
2018
[17],
Harde
2022
[18])
the
human
contribution
to
the
increased
tempe
rature
of
about
0.9°C
over
the
last
century
could
not
have
been
more
than
5%
or 0.05°C
.
This
completely
negligible
contribution
by
no
means
justifies
any
intended
reduction
of
fossil
fuels, only prospective resource protection can be discussed.
Instead,
political
delusion
destroys
a
prospering
industry
and
burdens
future
generations
with
additional debts of unprecedented dimensions.
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