Earth’s history
includes many
major ice ages,
-- 10 in the past
one million years,
and another 10
in the
one million years
before that.
Each major
"glaciation"
lasts about
90,000 years,
followed by a
10,000-year
"interglacial".
We are currently in
an interglacial period,
called the Holocene.
Some scientists claim
the interglacial
we're now living in,
is the warmest period
of the past millennium.
“Unprecedented”
is often claimed.
Those are lies !
Glaciers began to form
over Antarctica
30 million years ago
and in the
Northern Hemisphere
3 million years ago.
Today we are
actually experiencing
one of
the coldest climates
in the
4.5 billion year history
of our planet !
Antarctic ice cores,
over the past
800,000 years,
reflect cycles of
major glaciation,
followed by
interglacial periods,
in 100,000 year-cycles.
These
Milankovitch cycles
are very likely
caused by the
eccentricity
of Earth’s orbit,
and its axial tilt.
Milankovitch cycles
are a set of
cyclic variations
in characteristics
of the Earth's orbit
around the Sun.
Each cycle
has a different length,
so at some times
their effects
reinforce each other,
and at other times
they (partially) cancel
each other.
There is strong evidence
that Milankovitch cycles
affect the occurrence
of glacial and interglacial
periods within an ice age.
That planetary
geometry cycle
is much more likely
to cause a change
in temperature,
than a change in CO2.
We have
high-quality
reconstructed
temperature
records
for the prior
four interglacials --
and all of them
were WARMER
than the current
interglacial !
The Russian
Vostok drilling station,
in East Antarctica,
provided a
420,000-year history
of Earth’s near-surface
air temperature and
atmospheric CO2
concentration.
This record covers
the current
interglacial period,
and the prior four
interglacials.
The current interglacial
is the COLDEST
of the five most recent
interglacials !
The four interglacials
before the current
Holocene interglacial,
averaged +2° C. warmer,
in spite of CO2 levels
below 300 ppm, compared
with about 410 ppm today.
The only thing
that's unusual
about today's
air temperature,
is that it is so low (cool)
in spite of such a high
CO2 concentration.
Similar findings
have been obtained
from the Dome Fuji
ice core, located
about 1,500 km
from the Vostok
ice core site.
That independent proxy
temperature record
reveals that the
past three interglacials
were much warmer,
by +4.5 to +6.0 degrees C.,
than the most recent
1,000 years .
Prior interglacial warmth,
+1 to +4 degrees C.
warmer than today,
was found in
a 550,000-year
sea surface temperature
dataset derived by
Herbert et al. (2001)
from marine
sediment cores,
from the western coast
of North America,
from around 22°N latitude,
at the southern tip
of the Baja Peninsula,
to around 42°N latitude
off the coast of Oregon.
Herbert, T.D., Schuffert, J.D., Andreasen, D.,
Heusser, L., Lyle, M., Mix, A., Ravelo, A.C.,
Stott, L.D., and Herguera, J.C.
2001.
Collapse of the California Current
during glacial maxima
linked to climate change on land.
Science 293: 71– 76.
These climate
proxy studies
ALL suggest
that Earth’s
current temperature
does NOT reflect
unusual warmth !
The IPCC’s claim
of a strong
human influence
on today’s climate
is primarily based
on their false claim
that Earth’s
current temperature
is unusually warm !
The ice core studies
also showed
Earth’s air temperature
rose 400 to 2,800 years
BEFORE any increase
in atmospheric CO2.
Increases in
atmospheric CO2
did NOT trigger
any of the major
global warmings
that ended
the past three
ice ages !
So carbon dioxide
was NOT
the primary cause
of the major
glacial-interglacial
temperature changes.
In fact,
the CO2 content
of the air
gradually ROSE
after the termination
of the last
great ice age,
by approximately
25 ppm,
between 8,200 BC
and 1,200 AD,
while global
air temperature
DECLINED !
Interglacials
also appear to have
a more stable climate
than cooler glacial periods.
Antarctic ice core data
suggest the current
CO2 concentration
is 40% higher
than at any time
in the past
650,000 years.
And the current
methane concentration
is approximately
130% percent higher.
If the IPCC
was correct
in attributing
a huge greenhouse
warming effect
to these two
greenhouse gases,
then Earth
should now have
a MUCH WARMER
temperature
than in the prior
interglacial periods.
But this has
NOT happened !