Australian  SPIN







January 2015



Commenters (aka "commentators") in the popular press tend to get facts about climate wrong. e.g. Paige Taylor in The Australian P5, 5th September 2016 thought that the last Ice Age ended just before Aboriginals built stone houses about 9,000 years ago.


I will not detail the negative effects that such (9C) cooling would have on the human race.  Suffice to say, it makes the warmist's concerns about a 3C rise look like a Sunday School picnic.

I hope for my grandchildren's sake that our efforts at causing global warming will serve to reduce that cooling.  Because I have the gut feeling that if something has happened for over 2 million  years with clockwork regularity, and if nobody has a credible explanation as to why it has been happening, then it is more likely than not that it is going to continue happening.



From geological, fossil and carbon dating evidence, scientists believe that the Earth has experienced at least four “Ice Ages” in it's 4.5 billion year existence.  We are currently in the fifth ice age.  Figure 1 is a graph from Wikipedia showing ice ages in colour.  I have created Table 1 below to provide details of ice age dates.


Figure 1

2,400 - 2,100 MYBC
850-635 MYBC
460-430 MYBC
360-260 MYBC
2.6 MYBC to now.

Table 1 Dates of the known ice ages.

The Cryogenian was reputedly the coldest ice age.  There is discussion among scientists as to whether glaciers reached the equator = "Snowball Earth" or perhaps that some oceans at the equator were still water = "Slushball Earth".  In between ice ages it is believed that there were periods when tropical conditions existed at the poles.

At the moment the average depth of ice on Antarctica is about 2,160 meters, spread over an area of 14 million square kilometers.  The area of the world's oceans is 360 million square kilometers.  So if all of the ice on Antarctica melted, the sea level would rise something less than 2,160 * 14 / 360 which is 84 meters.  NASA reports 83 billion tons of ice as melting each year (2014) from W Antarctica (the bit that is losing mass).  Ice weighs slightly less than 1 tonne per cubic meter.  So if we spread 80 billion (80 x 10^9) cubic meters of melted ice over 360 million square kilometers = 360 x 10^12 sq meters of ocean, the sea level would rise by: {Vol=Area x Height, so H=V/A} So H = (83 * 10^9) / (360*10^12) meters which is 2.3 * 10-4 meters which is less than 1/4 of a millimeter per annum, or about an inch per century.

Put another way, if the annual loss of ice from the Antarctic ice sheet was rained onto Queensland it would produce 5 mm (20 points) of rain which would not break the drought.


The current Ice Age started approximately 2,600,000 years ago.  Anthropologists agree, more or less, that is about when Homo Sapiens (aka Humans) first appeared on planet Earth.  Figure 2 from Wikipedia shows temperatures over the last five million years plotted as hotter or colder than the annual world's mean today, which is the dotted "zero" line near the top. 


Figure 2



In the last few decades scientists have drilled deep (3,190 meters) into ice lakes in Antarctica.  By analysis of the material of these "ice cores" they were able to determine relative temperatures and sea levels over the last 800,000 years.

Two of the studies are “EPICA” and Vostok”. From these ice cores scientists were able to determine that during the last 800,000 years of the current Ice Age there had been a sequence of glacial-interglacial events with a period of about 100,000 years. This periodicity over the last 500,000 years is illustrated on the extreme right hand side of Fig. 2 and in greater detail in Figs. 3, 4 & 5.

This sequence followed an earlier cycle of glacials/interglacials having a period of 46,000 years. (Shown in mid RHS of Fig. 2).

Typically during interglacial periods (i.e. right now, 2015AD) the average global temperature rises by 7C – 9C. (13F – 16F).

The Ice Core results are shown in Figures 3, 4 and 5.

Figure 3.

Variations in temperature, CO2, and dust from the Vostok ice core over the last 400,000 years


Figure 4

Showing how the EPICA cores confirmed the Vostok cores over 400,000 years.
  Note that “ice volume” (bottom of Fig 4) vertical ordinates are inverted. The amount of ice captured during the glacial periods is not trivial. The sea level was 110 meters (360 feet) below it's present value. The approximately 100,000 year period of interglacials over the last million years is shown in both the Epica and the Vostok cores.

Figure 5
A more extended view (800,000 years) of the EPICA results.



We are currently in the Holocene (interglacial) period of the Quaternary Ice Age.  The Holocene started about 10,000 – 12,000 years ago. (Figure 6). It is typical that the sea level rises during an interglacial period by around 110 meters or 360 feet. So over the last 2 million years the sea level was normally 110 meters lower than it is today.

Beside being colder, the weather during a glacial period is less turbulent and rainfall is greatly reduced.  Reduced rainfall on the few "temperate" zones that would presumably exist (having migrated into the tropics) would likely make Agriculture difficult.

It is not considered to be a coincidence that the earliest recorded instances of agriculture in Egypt, India, China & Mesopotamia are dated at around 10,000 – 12,000 years ago.  When the last cold period ended.

The next graph from Wikipedia shows a further contraction in the time scale from half a million years to 10,000 years.

Figure 6.

The black line is the average of 10 different studies.  It can be seen (Fig 5) that the temperature rose steeply by about 12C (22F) to our present day temperature over the previous 5,000 years.  It can be seen that the cooling trend (0.5C/8,000y) of the last 8,000 years has recently halted.  That warming is ascribed by some authorities to the fact that the CO2 concentration has risen from 0.028% to 0.04% in the last century.


The last two thousand years of temperature change is shown below in Fig. 7

Figure 7

From Wikipedia. Shows reconstructed proxy temperature studies from ten sources covering the last 2,000 years.  The data seem to illustrate that the industrial revolution (1760) coincided with the end of the "Little Ice Age" (or perhaps staved off the end of the Holocene interglacial period.)

Figure 8.

In the last few decades the planetary temperature has risen by about 0.5C. The evidence for planetary temperatures over the last 130 years as displayed by Fig. 8 is disputed.  There are recent challenges to the data "adjustment" procedures used by climate scientists who prepared the graph.



Computer models are not facts. No model predicted the recent warming (temperature) pause (2000-2013).  The current increase (2014 of 0.04C) is not convincing proof that warming has not paused. Models that show warming are not evidence that warming will occur. (I am reminded of a cousin who once told me “I have a program on my computer that exactly predicts the stock market up to today. After today, it is useless.”)

So far I have been unable to find a settled explanation as to why Ice ages happen or end, or why interglacial periods occur.  The consensus that does exist seems to be that it may be a mix of the following: (a) Atmospheric (CO2 & CH4) composition, (b) orbital changes, (c) Milankovitch cycles, (d) tectonic plates, (e) variations in solar output, (f) meteorites, (g) vulcanism. (h) something else.

The warmist website "" has published the Vostok data, (Top of Fig 3 above) and dismissed the idea that the current  10,000 years old interglacial is ending. They reason that "The cycle appears to be a response to changes in the Earth’s orbit and tilt" and continue:

  1. These two factors, orbit and tilt, are weak and are not acting within the same timescale – they are out of phase by about 10,000 years. This means that their combined effect would probably be too weak to trigger an ice age. You have to go back 430,000 years to find an interglacial with similar conditions, and this interglacial lasted about 30,000 years.
  2. The warming effect from CO2 and other greenhouse gases is greater than the cooling effect expected from natural factors. Without human interference, the Earth’s orbit and tilt, a slight decline in solar output since the 1950s and volcanic activity would have led to global cooling. Yet global temperatures are definitely on the rise.

Countering those points from skeptical:

  1. The explanation "orbit and tilt" are "out of phase" defies logic.  If two cycles are out of phase by 10,000 years, and need to coincide to produce or end an ice age, they do not coincide after 430,000 years.  It is also notable (Fig 3 & Fig 4) that the preceding interglacial periods were around 3C - 6C warmer than our current interglacial.
  2. The mere assertion that the warming effect of CO2 and other gases is greater than cooling from natural (read "unknown") historic sources relies on the assumed/calculated value of the constant in the Arrenhius equation*, which determines the Temperature Sensitivity to CO2 concentration. Other academics (Roy Spencer, University Alabama, Nicola Scafetta, U Naples) think the IPCC assumed value it is out by a factor of 2 or more.  Since the assumed value was based on selected values of Global temperature and CO2 before the current warming hiatus, perhaps it is time that the IPCC revised it's calculation of the temperature sensitivity constant.

Footnote. *  Arrhenius equation as modified for IPCC2001 is: dT = SConst * Ln(C/Co) where dT is Temperature change, and C/Co is the ratio of CO2 concentration, and SConst is the sensitivity.


Below I show in three cases how sensitivity could be calculated.  I obtained the Temperatures from Fig. 8 above, and obtained CO2 concentrations from

Case 1. Temperature rise 1910 to 1940 -0.6C to -0.1C  = 0.5C.  CO2 from 299.3 to 310.4 ppm.   SConst = 0.5/Ln(310.4/299.3) = 13.7
Case 2. Temperature rise 1940 to 1980 -0.1C to -0.05C = 0.05C.  CO2 from 310.4 to 338 ppm     SConst = 0.05/Ln(338/310.4) = 0.02
Case 3. Temperature rise 1880 to 2016 -0.3C to  -0.5C  = 0.8C.  CO2 from 289.8 to 400 ppm       SConst = 0.8/Ln(400/289.8) = 2.48

As can be seen, the choice of time period can have a huge effect on the calculation of sensitivity.

In Figure 9 below I have used the IPCC formula to calculate the temperature rise (dT) for future CO2 levels of 500 ppm  and 600 ppm starting from the present level of 400ppm using the IPCC formula with different "sensitivity" constants:
                    dT = Sensitivity * Ln(CO2/400)

dT = Sens.Const * Ln(CO2/400)
CO2 = 500ppm
CO2 = 600 ppm
Sensitivity Const. = 13.7
dT = 3.1C
dT = 5.6C
Sensitivity Const. = 2.48
dT = 0.56C
dT = 1.0C

Figure 9

Of course, other elements will serve to exacerbate or diminish warming.  This model assumes solar insolation remains constant.  It is predicted to fall due to predicted reduced sunspot activity.  In that case, the world might actually get colder.

(Note to self: Buy on wool futures)


Scientists do not agree on what causes the warming that causes interglacial periods, or the cooling that ends interglacial periods.  Consider:

So at the very least,'s certainty that the ice will not come back soon is open to dispute.

There is no evidence that the outcome of global warming is bad.  Very few warmists consider less than a 2C rise to be alarming.  Most warmists consider more than 5C rise would be catastrophic. They appear to ignore the fact that during the last interglacial period 100,000 years ago the temperature was 3-5 C above it's present value.

The main thrust of their alarm seems to be (a) Sea level rising, (b) inclement weather and (c) problems resulting from ocean acidification.

It is my belief that the cost of managing those problems is orders of magnitude less than the cost of reducing carbon use.  Most authorities now concede that a rise in CO2 is on balance beneficial to agriculture.


Our world is not well organised. The UNFAO estimates that 870 million people suffer from undernourishment, and UNWFP estimates that around 3 million children under 5 starve to death each year.  At the same time, rich greenies in their massive SUVs drive up the world price of grain by turning it into ethyl alcohol and using it as a substitute for gasoline.

Alternative energy supplies are subsidised by taxes on carbon energy. That makes electricity more expensive. Power being more expensive, the poorest and most vulnerable members of our society freeze in winter and roast in summer.

And those alternative energy supplies have their own problems. Wind farms produce infrasonic sound, which has tentatively been established as producing health problems.  (See peer reviewed report by Steven Cooper). Solar cells require rare earths, which produce extremely poisonous pollution in their production.

These evils are so unnecessary. As a Libertarian I believe that if Governments would keep out of the way, and stick to the job of taxing poisonous pollutants, technology would solve those problems.  In solar cell technology the price is falling and efficiency is rising at such a rate that already solar electricity can be produced for an amortised cost of 10 - 12 cents per KWH. All we need is an energy storage system. A recent article by Giles Parkinson reports that power storage costs should drop to $230/KWH by 2018. The author cites Citigroup, HSBC and UBS as having estimated that at that price, fossil fuels will go into “terminal decline”.

But no. It seems that no government in the world can resist a tax that can be promoted to the voters as a "moral imperative". And a carbon tax appears to fit that bill. Without one, we are told, our children will inherit a barren world.

But surely,” you say, “this proof of climate change is based on sound, peer reviewed scientific research by reputable scientists?” Again I cite the EPICA abstract from Nature:

"Given the similarities between this earlier warm period and today, our results may imply that without human intervention, a climate similar to the present one would extend well into the future."

Personally I do not consider that such a tentative conclusion by a body promoted as consisting of possibly the most authoritative group of climate scientists in the world can be used by governments to justify the levying of taxes equivalent to 2%** of Gross World Product.

According to the world factbook, world GDP (PPP basis) was $75 trillion in 2013.  So they recommend a tax of nearly $2 trillion per year, (growing with inflation..)


** a forever tax equivalent to 2% of world GDP would be required to stabilize CO2 at 0.05% according to Nicolas Stern, author of the Stern Review.