to the Australian Institute for International Affairs, Vic, 14 April, 2016
Dangerous Global Warming - Fact or Fiction? The Limits of the Paris Accord
|Des Moore: Source IPE|
My thesis today is that, despite the continued claims reported in the media, there is minimal risk that continued usage of fossil fuels will produce temperatures which become dangerously high. There is therefore no sound basis for governments to continue with expensive policies aimed at reducing usage of coal and other fossil fuels, which are by far the cheapest energy source. The so-called precautionary motive is not applicable now and is in fact less relevant than it was a few years ago.
Historically, there have been many examples of doom and gloom which did not eventuate. These include economist Jevons’s 1865 book expressing concern that excessive usage of coal was threatening to exhaust coal supplies and stop economic growth. This followed the thesis promulgated by Malthus in 1800 that population growth must be stopped and was again utilized in 1968 by US ecologist and demographer Dr Paul Ehrlich. Then in 1972 a large number of eminent scientists, including five fellows of the Royal Society, supported Ehrlich. In the same year the Club of Rome group predicted that, without government intervention, growth would stop within 100 years and population and industry would fall. For some time we have also had the Intergovernmental Panel on Climate Change or IPCC predicting dangerous temperatures unless we stop using fossil fuels.
By contrast, the 2007 book Scared to Death by Christopher Booker and Richard North not only rejected the dangerous warming thesis but outlined numerous other projects proposed by scientists and wrongly adopted by governments. Increasing numbers of organisations and individuals both here and overseas have also expressed sceptical global warming views in books and articles, including a petition by over 30,000 scientists in the US. My talk today draws particularly on research and advice by physicist Tom Quirk and meteorologist Bill Kininmonth former head of Australia’s National Climate Centre. There is no consensus that “science” justifies stopping the use of fossil fuels.
My own experience over the 28 years I worked in Federal Treasury is that professional scientists and economists often seek government action or funding to prevent wrongly perceived looming problems. When in 1972 I was temporarily researching at the Royal College of Defence Studies in London, I was given an “excellent” award for my analysis of the deficiencies in theses supporting Limits on the Supply of Resources. When in Treasury, I authored a publication on the serious deficiencies in proposals made through United Nations agencies for governments to establish a new international economic order to help low income countries. The NIEO is no longer pursued.
However, almost all governments and United Nations agencies still accept the dangerous warming thesis and, through the IPCC, have tried for over 30 years to reach agreement on action to prevent temperatures increasing by more than 2ºC since the 19th century. Not only have they failed, temperatures have also failed to increase over the past 17 years. This has given sceptical views some recognition.
I want now to consider some deficiencies in the dangerous warming thesis. I do so not as a scientist but as an economist with experience in recognizing claims which exhibit many uncertainties. You don’t have to be a scientist to find mistakes in assessments made by scientists.
The Theoretical Explanation Fails to Acknowledge Important Uncertainties
The dangerous warming thesis derives from the fact that a proportion of emissions of carbon dioxide from usage of fossil fuels remains in the atmosphere. What happens to it there?
The CO2 in the atmosphere is open to heating from the surface of the earth which is itself open to being heated from the sun’s radiation. Some of this heating of the CO2 in the atmosphere is in turn radiated back to the surface and increases the surface temperature as though in a greenhouse. Hence, warmist believers argue, the apparent increase in global average temperatures of about 0.7ºC over the past century is predominantly caused by this so-called greenhouse effect. This is argued to eventually raise temperatures to levels threatening human existence unless usage of fossil fuels stops.
One problem with this thesis is that the heat radiated back to earth from the CO2 in the atmosphere is offset by evaporation which absorbs heat and thus reduces the “greenhouse” effect. Expert opinions differ about the evaporation reduction effect but it is widely accepted as significant.
Let me over simplify the main aspects of the warming process
- Some of CO2 from fossil fuels stays in the atmosphere and is an addition to it;
- That remaining CO2 is exposed to heating from the earth’s surface which is itself heated by the sun;
- This heated CO2 also radiates back towards the earth’s surface;
- However some of the radiation back to the earth’s surface is subject to evaporation;
- There is dispute over the net effect on temperatures.
Another problem with interpreting the greenhouse theory is that it is based on research made many years ago suggesting that 55 per cent of emissions from fossil fuel usage stay in the atmosphere. But recent research suggests that only 16 per cent may be staying in the atmosphere. Much lower concentrations would of course have much smaller upwards effects on temperatures.
What Has Happened to Temperatures and Fossil Fuel Emissions (Figure 1)
Figure 1 compares what has happened to atmospheric CO2 concentrations and global surface temperatures since 1900. The temperatures, which are those used by the IPCC, are shown by the purple squares line. The CO2 concentrations are shown by the brownish circles, with the continuous line marking the periods of the Pacific Decadal Oscillation. This PDO reflected natural influences on temperatures arising from the replacement of cold water along the western Pacific coast of the North Americas and obviously had no causal connection with fossil fuel emissions.
What picture emerges from this over the period since 1920?
First, CO2 concentrations increased by 30 per cent as growth in world economies brought strong increases in emissions from fossil fuel usage. But average global temperatures increased by only about 7 per cent, with a rise from 14.7 to 15.8ºC
|Figure 1: CO2 measurements at the South Pole from ice cores and direct measurements and average global |
temperatures as published by HadCrut4 and used by the IPCC .The continuous line from 1920 marks the
periods of the Pacific Decadal Oscillation.
In short, temperature levels have increased much less than the increase in CO2 concentrations. A comparison of the two time series clearly indicates that there is no correlation between changes in the two. This comparison is summarised in Table 1.
Table 1: Variations in temperature and atmospheric CO2
Pacific Decadal Oscillation Phase
0C increase per 10 years
CO2 at the South Pole
Annual increase in ppm
1922 - 1947
0.13 +/- 0.02
0.40 +/- 0.03
1948 - 1976
-0.02 +/- 0.03
0.85 +/- 0.03
1977 - 2000
0.16 +/- 0.03
1.49 +/- 0.01
2001 - 2015
0.08 +/- 0.04
2.01 +/- 0.02
What this shows is that there were two periods, one from 1948 to 1977 and one from 2000 to the present, during which temperatures were relatively stable even though CO2 concentration levels increased quite strongly (except for the 1940-50 period where atmospheric CO2 may have decreased).
The figure also shows a period when both temperatures and CO2 concentration levels increased (from 1977 to 2000) but where the Pacific Decadal Oscillation was clearly a major contributor to the temperature increase.
It is only in the period from 1922 to 1947 that changes in concentrations and temperatures appear to be correlated. But usage of fossil fuels would then have been relatively small.
My assessment is that this analysis makes it very difficult to justify the conclusion by the IPCC and others that a causal correlation exists between changes in temperatures and CO2 concentration levels.
Paris Meeting of COP21 in December 2015 (Figure 2)
At the end of 2015, 189 countries submitted pledges to the twenty-first meeting on climate change (COP21) in Paris. These pledges are voluntary and there is no supervision of progress reports to the UN. It is of some interest that the submission by Bolivia declared that capitalism is “a system of death” while North Korea will have no difficulty in further reducing its emissions as already virtually no electric lights are on at night.
The following analysis by Tom Quirk is based on the top 12 countries for broadly defined greenhouse gas emissions which cover 72% of the world total (for 2012 the total was 10.85 Gt C in CO2-equivalent while total CO2 emissions were an estimated 9.68 Gt C in CO2. Source: Carbon Dioxide Information Analysis Center CDIAC)
The pledges have been standardized to be from 2012 to 2030 as countries have chosen various starting points to indicate their plans. For greenhouse gas emissions the pledges would see a 23% increase (from 7.83 Gt C to 9.59 Gt C) for the 72% fraction which have been analysed.
Figure 2: Pledges from the top 12 countries for greenhouse gas emissions.
This covers 72% of global emissions The pledges are standardized to be
from 2012 to 2030
It is clear that China is both the major contributor to the increase and the source of the greatest uncertainty. The 75% increase indicated in Figure 2 is a “best estimate”. The pledge from China is a peak in carbon dioxide emissions by 2030, with best efforts to peak earlier. The aim is to source 20% of its energy from low-carbon sources by 2030 and to cut emissions per unit of GDP by 60-65% of 2005 levels by 2030, potentially putting it on course to peak by 2027.
There was no discussion on limiting CO2 emissions from forest and peat fires. No estimates of these emissions are included in the total which are now about 50% of global CO2 emissions and occur in the Amazon basin, sub-Saharan Africa and Indonesia. In short, even if pledges are met total emissions could be even higher than pledged – or quite a bit lower.
However what is clear from the pledges is that China and India will become the largest emitters of greenhouse gases with rises in the standard of living in both countries. Why should they curtail their growth?
Accuracy of Temperatures (Figures 3 & 4)
There are also questions about the accuracy of the temperatures published by official agencies and used by the IPCC.
First, published daily temperatures are calculated only by averaging the minimum and maximum. However, what if Australia’s average temperatures were calculated from temperatures recorded every 30 minutes?
|Figure 3: Temperatures measured at 30 minute intervals through a 24 hour day. |
The solid black line is the weighted average of readings every 30 minutes.
The dashed red line is the average of the minimum and maximum temperatures
Research by Tom Quirk shows that, in the central desert region (such as Alice Springs), the average over 30 minutes is about the same as with the averaging of minimum and maximum (Figure 3). But in coastal and inland areas (such as in Cairns) averaging of minimum and maximum produces temperatures about 0.6ºC higher than if the averaging is done on a 30 minute basis. This research suggests an overall upward bias in the published daily Australian temperatures of 0.3-0.4ºC.
Second, it appears that the Bureau of Meteorology calculation of Australian temperatures has not taken account of the heat island effect which keeps temperatures up when recorded in large built up urban areas.
|Figure 4: BOM records of direct maximum and minimum temperatures at the BOM office |
in central Melbourne and at Laverton airport. The central Melbourne minimum would be
much lower if account was taken of the urban heat effect
Figure 4 comparing maximum and minimum temperatures at the BOM office in central Melbourne with those at Laverton shows similar maximum temperatures but much higher minimum for central Melbourne because more heat is retained in urban Melbourne.
Thirdly, although a recent review of temperature records of Australia’s Bureau of Meteorology stated that it could not conclude whether there has been an upward or downward bias, it indicated that there was uncertainty about the adjustments made to “raw” temperatures by the BOM. Submissions by independent experts justifiably claimed the adjusted temperatures had an upward bias.
What conclusion can be made about the accuracy of the temperature increase of about 0.8ºC of a degree since about 1900? One possibility is that about half is incorrectly calculated and the other half may well reflect natural causes. But even if the published data was accepted, it is relevant that temperatures were higher in the Medieval Warming Period (about 800 -1,100 AD and also in the Greco-Roman warm period (600 BC - 200 AD). Yet there were few fossil fuel emissions then. In fact, temperatures in those periods were likely higher than the scare temperature promulgated by warmists that they should not increase by more than 2ºC since industrialization.
Droughts and Rainfall (Figure 5)
Much attention is given in the media and elsewhere to areas experiencing below average rainfalls and droughts and claims are made that these illustrate the effects of global warming. However, an examination of the variations in Murray Darling Basin’s annual rainfall clearly shows no connection with levels or variations in Australia’s average temperature. Indeed, there is no statistically significant change in MDB rainfall since 1900 (Figure 5).
Past Australian droughts occurred when global temperatures were lower than now and wetter years occurred when such temperatures were rising. There is no reason to expect that to change.
Antarctic and Arctic Ice Sheets –Sea Levels and the Reef (Figures 6 & 7)
Sea levels have been increasing over recent years and, if higher temperatures caused large ice sheets and glaciers to melt, sea levels would rise further and low-lying land would become more susceptible to flooding. In fact, some owners of properties close to the ocean are already being stopped from development by measures that have been introduced by councils because of such alarmism (Figure 6).
However, IPCC reports have predicted much higher sea levels than actually occurred. Satellite measurements of sea levels from 1994 show an average rate of increase which, if continued, would result in levels about 30 centimetres higher by 2100. Most residences would readily be able to protect themselves against such an increase.
As to ice levels (Figure 7), until recently the extent in the Arctic had been falling even
though global temperatures were not increasing.
However, melting ice in the Arctic has no effect on sea levels because the ice there is already floating in the sea. Canada’s North West passage has in fact been navigated in earlier periods when fossil fuel usage was low.
In the Antarctic, the total ice area there has been increasing and recently reached record levels. Break offs of sections of the Antarctic ice sheet attract media attention but such break-offs are normal. Satellite data covering the past thirty years show a distinct cooling of the Antarctic region.
Changes in Northern and Southern Icecaps
Changes in Northern and Southern Icecaps
As to the Great Barrier Reef, alarmism by conservation bodies has been shown to be unwarranted by the declaration last year of an international heritage agency that the reef is not in danger of destructive bleaching. Most of the reef recovered from the bleachings of 1998 and 2002, which probably resulted from the temporary warming of sea water during the light winds which occur at the time of El Ninos and that limit the flow of cooler water across the reef. There are present concerns about the reef but the Reef Authority says it is too early to assess the extent of damage from bleaching.
David Attenborough claimed in his ABC program last week that the reef is ten thousand years old, which suggests that it has already experienced temperatures higher than the present ones.
Any action by Australia to reduce emissions would not help to protect the reef unless there is an effective international agreement by major emitters.
Temperature Measurements and Predictions (Figure 8)
A key temperature test is to examine the predictions used by the IPCC which have been calculated
by modelling. Figure 8 shows that none of the supposed expert modelling used by the IPCC as a
basis for its predictions coincides with actual temperatures published and shown in the figure as
observations. The published measured temperatures are much lower than the model predictions.
The marked difference shown between global temperature predictions and measurements published is
still said by some to support the dangerous warming thesis. The difference for the years 2001 to the
present is said to be missing heat that has gone into the ocean. But little or no increase in ocean
temperatures has occurred and the missing heat has not been found. Most scientists do accept that, if
atmospheric CO2 were to be doubled from the existing 400 ppm to 800 ppm, this would be likely to
raise the global temperature by 1C.
But models predicting rises of 2C to 4C to the end of the century do not take account of evaporation
from the oceans, which reduce upwards radiation.
Bill Kininmonth has published estimates of the temperature increase taking into account evaporation.
These predict global temperature increases of less than 1C and there is some satellite evidence to
support this approach.
Further, although the effects of the phase changes in the Atlantic and Pacific oscillations are seen in the temperature and CO2 time series, the influence of the oceans on the atmosphere is not well accounted for in the computer modelling. In fact, since the timing of these ocean changes is not well understood, their future effects cannot be projected by computer modelling.
I summarise my assessment as follows. There are fundamental faults in the statistical and scientific analyses used to justify the need for early comprehensive mitigatory action by governments; claims of a consensus on the IPCC science have no credibility and account is not taken of the long history of faulty analyses by scientists more generally; examination of the temperature and CO2 concentrations data indicate that any green house effect on temperatures to 2100 is likely to be very much less than the IPCC (and other believers) predict; there is no satisfactory explanation of why temperatures did not increase during two lengthy periods when fossil fuel emissions did so; new research adds to existing evidence that temperature increases in the last 100 years or so have been considerably overstated; new research also suggests that the extent of carbon dioxide in atmospheric concentration is much smaller than previously thought; there is no substantive evidence of threats from rising sea levels or melting of sea ice in the Arctic or Antarctic; there is no evidence of any significant change in average rainfall or that droughts and other severe weather events are likely to occur more frequently. As pointed out by analysts such as Ridley, the increase in carbon dioxide over the last century has been beneficial in allowing and encouraging additional growth of vegetation.
In a word, my assessment is that the best policy for governments, businesses and individuals is to adapt to changes in climate and welcome the additions to CO2.
Des Moore, a former Deputy Secretary of Treasury, is Director of the Tom Quirk trained as a nuclear physicist at the University of Melbourne where he took courses in meteorology. He has been a Fellow of three Oxford Colleges