You may assume climate proxies,
such as ice cores, are only used
to collect approximate temperature
data for centuries before real time
thermometer measurements began
(late 1800s) ... and for CO2 level
estimates before accurate real time
CO2 measurements began
in the late 1950s.
In fact, climate proxy data
can be used
for recent decades too.
Northern Hemisphere climate proxy
evidence from tree-rings, bore holes,
pollen, etc., consistently fails to show
sharply rising temperatures after 1940.
One example:
In 2016, Dr. Pei Xing
and co-authors
unveiled a new method (MVDM)
for calibrating low-frequency
NH tree-ring data
for the last 1,200 years
in "The Extratropical Northern
Hemisphere Temperature
Reconstruction during the
Last Millennium Based
on a Novel Method."
Using 126 proxy temperature records
from the Northern Hemisphere,
they found a clearly visible
Medieval Warm Period (950-1150)
and Little Ice Age (1450-1850).
The smoothed MDVM reconstruction
also exhibited a general agreement
with reconstructed total solar irradiance,
or TSI.
But the Xing et al.
reconstruction
of Northern Hemisphere
temperatures
revealed no net warming
for the past 60 years,
following a 1930s and 1940s
temperature peak.
Many smarmy climate
proxy reconstructions
stop at 1980 or 1990,
and then splice on a
hockey-stick-shaped
rising surface temperatures
from thermometer records
from US-NASA, US-NAAO GISS,
or England-HadCRUT).
As a result, the recent decades
on the right side of their charts
show significant warming.
The purpose of splicing
two completely different
data sources on the same chart
is global warming propaganda:
-- Constructing a temperature chart
with an upward trend from left
(the old days) to right (today)
suggests dangerous warming ahead
... compared with a 100%
climate proxy chart that showed
no upward trend after 1940.
The most famous of these
smarmy spliced charts
is the now discredited
Michael Mann
"Hockey Stick Chart"
that Al Gore loved, and
probably still uses today
to scare people.
The multi-century
"Hockey Stick Chart"
didn't bother to mention
that tree ring data
showed no trend
for many centuries,
and then actually
showed cooling
in the past century
-- but the cooling period
was cut off, and replaced
by surface thermometer data,
that showed warming
in the past century !
Deceptions like that
are typical of
government
bureaucrat
"scientists".
The lack of recently
rising temperatures
in most climate
proxy evidence
is called the
“divergence problem”.
The “trick” of splicing on
surface thermometer data
for recent decades, even when
proxy data are available,
is called “Hiding the Decline”.
There were many
"Hide the Decline"
conversations found
in the hacked
"Climate Gate" eMails
in 2009 and 2011:
“…you really ought to replace
the values from 1961 onwards
with observed [instrumental]
temperatures due to the decline.”
“I’ve just completed Mike’s
(Michael Mann's) Nature trick
of adding in the real temps
to each series for the last 20 years
(ie; from 1981 onwards) and
from 1961 for Keith’s
to hide the decline.”
“Also we have applied
a completely artificial adjustment
to the data after 1960, so they
look closer to observed temperatures
than the tree-ring data actually were”
…. “Also, we set all post-1960 values
to missing in the MXD data set
(due to decline),
and the method will infill these,
estimating them from
the real temperatures
– another way of ‘correcting’
for the decline, though may be
not defensible!”
There is a large and
growing discrepancy
between the
surface thermometer
temperature data and
all other temperature data,
both real time data,
and climate proxy
reconstructions:
(1)
Data that show
little or no warming since 1940:
-- Most climate proxy studies
(2)
Data that show little or no warming
from late 1990s through 2018:
-- Weather Satellite data, and
-- Weather Balloon data
(3)
Data show significant warming
since 1980:
-- Surface thermometer data,
with measurements that sample
less than half of Earth's surface,
supplemented by wild guesses
to "infill" all other areas,
and there are also
requent arbitrary
"adjustments" of the
historical temperature data,
going back to the 1800s !
Given the data choices,
(1), (2) and (3),
only a smarmy
government bureaucrat
"scientist" would chose (3),
while completely ignoring
(1) and (2).
And that's exactly what they do !
I would ignore (3).
And I bet you would too.
The claim that rising CO2 levels
will cause runaway global warming,
that will end all life on Earth,
is a hoax based on absolutely
no scientific evidence.
There is absolutely
no scientific evidence
of runaway warming in
the past 4.5 billion years,
with CO2 levels
higher than today
almost the whole time
-- 10x to 15x higher
at the peak.
Claiming climate change
is an "existential threat",
is a propaganda tool used
to control and manipulate
stupid, gullible people.
Some people use that
propaganda to attack
capitalism, and promote
communism:
