Anthropogenic Global Warming
Is Earth at the tipping point?
By: Geoffrey Pohanka
Objectives
Examine in a thorough, yet understandable way, the theory of
man made global warming
Analyze plausibility
Discuss what the primary driver of climate change is
Give a prediction of the global climate for the next 20 years
Observation
• Temperatures on earth have been rising
moderately….
• So there is some “ warming” ….from whatever cause.
But recent warming is not global
The warming is only in the Northern Hemisphere
(Source: David Archibald)
• Atmospheric temperatures have increased
about .2 degrees C since 1979 (using satellite
data)
• Despite this what do the supporters of the
man made global warming theory (AGW)
predict for the remaining years of the 21st
Century?
Supporters of AGW predict temperatures will rise as
much as 11.5 degrees Fahrenheit by 2100
Polar ice and glaciers will melt. The Arctic sea ice
could disappear completely within five years
Sea level will rise up to 20 feet by 2100
Hurricanes and their intensity will increase.
The rapidly changing climate will threaten
species with extinction
Resulting in millions of climate refugees
But will this happen?
Words of wisdom/Rules of the road
• Scientific Method……
Consists of theories and concepts that must be
proven through observation.
“Principles and procedures for the systematic pursuit
of knowledge involving the recognition and
formulation of a problem, the collection of data
through observation and experiment, and the
formulation and testing of hypotheses.”
(Wikipedia)
“No amount of experimentation can prove me
right, but a single experiment can prove me
wrong.”
Einstein
President Dwight D. Eisenhower gave two warnings in
his farewell address to the nation, regarding:
“The military industrial complex” (and also…..)
The “ domination of the nation’s scholars by Federal
employment, project allocations, and the power of money is
ever present – and is to be greatly regarded”…
“…we must be alert to….the danger that public policy itself
become captive of the scientific-technological elite”
Question: Is it warmer than it has ever been?
With the exception of the recent Ice Ages the Earth’s
temperature today is cooler than most of the last
sixty-five million years.
(chart reads right to left)
(source: James Zachos)
The earth has been in an ice age much of the last 400,000 years.
The earth’s temperature in each of the last four interglacial
periods was several degrees warmer than today.
(source: Vostok Ice Core, Law Ice Dome, Mauna Loa air sample)
We are in an 11,000 year interglacial period called the Holocene.
It has been warmer than today quite a few times in this period.
This warming is from natural causes and not man.
Temperatures were several degrees warmer than today in the Bronze Age,
the Roman Age, and the Medieval Period. The earth cooled several degrees
from 1400 to 1800, this period is called “The Little Ice Age”.
The Earth’s warming started in the early 1700s, long before CO2 was a factor.
U.S. has tracked continental temperatures since 1895
U.S. temperatures have been cooler in five of the last seven decades even
though CO2 levels increased in this period.
The forty year cooling period from the late 30’s to 70’s caused some
to fear the return of an ice age.
The 1970s cooling scare
Headline: January 1977
The ten warmest years in the U.S.
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•
•
•
•
•
•
•
•
•
•
•
1934
1998
1921
1906
1931
1999
1953
1990
1938
1939
Five of the ten warmest years in the USA were before 1940
The warmest decade in the USA was the 1930s
(Source: NASA GISS)
The year that the record high temperature was
recorded in each of the continents
•
•
•
•
•
•
•
•
1920 South America
1977 Europe
1960 Australia
1913 North America
1922 Africa
1933 Asia
1974 Antarctica
1960 Oceana
(Source: Wikipedia)
1885-2008 U.S. 50-State Record High Temperatures
Many were before 1955 (source: Hallofrecord.blogspot.com)
The U.S. has the longest and most comprehensive record of
temperature data from ground weather stations
(source: Climateskeptic.com)
Most parts of the globe do not keep consistent track of
the climate. This map shows weather stations reporting
data at least 67% of the time from 1978-2007
(Source: GHCN)
In the early 1990s climate data stopped being collected from thousands of
global weather stations. Many of these stations were in cooler rural areas
such as Siberia. Temperatures appeared to rise as the stations were dropped.
How temperature is collected impacts the data.
(source: Joe D’Aleo)
One way the U.S. tracks temperature is from 1,221 ground
weather stations.
These stations are supposed to be kept at a distance from
buildings, roadways, and trees
(Source: Anthony Watts)
(
Observation shows that many stations are poorly located next to
buildings and gravel roadways
Adjacent to buildings, cars, parking lots, satellite dishes, and air
conditioners
On hot rooftops
Next to trash burn barrels and tennis courts
Temperatures rose at this station
when the nearby tennis court was built
Adjacent to transformers, buildings, and dumpsters
Next to A/C condensors
Many weather stations are located at airports
In sewage treatment plants.
This one is next to a smoker’s urn
Some are in backyards and people’s “stuff”
Changes within close proximity to climate stations impacts the
temperatures that are recorded.
Some weather stations are near barbeque grills.
Burgers anyone?
In junkyards
These two stations are forty miles apart and show different
results due to the proximity of development.
This demonstrates the impact of land use changes on
‘local’ temperatures.
• Of the 1,221 U.S. ground weather stations 82% have been
independently surveyed.
• Anthony Watts has found that 89% of the stations checked are
poorly located and are within 100 feet of an artificial heat
source that causes a heat bias of 1 degree C to 5 degrees C
• These ground weather stations have been encroached by
development and thus show higher temperatures due to the
“heat island effect”
• Attempts are made to correct temperature readings as a
result of land use changes but…….by whom? And how?
Results of the 1,221 USCHN surface weather station quality
ratings
(Source: Anthony Watts)
Location of U.S. climate stations
and their ratings
Bias rating factor
URBAN HEAT ISLAND EFFECT
The world’s population has increased six-fold in the last 100 years.
The growing urbanization has caused “local” temperatures to rise.
(heat from the day is slower to dissipate at night in urban areas)
The chart below shows how the city of Reno Nevada
retains the heat of the day as one drives from the suburbs into the city.
(source: Anthony Watts)
The official EPA description of ‘heat islands’
(source: http://www.epa.gov/heatislands/index.htm)
• “the term "heat island
describes built up areas that
are hotter than nearby rural
areas. The annual mean air
temperature of a city with 1
million people or more can
be 1.8–5.4°F (1–3°C)
warmer than its
surroundings. In the
evening, the difference can
be as high as 22°F (12°C)”
As atmospheric CO2 levels increase how are temperatures reacting ?
U.S. temperatures in 2008 were below the 115 year average
U.S. 2009 Summer temperatures were the 34th coldest in 115 years.
U.S. October 2009 temperatures were the 3rd coldest ever for that month, 4 degrees
below normal. December 2009 temps were the 4th coldest ever for that month.
(Source: U.S. National Climate Data Center)
In February 2010 North America had the largest area of snow
cover ever recorded.
The Northern Hemisphere had the second largest ever.
(Source: Rutgers University Global Snow Lab)
Atmospheric temperatures do not have a bias from land use changes.
They show cooling since 2002
(satellite measurement of atmospheric temps began in 1979)
70% of the earth is ocean.
Argo (part of the inter global observation strategy) measures the
earth’s ocean temperature with over 3,000 buoys
(Source: ARGO)
Argo buoys dive 700 meters deep, surface, and then
send their temperature data to satellites
Argo has discovered that ocean temperatures
have not been warming but are somewhat cooler
(source: Dr. Craig Loehle, PhD)
This ocean cooling is contrary to climate model predictions
(source: John Willis, NASA, Craig Loehle, PhD)
Ocean surface temperatures are influenced by winds (El
Nino-La Nina). They also show a cooling trend.
No heat sinks have been discovered.
Let’s explore Carbon Dioxide
Atmospheric CO2 today is near the lowest level
in the last 540 million years
(Source: the Resilient Earth)
Three ice ages had more atmospheric CO2
than today’s level.
Ordovician-Silurian Ice Age - fifteen times more CO2
than today.
Cretaceous Ice Age - five times more.
Permian-Jurassic Ice Age - more CO2 than today as well.
Either CO2 does not cause much warming……natural forces are
much stronger…..or both.
(source: Ian Plimer)
CO2 is less than 4/10,000ths of the atmosphere
• CO2 is a trace gas, there is not much of it.
• There are 100,000 molecules in front of your face and
only 38 of them are CO2, (388 parts per million)
CO2 has grown 100ppm since the mid 1700s (+35%)
• CO2 as a percent of the atmosphere has grown
only 1/10,000th since the mid 1700s
(if you had ten cents in your pocket and it increases by 40%, the increase as a percentage is
large, but there is still not much of an overall impact caused by it)
Global temperatures are cooling even though
atmospheric CO2 concentrations are growing
(source: Univ of Alabama Huntsville, NOAA)
Greenhouse gases slow the release of heat from the
atmosphere. This is one reason why the earth’s
temperature is different from the Moon. Water vapor
comprises 95% of greenhouse gases.
(source: www.geocraft.com)
CO2 makes up 3.62% of greenhouse gases. But only 3.4% of
atmospheric CO2 comes from human sources, the rest is from
the oceans, decomposing vegetation and volcanoes. Thus man
made sources of CO2 are only responsible for 0.15%
of all greenhouse gases in the atmosphere.
(source: Heritage Foundation)
Question: How much warming can CO2 cause?
• Higher levels of CO2 do cause some warming.
However, CO2s ability to absorb heat is logarithmic,
meaning the more CO2 there is, the less heat it can absorb.
• If CO2 levels double or triple, CO2, by itself, can not cause
temperatures to rise more than 0.5 to 1.5 degrees C
• For CO2 to cause warming above 1.5 degrees Centigrade
rising levels of CO2 must cause positive feedbacks
Positive feedback, sometimes referred to as "cumulative
causation", refers to a situation where some effect causes more
of itself. A system undergoing positive feedback is unstable, that
is, it will tend to spiral out of control as the effect amplifies itself.
(Source: Wikipedia)
Rising levels of CO2 can only cause rising temperatures above
about 1 degree C if it also causes more water vapor in the
atmosphere/ heat trapping cirrus clouds/ or a reduction in
clouds.
But observation shows this does not happen.
Warming causes more low level clouds to form,
it rains and temperatures cool. Low level clouds are
negative feedbacks, they moderate temperature.
Cirrus Clouds slow the release of heat from the atmosphere.
Observation shows that fewer of these clouds form when air
temperatures warm.
C02’s absorption of heat is logarithmic, the more there is the
less heat it can absorb
(source: David Archibald)
The first 20ppm of CO2 absorbs more heat than the next 580ppm
(source: David Archibald)
Rising levels of CO2 have not had much impact on
temperature by themselves
(source: Richard Lindzen)
Rapid temperature change
is a daily, seasonal occurrence
• The difference between the daily low and high
temperature is about 20 degrees F
• Difference between record low and high Virginia
state temperatures is 140 degrees F
• Mankind and nature survived these radical
temperature changes, (they adapted)
Effect of CO2 on temperatures at two locations,
each at the same latitude
Dry desert
Humid jungle
The impact of humidity, H2O, and CO2 on
high/low temperatures
• The slight impact of warming from CO2 can be demonstrated from
the temperature changes between the low and high temperature in
humid tropical and dry desert areas
• Tropical areas are cooler in the day than the desert and are also
warmer at night, due to the stabilizing effect of humidity.
• In desert areas temperatures are both warmer in the day and
cooler in night than tropical areas.
• CO2 levels are about the same in both areas, yet the CO2 in the
desert does not trap/retain the heat of the day. This demonstrates
that CO2 by itself does not cause much warming and how
important water vapor is in stabilizing temperature.
The theory of AGW
• The theory of man made global warming states that increases in
atmospheric CO2 from man will absorb heat and cause temperatures to
rise. This warming from additional concentrations of CO2 is said to cause
increasing levels of humidity which in turn absorbs even more heat,
creating a vicious cycle with rising temperatures spinning out of control.
• If this theory is correct, why has runaway global warming not occurred in
earlier times, when atmospheric CO2 concentrations were much higher
than today’s?
• Temperatures and humidity also rise substantially in summer. This has not
triggered runaway temperatures, either.
Observation shows the theory of AGW to be false.
CO2 is essential for life on Earth
• CO2 levels were 270ppm in the mid 1700s
(they are 380ppm today).
• If CO2 levels fall below 200ppm, plants stop growing.
Photosynthesis stops.
• Most life on Earth was thus close to extinction
due to a lack of atmospheric CO2
Plants today grow 15% more quickly due to the higher level of
CO2.
Greenhouses raise CO2 levels to 1,000ppm to increase the
growth rate of plants.
Average growth enhancement due to a 300 PPM increase in atmospheric
CO2. Higher levels of CO2 can help feed a growing global population.
(source David Archibald)
+49%
+20%
+24%
+44%
+48 %
+37%
C3 cereals
C4 cereals
Fruits and melons
Legumes
Roots and tubers
vegetables
• With rising levels of atmospheric CO2:
 Plants require less water to grow.
 Arid areas of earth become
more productive agriculturally
Question: Is storm intensity increasing due to AGW?
U.S. tornado activity is in decline
(source: Plantsneedco2.org)
Global hurricane intensity is at 50 year lows
2009 US Hurricane activity is at 12 year lows
(source: Florida State University)
Global deaths due to extreme events is in decline
(source: appinys.org)
Question: Is the polar ice melting due to AGW?
• The earth is in an interglacial period. There is an imbalance
with the ice that remains at the poles from the last Ice Age
and the warmer temperature of the Holocene. Slow melting
has been going on for thousands of years and will continue.
• At the Poles, 20,000,000 square kilometers of sea ice melt and
then refreeze every year. As one pole melts the other freezes,
thus there is an offsetting balance
• Massive ice melt is natural and happens every single year
Both poles lose substantial amount of sea ice every
year in the polar Summer
• Question:
If the entire North Pole, all the Arctic ice melts, along
with all the sea ice on earth at both Poles……
How high would the seas rise?
Answer: None at All
Floating ice is already in the ocean, displacing water.
Melting sea ice cannot raise the sea level.
• For the seas to rise, ice on land must melt.
• Greenland has 10% of the land ice
• Antarctica has 90%.
• Question: In what year did Antarctica, with 90% of the
globe’s ice on land have the most sea ice ever recorded?
Answer:
2008
Antarctica had the most sea ice ever recorded in 2008
Antarctic sea ice has been growing almost continuously
for the last 30 years
(source: The Air Vent)
Satellite data shows Antarctic atmospheric temperatures are
cooling.
(Source: University of Alabama Huntsville)
There has been above average melting of the Arctic Summer
sea ice but an almost equal growth in the Antarctic sea ice, a
net 1.6% reduction according to Nasateam since 1979.
Total global sea ice volumes are remarkably stable.
The National Snow and Ice Data Center bootstrap method
shows a 177,000km increase in average global sea ice since
1979
In September 2009 the Arctic ice had grown 24% larger than two years
prior. The Antarctic ice was also one million sq kilometers larger than
the prior year. The Ice at both Poles is growing.
Wind and currents have large impacts on the ice. Unusual winds and
sea currents were responsible for much of the extra melting of the
Arctic sea ice. As these reversed the ice has begun to grow again.
Antarctica is the key to sea level rise
• Sea ice is greatly influenced by temperature, especially water temperature
• Sea ice has been growing in Antarctica for 30 years. Temperatures have
been cooling in 96% of Antarctica for 50 years (but not the Peninsula)
• The average temperature in Antarctic interior is -58 degrees F. It is also the
highest Continent on earth with an average altitude of 8,200 feet.
• Antarctic glaciers/ice sheets melt from the bottom up, not the top down
• Antarctica is classified as a desert. It is the driest place on earth. There is
little snow.
• If the man made global warming theory is true, sea ice will melt, but the
higher humidity will cause much more snow in the interior and overall ice
volumes will grow. This is also true of Greenland.
• Mankind has little impact on the climate in Antarctica
Scientific name for the Polar Bear is “Ursus Maritimus”, sea bear.
Polar Bears are excellent swimmers and can easily swim 100 miles or
more. The longest documented swim is 320 km.
Polar Bear populations are today the largest ever recorded, an
increase of 300%+ since the 1960s
Polar Bears have survived previous periods when the Arctic ice melted
completely
(source of polar bear population, US Senate)
The sea level has been rising for 20,000 years and the end of the
last Ice Age. The rate of increase has slowed, and especially in
the last four years
(source: Wikipedia)
Some say rising CO2 will cause
ocean acidification, killing corals
• If all the fossil fuels on earth were burned there would not be
enough CO2 to cause the oceans to acidify.
• CO2 in the ocean is converted to carbonate. It becomes fixed
in insoluble form, sinking to the ocean bottom.
• Coral reefs thrived when atmospheric CO2 was ten times
higher and temperatures ten degrees warmer than today.
•
Corals have adapted to changes in CO2 levels.
(Source: Ian Plimmer)
Why has the earth been warming if not from rising CO2
levels? The Sun may be the answer.
• Unless one lives in a geothermal or volcanic area the
source for the warm temperatures we have and need
to sustain life comes entirely from the Sun.
• The Earth’s greenhouse gases are the reason our
temperatures are not like those of the Moon, (-247
degrees F at night to +212 degrees F in day).
• Many climate scientists fail to look to the heavens to
take a closer view of the Sun.
(source: Wiki Answers)
Galileo was the first to observe Sunspots
Galileo’s drawing of sunspots in 1613
An active Sun on the left and inactive Sun on the right.
Sunspots are used to track solar activity. Solar activity is not constant,
the Sun has cycles that last an average of 11 years.
We are now in cycle 24.
Changing solar activity is measured by observing and counting Sunspots.
Note the variation of solar activity since 1610.
The observatory at Armagh Ireland has one of the longest
continuous temperature records on earth. This chart tracks the
close relationship between temperature (dots) from 1796 and 11
year solar cycles (solid line).
(source: Armagh Observatory)
The length of Sunspot cycles appears to be more closely linked
with temperatures than changing levels of CO2
(source: Friis-Christensen & Lassen . Dr. Tim Patterson)
The solar activity in the last years of the 20th Century was the
strongest in the last 8,000 years.
This may explain why global temperatures were warming in this
period
(Source: Joe D’Aleo)
Solar cycles average 11 years in length, half are shorter and half are
longer. When cycles are longer global temperatures cool and when
they are shorter, temperatures warm. There is no deviation over 400
years of observation
This shows how solar cycles are charted. A very active cycle was
predicted starting in 2008 but solar activity abruptly changed.
Solar activity today is at century lows.
Solar activity is driven by the Sun’s internal magnetic field.
It is measured using the AP Index.
The AP index is today at the lowest level ever recorded. Note that the
low AP index in mid chart was during the 1970s cooling scare.
(Source: David Archibald)
Solar cycle lengths from 1762. Cycle 23, which ended in 2009, is
the longest since 1788, a cycle that predated a several decade
long very cold period called the Dalton minimum
(Source: Wattsupwiththat.com)
Using temperature and solar records at De Bilt Netherlands
1705 - 2000, demonstrates the close relationship between
solar cycle length and temperatures.
With each additional year of cycle length above 11 years
temperatures cool an average of 0.7 degrees C.
(source: David Archibald)
The central England temperature record since 1659 shows the
same general relationship between solar cycle length in years
and temperature.
Using the record of temperature and solar cycle length at Hanover New
Hampshire since 1835 one can see that the short solar cycle 22 of the 1990’s
was during a warm period and the 12.5 year long cycle 23 will result in a 2.0
degree C reduction in temperature (3.6 deg F) at this location over the
expected twelve year life of solar cycle 24. This cooling has already begun.
(Source: David Archibald, using Friis-Christenson Larsen theory)
The years 2007, 2008, and 2009 have some of the lowest solar
activity since 1849. This might explain why global temperatures
have been cooling.
(Source: Anthony Watts)
Solar winds today are at the lowest level every recorded.
Changes in solar activity have impact on the atmosphere that
surrounds Earth.
Solar Impact on cloud formation
The impact on the earth’s climate from the Sun goes beyond irradiance (heat).
Solar winds have declined over 30% . Ultra violet radiation is down 6% to
8%. Cosmic rays reaching earth’s surface have also increased substantially.
Some scientists believe that changing solar activity affect global temperatures
by causing changes within the atmosphere and especially the clouds. With
today’s century low solar activity and record low solar winds it is thought
that the increase in cosmic rays that reach our atmosphere from deep in
space cause more clouds to form. Clouds reflect up to 65% of solar radiation
back into space and when there are more clouds temperatures cool.
Conversely, increasing solar activity and the resulting increase in solar winds
reduces the amount of cosmic rays that reach the atmosphere, fewer clouds
form, more solar rays reach the earth’s surface, and this leads to higher
temperatures.
If the past is a predictor of the future the changes we now see in solar activity
will cause the temperatures to cool for the next 20 years or longer. The
Thames River at London should regularly freeze once again as it often did
during the Little Ice Age and in the early 1800’s.
Relationship between cosmic rays and cloud formation.
Changes in solar cycles effect temperatures for the next
decade or longer.
(source: David Archibald)
The frozen Thames River at London in 1814 where Frost
Fairs were held. We should see this once again in the
coming years.
Frozen canals of the Netherlands, in stories by Hans
Christian Anderson
Conclusions
• The earth’s current warming trend started in the mid 1700s
with the end of the Little Ice Age
• Until we understand the natural forces that impact climate,
models cannot be relied upon to predict future temperatures
with accuracy
• CO2 does not have much direct impact on temperature
• Positive feedbacks caused by rising levels of CO2 have not
been observed
• Rising CO2 levels have a beneficial impact on plant growth
• There is little loss of overall global polar ice, though some
slow melting is normal. The melting of Arctic ice has no
impact on sea level
• Sea levels have been rising for thousands of years,
and some rise is normal
• Global hurricane intensity is at fifty year lows.
Conclusions
• Global temperatures have been cooling for eight years or
more.
• Polar bear populations are growing
• Solar activity and temperature are closely linked. Today’s
century low solar activity is causing temperatures to drop.
Temperatures could fall as quickly as the 70’s cooling scare but
they could become colder and last longer. This would cause
the loss of two weeks in the growing season on both ends (*)
and result in significantly reduced crop production.
• Cold periods are much worse for humanity than warm ones.
Cold periods in the past have been ones of famine, disease
and political instability
• Man has little impact on global temperatures
(* David Archibald)
• For more information
• www.isthereglobalwarming.com
• www.wattsupwiththat.com
• www.icecap.us
• Contact author
Geoffrey Pohanka
2120 Polo Pointe Dr
Vienna, VA 22181
gpohanka@pohanka.com