The Science is Uncertain

Despite Al Gore's assertion (in An Inconvenient Truth) that none out of a sample of 928 technical papers disagreed with the basic science of global warming, it seems an inconvenient truth that only a very small percentage of climate scientists fully support the interpretation of the link between climate change and CO₂ emissions that Gore assumed to be beyond discussion [1] - presumably because accepting that humanity is affecting the climate and that CO₂ emissions are part of the story is not the same as accepting that CO₂ emissions are all that matters, and that the mechanisms involved are adequately understood. The residual uncertainties can be illustrated as follows:

• some scientists clearly acknowledge the uncertainties of climate models [1, 2];

• many declare the science of global warming settled, because they don't understand how science works. There is a lot of scope for better theories to emerge [1];

• climate change is understood to be occurring faster than predicted by models developed by the IPCC [1] - which highlights the limitations of the models.

  • [The IPCC's 2007 analysis suggested that models were now becoming more accurate in 'predicting' the past - though if this is achieved by inserting 'fudge factors' to achieve this outcome (as some critics have alleged) rather than building models off physical laws, then this does not guarantee future reliability of those models];

• a large number of factors are now contributing to climate change [1]. Thus even if CO₂ emissions were a trigger for change it may no longer be the only issue that needs consideration;

• CO₂ emissions have been suggested to account for only 26.5% of climate change (as compared with the IPCC's estimate of 48%) because numerous other factors have allegedly been downplayed, such as (a) ozone (b) methane emissions (c) albedo effect of soot on ice and snow (d) various aerosol effects and (e) solar effects [1].

  • [IPCC's February 2007 analysis suggested that while carbon emissions only accounted for half the positive forcings (ie those contributing to global warming), there are negative forcings of about the same magnitude. None-the-less methane, nitrous oxide and ozone were individually non-trivial positive forcings, and collectively have an influence roughly the same as as carbon emissions]

• some experts have apparently seen a need to substantially upgrade satellite observation systems to make reliable basic data about climate change available ("Satellite Observation of the Climate System: The Committee on Earth Observation Satellites (CEOS) Response to the Global Climate Observing System (GCOS) Implementation Plan (IP)");

• evidence appears to exist of significant reduction in solar energy reaching the earth - the global dimming phenomenon - because energy is reflected by aerosol pollution (which create some of the negative forcings IPCC identifies as roughly equal to the positive forcings associated with carbon emissions). Reducing the use of fuels that generate carbon emissions will also presumably reduce global dimming - ie reducing fossil fuel use seems likely to have both a positive and negative effect on forcings;

• students of long term climatic history (to which the IPCC seems to have paid limited attention in its analyses) have suggested alternative theories, for example  [1]; that

  • global temperature changes correlate with sunspot activity more strongly than with CO2 increases, and that sunspot activity (though not directly linked with significant changes in solar energy output) does substantially reduce cosmic radiation, which in turn is associated with reduced cloud cover and significantly increased warming;

  • while greenhouse gases have an important impact on the earth's climate, water vapour (which comprises 98% of all greenhouse gases) is the only one with any significant effect. An El Nino event in 1997 significantly increased atmospheric water vapour, and preceded the record temperatures of the next few years;

  • over the past 500 million years CO2 levels have been up to 16 times greater than at present, and the peak occurred at the coldest stage of a major ice age. Over the past 400,000 years CO2 levels have correlated with temperature changes, but CO2 rises came about 800 years after temperature increases - apparently due to changes in biological activity;

• A New Theory of Climate Change suggests that the effects of greenhouse gases are less than has been assumed - and solar variations (which affect cosmic rays and thus cloud formation) may provide an hypothesis that better matches observations [1] - a view that has critics;

• Great Global Warming Swindle outlines the views of scientists who believe that global temperature changes are driven by solar activity, not greenhouse gases. [1]

• the earth's climatic history (involving several ice ages in the last million years with significant cooling and subsequent warming) suggests that there are mechanisms for global warming (and cooling) that are unrelated to human carbon emissions;

• climatologists are said to realize that water vapour dominates global greenhouse effects - and that the effect of gases released by human activity is virtually insignificant - though water vapour is conventionally ignored by those seeking to identify human contributions to greenhouse effects (see Water vapour rules the Greenhouse system). Others suggest that water vapour is correctly ignored because it only persists for a short time in the atmosphere - and its concentration is determined by other factors (see Water Vapour: Feedback or Forcing);

  • [An aside: surely, if water vapour is the 'elephant' in the greenhouse room and its behaviour is determined by other factors, then there has to be a huge amount of effort to make sure that those other factors are well understood, and that none are neglected. The IPCC does not seen to have done this].

• polar ice caps have reportedly been observed to be melting on Mars - suggesting that whatever is happening is not solely of terrestrial origin [1];

• global warming is not the only potential cause of climate change. It is understood that current drought conditions in Australia reflect a southward shift in weather patterns (eg rain that would have fallen over Australia in the past is now falling over the ocean to the south). This seems compatible with Solomon's observations that the rapid cooling of the atmosphere above the Antarctic (as a result of ozone depletion) has apparently caused atmospheric circulation patterns around the South Pole to narrow around the Pole - and this has shifted other circulation patterns in the southern hemisphere south [1];

• some observers claim that there is a 'law of diminishing returns' in relation to the greenhouse effect of rising CO₂ levels - with 60% of the maximum warming effect being achieved by concentrations of 50ppm - and a quite negligible increase in greenhouse effect from even a doubling of current CO₂ levels and probable greater warming effects coming from other sources (eg water vapour) [1];

• it seems odd to assume that Pacific Islands are now likely to be flooded by rising sea levels [1] - as those islands have been exposed to huge rises in sea levels over the past 15000 years as continental glaciation retreated and the coral polyps that build many of them have apparently managed to keep their heads at water level. The assumption that islands will be submerged because coral can no longer grow due to higher temperatures is also an assumption that reefs will not adapt to changed conditions as they have undoubtedly done in the past;

• the science of climate modelling is subject to vast uncertainties - as indicated by the general inability of weather forecasters to look far into the future. Though the systems involved are not identical, and forecasting has been improving, this constraint should not be ignored; and

• the is a need to recognise that the earth's climatic systems will contain self-stabilizing (ie homeostatic) mechanisms;

Bias is Possible

The IPCC's conclusions are being treated as 'gospel' though:

• the IPCC was established to focus only on the effect of human-induced climatic change [1]. Moreover:

  • its 2007 February analysis presents a refinement of that Panel's 'consensus' theory about climate change, whilst not mentioning alternative theories - and thus, even if its theory is correct, the IPCC erodes its own credibility by leaving many questions unanswered. Unfortunately such one-eyed behaviour is characteristic of politicised, rather than professional, organisations. Where a particular answer is politically favoured, Daniel Ellsberg's analysis of the Pentagon showed that selective staffing and evaluation of evidence can result in that conclusion emerging [1];

  •  20 years ago climate research became politicised in favour of one hypothesis - based on study of greenhouse gases. Those following different theories encountered impediments to their careers. It was only in 2005 that funding could be obtained to conduct research on an alternative plausible hypothesis [1];

  • the global warming scare has been described as scientific fraud [1]

  • it may have been a big mistake for governments to have exclusive reliance, in matters of great complexity, on a single source of analysis of the implications of climate change (ie the IPCC) [1].

• while the 'consensus' method used to develop the IPCC's conclusion on the science of climate change is potentially powerful, it does not guarantee truth (ie a 'flat earth' was once the established consensus view);

• professional critique has been levelled at the IPCC's work [1]. For example:

  • one observer suggest it to be defective in relation to: under-estimating solar and natural greenhouse effects; ignoring earlier periods of higher temperatures in order to portray recent temperature rises as exceptional; overstating temperature rises; being inconsistent with a law of physics; and tripling the man-made greenhouse effect [1];

  • another suggested that: it ignored past warm periods and the  saturation effect which limits the heating effect of increasing CO2 concentrations; sunspot activity suggests that the 1976-2000 warming trend is ending; CO2 emissions only correlate with warming from 1976 to 2000 ; claims that the science is settled and the debate is over are false; there is no evidence that CO2 emissions cause the weather effects blamed on them; and 'tropical' diseases are mainly a product of poverty and poor sanitation; [1]  .

• likewise the Stern review of climate change (which explored the economic consequences of assuming that the IPCC's conclusions were valid) has been described as:

  • overly simplistic and perhaps counter-productive [1];

  • based on unrealistic assumptions that maximize the estimated damage from climate change and the need for immediate (rather than deferred) responses [1];

  • a biased exercise in speculative alarmism [1]

• the IPCC's methods have long appeared technically inadequate to the present writer because the impact of global warming on sea levels was presumed to be linear and related mainly to differential expansion of water relative to the earth (eg a <1m rise in sea levels was forecast to result from a 2-3 degree Celsius rise in global mean temperatures - whereas climatic history is understood to suggest that sea level changes can be much larger (ie tens of metres) and occur quite quickly - presumably because feedback affects emerge as changes occur in ocean currents or atmospheric circulation patterns which alter the way heat is distributed globally and thus the amount of water locked up as ice. The Biblical account of the 'great flood' (which is shared by many peoples worldwide and presumably refers to the 100m or so rise in sea levels that followed the ending of the last ice age) suggested that  water covered the 'whole earth' as a result of something that happened over a short period (eg sudden collapse of the then North American ice sheet - a type of collapse which is now suspected to be possible [1])

  • [IPCC's February 2007 analysis suggested that:

    • sea levels had been 4-6m higher than at present during the last inter-glacial period 125,000 years ago;

    • there were possible feedback effects (eg related to release of CO2 from oceans) that could increase warming which (a) made it difficult to estimate the amount of CO2 emission reduction needed to achieve stability and (b) created uncertainty about the extent of sea level rises;

    • dynamic processes associated with ice flow (which could also increase potential sea level rises) might have an effect, but this was not taken into account in forecasts because it was too hard to estimate;

    • modest sea level rises over the next century (<1m) were likely associated with thermal expansion and some ice melting - a conclusion that ignored the (uncertain) effect of feedbacks;

    • a 7m rise in sea levels might occur before 2200 if the Greenland ice sheet were to disappear;

  • however its analysis made no obvious mention of the very large (100m) fall and (apparently sudden) subsequent rise in sea levels during the last ice age;

  • but a forthcoming IPCC report may warn that it may no longer be possible to prevent severe sea level rises (eg 4-6m) [1]

'Business as Usual' Solutions may not Exist

Even if it is assumed that CO₂ emissions are the only significant cause of climate change, it is not necessarily a trivial matter to reduce emissions. For example:

• practical alternatives must involve 'high grade' energy sources - ie those which make a lot of energy available for use with little effort. There is no shortage of energy in nature - but there are shortages of energy that is readily / cheaply available for use. If very low-grade energy sources were all that were available (ie those where the energy available for use is only (say) 2-3 times the energy that must be expended in obtaining it which could apply to some renewable energy sources - as compared with the 10-50 times that can be available from fossil fuels) then the energy consumption / unit of GDP would increase dramatically and it may be physically impossible to produce enough non-fossil fuels to satisfy human demands;

• It has been suggested that emissions might be stabilized by: development of nuclear energy; increased energy efficiency; CO₂ capture; and renewable energy [1, 2]. However, all those options have limitations:

  • Nuclear energy is not an environmentally problem-free option, though this might change if fusion proves viable. Nuclear power also requires access to water which will tend to favour sites near cities that are still available because they are of high conservation value. Sites would also presumably need to be at least 10-20m above sea levels, if rising sea levels are one of the fears prompting such developments; 

  • Efficiency is a good idea but hardly novel;

  • CO2 capture would greatly reduce energy efficiency;

  • Renewable (ie ultimately-solar) sources are less 'concentrated' (ie of lower grade) than fossil energy sources and are thus likely to be much less 'profitable' to develop - both economically and energetically - though some see light at the end of the end of this tunnel [1]. Also determined attempts by autocratic government to replace fossil fuel use in vehicles in Brazil appeared to generate adverse side effects, and to have only a marginal impact on overall oil consumption  [1];

• various observers have questioned the feasibility and cost of reducing CO2 emissions:

  • there is a great deal of rhetoric about climate change - but the problem is that there is no solution. The IEA did an audit of 1400 policies to reduce fossil fuel use, and found that global emissions might at best only rise 30% by 2030 instead of 55%. To have any significant effect caps on carbon emissions would have to be set so low as to shut down the economy [1];

  • decarbonisation of the world’s economy would cause huge economic dislocation [1] ;

  • the public is being misled about the cost of reducing carbon emissions, as these costs will be very high and may not come smoothly; [1];

• on the other hand:

  • potentially plausible options were suggested based on: phasing down use of coal, oil and nuclear power; increasing use of natural gas to 2030; large increases in energy efficiency; and development of new renewable energy technologies involving solar power, wind and geo-thermal energy [1].  [[However this assumed rapidly increased global economic productivity of energy use based on past US experience, though some of the latter was due to the shift off-shore of energy intensive production]];

  • achieving large reductions in carbon emissions was suggested to be easy - largely on the basis of the prospective development of clean coal technologies [1];

  • huge business opportunities have been perceived in tackling global warming [1] [[a conclusion that will presumably be correct if (a) development of alternative high grade energy technologies is possible and (b) CO2 emissions are the only significant factor in climate change]];

• it has also been suggested that the cost of reducing fossil fuel usage will be inconsequential because future incomes will be greater than today's. [1] However this assumption requires that there be no economic shocks, and attempts to cut the use of fossil fuels (if it proves impossible to develop other high grade energy sources) could give rise to economic shocks which could dislocate growth. It is vital to look closely at the physical relationship between the use of energy / machines and the creation of wealth. This requires assessment by physicists and industrial chemists, rather than environmentalists, economists or climatologists. The economic models cited in the above article deal with the economy in abstract / money terms - and are only valid as long as there is a ready availability of energy to do the mechanical work. At the time of the industrial revolution capitalism allowed the mobilization of financial capital to invest in physical capital (ie machines) that used fossil energy to increase efficiency in mechanical tasks. Increased efficiency reduced costs, which led to an explosion of demand and ultimately to self perpetuating economic growth (which was initially largely a reflection of the value of the work done by machines using fossil energy). Economics now recognizes that knowledge rather than physical capital (ie machines using mainly fossil energy) or human labour is the key component of wealth creation in financial terms - because it provides the scope for firms or regions to change to focus on functions in which a competitive advantage derived from that knowledge allows high productivity to be achieved (in money terms). But there remains an unbreakable link with the escalating use of fossil energy to power the machines that (a) help with knowledge 'work' and (b) do the physical construction and the manufacturing that those with high knowledge-based incomes buy (now often from the developing world).

• many companies are falsely claiming to be carbon neutral for public relations purposes - but to be truly neutral there would be a need to consider the emissions in the entire production chain which would be no easy task, and likely to be very costly [1];

• the Business Council of Australia has argued that adjusting to reduced carbon emissions will be difficult [1]

• greenhouse gas abatement schemes promoted by Australian business would make no measurable difference to climate change [1]

• CO2 emissions are not the only environmental challenge that needs attention, and unconditional determination to reduce emissions may make it more difficult to deal with other hazards (see below);

• because economic development in emerging economies is often energy intensive, it would be impossible to have any significant effect unless any efforts are global;

• Any trading system in carbon credits will result in a large international transfer of wealth - to developed countries who can relatively easily increase energy efficiency [1]

Non 'Business as Usual' Solutions could be Hazardous

While technological advances may allow high grade clean energy sources to be identified, if this is not achieved then unconditionally slashing fossil energy consumption (which would be required to moderate the CO₂ component of the greenhouse effect) could result in economic crises, conflicts and perhaps billions of deaths over the next few decades. 

Thus targets set for reducing carbon emissions, that are not conditional upon the development of high-grade alternative energy technologies, would be either unrealistic or potentially dangerous.

Why? The whole history of humanity for tens of thousands of years has been one of population growth encountering environmental constraints that  were overcome by the more intensive use of energy.

Would it be possible to reverse this peacefully, or would less overall energy use from now on mean fewer people - perhaps a lot fewer?

Early humans were hunter-gatherers. A key factor in the growth and spread of their population was the domestication of fire (to exploit the solar energy captured in wood) which allowed: an expansion of human's geographic range into colder regions; better defence against predators; and improved ability to use available foods.

However, while one can't be certain about exact figures, the 'carrying-capacity' of the earth for humans living hunter-gatherer lifestyles was probably only something like 50m. When hunter-gatherers encountered environmental limits (about 13,000 years ago) these constraints were overcome by the development of agriculture which mobilized solar energy more efficiently.

When agrarian populations encountered limits to what could be achieved by the use of solar energy - a few hundred years ago at densities roughly equivalent to a global population of (say) 500m - fossil energy sources were mobilized, and this allowed (a) more efficient mechanised agriculture and (b) the development of vast cities productively involved in diverse other industries.

In recent decades, solutions to resource limitations and adverse environmental impacts of population and economic growth have been solved by more intensive energy use. The recent shift into knowledge and service industries in advanced economies, which has reduced their energy intensity, is somewhat misleading because energy consumption on their behalf has merely followed the shift of much manufacturing to the developing world.

There is a potential for highly destructive political instabilities if the global economy were disrupted by reduced energy consumption through unconditional cuts to CO2 emissions. Consider for example:

• global financial imbalances that appear to be associated with a 'clash' of civilizations and have the potential unless carefully defused to lead to a worse economic crisis (and consequent political conflicts) than in the 1930s (see Structural Incompatibility Puts Global Growth at Risk);

• the lack of any effective system of global governance, arguably due to difference perceptions of the nature of a desirable global system - as revealed by (for example) the failure of international community to reach agreement on what to do about the risk posed by terrorists with weapons of mass destruction (see The Second Failure of Globalization?).

Moreover, even if short term crises could be avoided, the current global population of 6bn (or anything like it) could probably not be sustained in the longer term in low-energy economies. Could enough food for 6-9bn people globally be produced by neo-agrarian technologies? Soils are depleted and water scarce in many places, and require energy intensive fertilizers, faming methods and water supplies for current levels of food production. Also, though in a neo-agrarian world, (say) 50% of people would work in agriculture (as compared with 5% in industrial economies), what would the 3-4bn people living in future in dispersed villages who were not engaged in agriculture do for a living without cheap energy sources? It might be that they would be most 'productively' be occupied if recruited into armies to capture others' treasure left over from energy-intensive times (and wipe one another out until the global population got back to a sustainable neo-agrarian level - say 500m).

There are many other environmental challenges that need to be met in the longer term, for which energy-intensive solutions may be required that could be rendered impossible if unconditional reductions in CO2 emissions resulted in reduced overall energy usage. Examples of other challenges that appear to require simultaneous solutions include:

• the toxic effects of many chemicals [1];

• declining food quality that seems to be associated with first world 'malnutrition' as revealed by the escalation of obesity and the chronic degenerative diseases that threaten to overwhelm health systems. This may require solutions that include 're-engineering' the food chain to bring producers and consumers closer in time and space;

• loss of biodiversity, which may be an environmental challenge with more serious potential consequences. Analysts have suggested that (say) 50% of species could be lost in 50 years (Leakey R etal The Sixth Extinction, 1996). When such events have occurred previously in earth's history they have been followed by the emergence of new species to occupy available ecological niches. At risk could be the Pleistocene environment in which human beings have become the dominant species over the past 5m years;

• human consumption of about 40% of global biomass - which leaves limited biological resources for other species;

• limitations of available fresh water and soils;

• potential pandemics.

How is Success Determined?

If emissions can be reduced effectively, it will take 10-30 years for this to have any detectable climatic effect and 100-300 years to get the full effect [1];