Archives for July 2007

I have previously posted comments about this paper, published in the Journal of Quaternary Science that provides evidence for the generally cooler period known as the Little Ice Age being a global phenomenon rather than being limited to the Northern Hemisphere:

Five centuries of climate change in Australia: the view from underground

Henry N. Pollack 1 *, Shaopeng Huang 1, Jason E. Smerdon 2
1Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan, USA
2Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA

Published Online: 27 Sep 2006

Keywords
palaeoclimate • borehole temperatures • Australia

Summary and conclusions

We have analysed 57 borehole temperature profiles from across Australia to reconstruct a ground surface temperature history for the past five centuries. The five-hundred-year reconstruction is characterised by a temperature increase of approximately 0.5 K, with most of the warming occurring in the 19th and 20th centuries. The 17th century was the coolest interval of the five-century reconstruction, perhaps representing a muted expression of the Little Ice Age widely observed in the Northern Hemisphere. Because most of the boreholes were logged prior to 1976, the observed subsurface temperatures do not show the strong warming experienced by Australia in the last two decades of the 20th century. Comparison of the geothermal reconstruction to the high-quality Australian annual SAT (Surface Air Temperature) time series in their period of overlap shows excellent agreement. The full geothermal reconstruction also shows excellent agreement with the low-frequency component of dendroclimatic reconstructions from Tasmania and NewZealand. The warming of Australia over the past five centuries has been about two-thirds that experienced by southern Africa, and only about half that experienced by the continents of the Northern Hemisphere in the same time interval.

This paper provides evidence for different regional responses to global climate change and illustrates the fact that the world has warmed since the end of the LIA, with half of the warming occurring in the 20th century.

I came accross this paper in the latest edition of the Journal of Quaternary Science entitled: ‘A pre-deforestation pollen-climate calibration model for New Zealand and quantitative temperature reconstructions for the
past 18 000 years BP.’ JQS (2007) 22(5) 535–547

JANET M. WILMSHURST,1* MATT S. McGLONE,1 JOHN R. LEATHWICK2 and REWI M. NEWNHAM3
1 Landcare Research, Lincoln, Canterbury, New Zealand
2 National Institute of Water and Atmospheric Research, Hamilton, New Zealand
3 University of Plymouth, School of Geography, Plymouth, Devon, UK

In case any readers don’t know, the current 12,000 year old interglacial period that we are fortunate to live in is known as the ‘Holocene,’ SST refers to ‘Sea Surface Temperature, ‘ MAT is ‘Mean Annual Temperature,’ and BP is ‘Before Present.’

The Abstract says:

Quantification of modern pollen rain–vegetation–climate relationships in New Zealand has been complicated by human destruction of at least 75% of the original forest cover since ca. 750 years BP, causing contemporary pollen rain over large areas to bear little resemblance to the pre-human vegetation. We use a pre-deforestation pollen database to circumvent this complication. The relationships between the pre-deforestation pollen assemblages and six climatic variables were explored using principal components analysis and constrained regressions (redundancy analyses). Quantitative estimates of the most significant climate variable (mean annual temperature) were made at seven lowland to montane fossil pollen sites from throughout New Zealand using the modern analogue technique and a transfer function. These showed an initial increase in mean annual temperature after 18 000 cal. yr BP, a cooling at the time of the Antarctic Cold Reversal (centred on 13 500 cal. yr BP) and continuation of warming from ca. 12 000 cal. yr BP across the Younger Dryas chronozone, reaching a Holocene thermal optimum that may have been between 1.5 and 3.08C warmer than present and lasted from 9000 to 7000 cal. yr BP depending on the site. Cooling to present-day temperatures was well advanced by 4000–3000 cal. yr BP.

The paper concludes:

It is clear that the early Holocene was an unusually warm period with the pollen results, marine core assemblage, and isotopic SST estimates and other proxy biological evidence pointing to several millennia of MATs between 1.5 and 3.08C above those of the early 20th century. Given that there is considerable alarm about similar increases in MAT by the end of the current century, these results suggest that the early Holocene could profitably be used as an analogue to explore the consequences for biological change.

Apologies to those of an alarmist disposition, but I have an opinion piece published here on TGGWS, copied below. It is based on what I have written and posted here and elsewhere:

Al Gore’s An Inconvenient Truth (AIT) and Martin Durkin’s The Great Global Warming Swindle (TGGWS) are two documentaries presenting two very different perspectives on the current level of the scientific understanding of the Earth’s complex climate system.

AIT presents the science as being settled and computer models as being reliable. Everything bad in the world is caused by man-made CO2, from more intense hurricanes, tornados, rising sea levels, melting glaciers, floods, droughts, heat waves, and disease, to drowning polar bears.

The main thrust of TGGWS is that the science isn’t settled and there is an alternative explanation. The “enhanced greenhouse effect” isn’t behaving as climate models suggest that it should, and climate change is being used as a vehicle for an anti-human, anti-capitalist, anti-mobility agenda by groups masquerading as “green.” Others are making a living by perpetuating the global warming industry, while bandwagon politicians seek to raise “green” taxes, control enterprise, mobility, and lifestyles via energy policy.

Scientists who subscribe to the claimed “consensus” view have described AIT as having the science “about right”. TGGWS, on the other hand, has been subjected to intense scrutiny and attacks from the day it was first shown on the UK’s Channel 4 TV.

Let’s examine some of the contentious points starting with Al Gore’s 600,000-year graph of temperature and CO2 derived from ice cores. Gore fails to mention that the graph shows CO2 lagging temperature by hundreds of years, rather than CO2 driving temperature, a point that was made in TGGWS. The ice core data tells us little or nothing about the sensitivity of climate to man-made CO2.

Israeli Physicist Nir Shaviv, who appeared in TGGWS, has published his empirical calculation of climate sensitivity of a maximum of 1C to 1.5C for the iconic doubling of CO2 to 560 parts per million. Contrast this with the Intergovernmental Panel on Climate Change (IPCC) computer modelled scenarios of 1.1C to 6.4C.

The infamous “hockey stick” graph of temperatures for the past 1,000 years is another point of disagreement between Gore and Durkin. It consists of a horizontal “handle” of reconstructed “proxy” data showing a stable temperature, onto which modern day instrumental measurements have been grafted to show a rapid 20th century rise in global temperatures.

The use of these two different types of data alone is ample cause for concern, yet this graph was the “poster child” of the IPPC 2001 report and replaced the one the IPCC used in their 1995 report, which clearly showed a Medieval Warm Period (MWP), followed by a cooler period known as the Little Ice Age, a version of which was used to illustrate the point in TGGWS.

Research published by Steve McIntyre and Ross McKitrick (2003, 2005) showed that the hockey stick shape was the result of seriously flawed methodology. The 2006 US National Academy of Sciences (NAS) panel upheld the major criticisms made by McIntyre and McKitrick including the advice that strip-bark bristlecone pines should not be used in climate reconstructions.

However, the controversy over the global extent of the MWP continues, given that there are regional differences in the way the world warms or cools. The temperature rise in Australia over the past 500 years is only about half of that experienced by the continents in the Northern Hemisphere during the same period.

Both the CO2 and solar theories seem to have suffered from a correlation breakdown or “divergence”. There was a period of global cooling from the 1940’s to the 1970’s despite increasing levels of atmospheric CO2. Solar activity also fell during this period suggesting a solar link.

Claims by CO2 driven warming proponents that the cooling was caused by sulphate aerosol pollution reflecting sunlight don’t really stand up to scrutiny, given the fact that emissions from developing countries have increased markedly since the late 1980’s.

The Svensmark/Friis-Christensen graph used in TGGWS showing a correlation between the length of the 11-year solar cycle (as a measure of solar activity) and temperature has been criticised because it stops in 1980. Butler and Johnston, using data from Armagh Observatory, Northern Ireland, published similar findings in 1996.

After 1985 solar activity started to decrease yet global temperatures continued to rise. Nir Shaviv is a proponent of a possible solar explanation for this that requires the suggested link between cosmic ray flux and clouds to be real. Svenmark’s successful pilot experiment, published in 2006 provides experimental support for such a link. A much larger experiment at CERN in Switzerland should be completed by 2010.

It is important to note that the IPCC rate the “level of scientific understanding” of solar irradiance as “low”, and solar eruptivity and cosmic ray flux as “very low”.

Professor Carl Wunsch was far from complimentary about climate models when he appeared in the original version of TGGWS. He did not appear in the ABC version because he claimed his contributions had been shown out of context and misrepresented his views.

The release of the original emails to Professor Wunsch from TGGWS makers Wag TV revealed that he was well aware of the documentary’s perspective:

… I wanted to email you to outline the approach we will be taking with our film to clarify our position. We are making a feature length documentary about global warming for Channel Four in the UK. The aim of the film is to examine critically the notion that recent global warming is primarily caused by industrial emissions of CO2. It explores the scientific evidence, which jars with this hypothesis and explores alternative theories such as solar induced climate change. Given the seemingly inconclusive nature of the evidence, it examines the background to the apparent consensus on this issue, and highlights the dangers involved, especially to developing nations, of policies aimed at limiting industrial growth …

Assuming Prof Carl Wunsch didn’t dupe himself into writing it, we have his compelling view of the Gulf Stream scare from Nature, April 8, 2004:

Sir -Your News story “Gulf Stream probed for early warnings of system failure” (“Nature” 427, 769 (2004)) discusses what the climate in the south of England would be like “without the Gulf Stream”. Sadly, this phrase has been seen far too often, usually in newspapers concerned with the unlikely possibility of a new ice age in Britain triggered by the loss of the Gulf Stream. European readers should be reassured that the Gulf Stream’s existence is a consequence of the large-scale wind system over the North Atlantic Ocean, and of the nature of fluid motion on a rotating planet.

The only way to produce an ocean circulation without a Gulf Stream is either to turn off the wind system, or to stop the Earth’s rotation, or both. Real questions exist about conceivable changes in the ocean circulation and its climate consequences. However, such discussions are not helped by hyperbole and alarmism. The occurrence of a climate state without the Gulf Stream anytime soon – within tens of millions of years – has a probability of little more than zero.

TGGWS malaria expert Paul Reiter resigned from the IPCC over alarmist claims about malaria and global warming. He has also poured scorn on Gore’s malaria claims:

I am a specialist in diseases transmitted by mosquitoes. So let’s talk malaria. I wondered how many had taken anti-malaria tablets because they had seen Al Gore’s film, “An Inconvenient Truth”, which claims that Nairobi was established in a healthy place “above the mosquito line” but is now infested with mosquitoes – naturally, because of global warming. Gore’s claim is deceitful on four counts. Nairobi was dangerously infested when it was founded; it was founded for a railway, not for health reasons; it is now fairly clear of malaria; and it has not become warmer. Pseudoscience will damage your health and your wealth just as surely as malaria.

Gore claimed that 35,000 people died as a result of the 2003 European summer heat wave, due to man-made global warming. Equally pertinent but not mentioned by Gore is that there are about 100,000 excess winter deaths in Europe each year, and 25,000 to 45,000 in the UK. Contrast this with the estimated 2,000 UK deaths during the 2003 heat wave. Recent peer reviewed science by Chase et al (2006), and Fischer et al (2007) casts doubt on the claim that European heat waves are due to man-made CO2.

Gore’s inclusion of hurricane Katrina suggests that increased hurricane intensity is linked to global warming, but this is not backed by the World Meteorological Organisation “consensus statement”, or a raft of recent papers. Hurricane expert Chris Landsea resigned from the IPCC in 2005 saying, “I personally cannot in good faith continue to contribute to a process that I view as both being motivated by pre-conceived agendas and being scientifically unsound”.

John Chrsity of The University of Alabama research group provides support for the claim made in the TGGWS that the planet’s surface warming is greater than the warming in the lower atmosphere (troposphere), which contradicts climate model predictions for enhanced greenhouse warming. Previous unfounded criticisms of the Christy et al data have centred round an error correction of 0.035C, which ignored the fact that this was within the quoted margin of error in the original paper of 0.05C. Their latest data published in 2007 confirms the discrepancy between climate models and observations.

Land use change expert Roger Pielke Sr, of the University of Colorado, resigned from the IPCC in 1995 due to the narrow focus on CO2, but he didn’t appear in TGGWS. In 2005, he also resigned form the US Climate Change Science Programme (CCSP) Committee “Temperature Trends in the Lower Atmosphere-Steps for Understanding and Reconciling Differences” stating:

I have given up seeking to promote a balanced presentation of the issue of assessing recent spatial and temporal surface and tropospheric temperature trends. This entire exercise has been very disappointing, and, unfortunately is a direct result of having the same people write the assessment report as have completed the studies.

The broad conclusion is that the multi-decadal global climate models are unable to accurately simulate the linear trends of surface and tropospheric temperatures for the 1979-1999 time period, on the regional and tropical zonally-averaged spatial scale. Their ability to skilfully simulate the global averages surface and tropospheric temperature trend on this time scale is, at best, inconclusive. This has major implications for the impacts community.

Studies such as the US National Assessment and Chapters and the IPCC which use regional results from the multi-decadal climate models are constructed on models which have been falsified in their ability to accurately simulate even the linear trend of the tropical zonally averaged surface and tropospheric temperature trends over the last several decades. Since almost all impact studies require regional and smaller scale resolution, the current generation of multi-decadal global climate prediction models is inappropriate to use for impact prediction for the coming decades.

In conclusion, Gore’s AIT goes way beyond any consensus and doesn’t do justice to the many scientific uncertainties. Durkin’s TGGWS has evolved since the first showing in response to some criticisms, and could have made some of the contentious points clearer. However, the debate that some so badly want closed down is alive and well, albeit increasingly vitriolic. There is, however, a much bigger fish to fry than either AIT or TGGWS – namely the IPCC itself. I look forward to the same intense scrutiny being applied to the IPCC’s climate science monopoly.

Snow on the Dandenongs and the heaviest falls on Mt Buller for seven years provide further proof of “Climate Change”, if not of global warming. Keeping that distinction in mind is a precondition for not being swindled.

A second line of defence against mumbo-jumbo is to recall that the philosopher Karl Popper promoted falsifiability as essential to the logic of scientific enquiry. He reasoned that any hypothesis which is so structured as to be incapable of refutation is pseudo-science.

The “Climate-Change” band trumpets all data about rising temperatures as evidence to buttress their hypothesis. However, not so long ago they were perplexed by inconvenient truths such as the occasional severe winter. On the face of it, such cold snaps surely count against global warming? This is where the “Extreme Event” comes in handy.

The “Climate-Change” faithful now have the power to levitate above the embarrassment of awkward evidence. To deal with exceptions, they have conceived the metaphysical category of the “Extreme Event”. This phrase does not refer to weather which has extreme consequences, such as the past 48 hours in Victoria. The significance is altogether different. The “Extreme Event” is a device for ruling out the very possibility of contrary evidence and, thus, for denying the prospect of Popperian falsification.

The “Climate Change” sophists proceed thus: the anthropogenically-enhanced greenhouse effect does more than push up average temperatures. It also increases instability. So, while a denser greenhouse mostly makes the planet hotter/drier, it will also make it colder/wetter in some places at certain times.

That Janus outcome is indeed possible. Hence, to decide whether each event is evidence for or against one or other of the current explanations for the latest changes in climate, we need to specify causes. The devastation from Hurricane Katrina was so extreme because of policies of US governments. It is pseudo-science to attribute every hurricane or blizzard to an amorphous “Climate Change”.

If all swings in the weather are worshipped as manifestations of “Climate Change”, that hypothesis is elevated above the realm of rational enquiry. Its advocates have entered the domain of theology where all outcomes — even the cruelest — are accepted as God’s working in his mysterious ways to reveal his omnipotent Goodness.

by Humphrey McQueen in an article entitled:
How the “Climate-Change” faithful spin cold weather
at Crikey.com.au
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