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| Number of hot summer days in north-west NSW | Number of frosty winter days in south-central NSW |
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(As simulated by the CSIRO regional climate model in which greenhouse gas concentrations were increased according to the IS92a emissions scenario.)
2.80 CSIRO also modelled potential changes in rainfall. They said that:
Figure 2.4 illustrates the way in which natural variations can obscure a small overall trend, which in turn masks substantial changes in the number of extremes. As described in the caption, the panel on the right indicates that from the middle of this century there is an increased chance that south-western NSW will receive an amount of spring rainfall that was regarded as `dry' in the latter part of the twentieth century. [15]
Figure 2.4
| Simulated spring rainfall over south-western New South Wales | The number of dry spring seasons experienced per 20 years. |
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(`Dry' is defined as a spring season where rainfall is below that of the 4th driest year in the period 1961-2000.)
2.81 However, in presenting their results for this modelling, CSIRO made an important qualification: `The problem for policymakers is that while these results are plausible, they are from a single experiment from a regional climate model. Different models are likely to show quantitatively different changes over the same regions'. [16]
2.82 Making exact predictions for climate change in the Australasian region is obviously subject to continuing uncertainties, caused by the difficulty in obtaining regional level resolutions from global climate models, uncertainty about ENSO patterns, and wide predicted ranges of rainfall change. However, scientists have been able to isolate probable changes including: dramatic changes in rainfall levels and intensities, with a strengthening view that large parts of Australia could become much drier; damage to the Great Barrier Reef; changes to river flows and flood frequencies; damage to biodiversity; worsening dryland salination problems; and resultant damage to important industries such as tourism and agriculture, and possible damage to built infrastructure through cyclones.
2.83 The lack of information about the potential costs of climate change impacts in Australia at both a national and regional level was of serious concern to the Committee during its inquiry. Although there are some uncertainties regarding impacts, there has been no attempt by the Government to translate these impacts into economic and social costs. The Committee acknowledges that making a better assessment will require progress on the resolution of regional climate models, and it urges the Commonwealth Government to devote adequate resources into such research, and into developing assessments of the possible environmental, social, and economic impacts of climate change within Australasia. In the Committee's view, such costs ought to be as much a part of current debates about national abatement action as the costs associated with reducing emissions.
2.84 A particularly important issue presented to the Committee was that of the level at which the global climate system could be realistically stabilised, and how great a reduction in emissions would be required to do so. The IPCC has, in the Second Assessment Report modelled a range of pathways to a stabilisation of global greenhouse gas concentrations in the atmosphere at various levels: at 450 parts per million (ppmv), 550, 650, 750 and 1000 ppmv. They state that `the steeper the increase in emissions (hence concentrations) in these scenarios, the more quickly is the climate expected to change… for a given stabilisation concentration value, higher emissions in early decades require lower emissions later on'. [17] A diagram showing possible pathways to stabilisation is included overleaf.
Figure 2.5
Co-operative Research Centre for Southern Hemisphere Meteorology, Monash University
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2.85 The IPCC lists the temperature increases that would result from a stabilisation of the climate system at various levels:
2.86 These temperature increases would be the result of increasing concentrations of CO2 alone (which accounts for 60 per cent of current concentrations, and will increase to 75 per cent by 2100), excluding other greenhouse gases with much higher forcings, and also excluding the effects of aerosols (which can cause a counteractive cooling). However, given the IPCC's statement that the greenhouse forcings of methane and nitrous oxide would also increase in absolute terms by a factor of between 2 and 3, such temperature estimates may be slightly conservative. [19]
2.87 As discussed earlier, even if the global concentration of emissions was stabilised at a level of 550 ppmv, sea levels would continue to rise for many centuries, potentially causing massive social and economic impacts and presenting enormous challenges for political stability and adaptation. The IPCC Second Assessment Report states that:
The stabilization of greenhouse gas concentrations does not imply that there will be no further climate change. After stabilization is achieved, global mean surface temperature would continue to rise for some centuries and sea level for many centuries. [20]
2.88 The IPCC's Second Assessment Report discusses the task of stabilisation separately for the three major greenhouse gases, carbon dioxide, methane and nitrous oxide. The Committee also heard evidence about the level of abatement required to stabilise CO2 concentrations.
2.89 Methane has a high greenhouse forcing (global warming potential, GWP) of about 21 times that of CO2. However, according to the IPCC, `atmospheric methane concentrations adjust to changes in anthropogenic emissions over a period of 9 to 15 years. If the annual methane emissions were immediately reduced by about 30 Tg CH4 (about 8 per cent of current anthropogenic emissions), methane concentrations would remain at today's levels. If methane emissions were to remain constant at their current levels, methane concentrations (1720 ppbv in 1994) would rise to about 1820 ppbv over the next 40 years. [21] The CSIRO was optimistic about methane, saying that: `the growth rate of methane is slowing, and if this trend continues, the concentration of methane will have stabilised by the first Kyoto commitment period'. [22]
2.90 The Second Assessment Report stated that nitrous oxide has a long lifetime of about 120 years, and that `for the concentration to be stabilised near current levels (312 ppbv in 1994), anthropogenic sources would need to be reduced immediately by more than 50 per cent. If emissions of nitrous oxide were held constant at current levels, its concentration would rise to about 400 ppbv over several hundred years, which would increase its incremental radiative forcing by a factor of four over its current level'. [23]
2.91 The rapid reduction of nitrous oxide emissions obviously has to be a global priority, and the Committee urges the Government to develop a strong focus on the reduction of national N2O emissions. Agriculture is by far the largest N2O emitting sector, with transport, stationary energy and industrial processes also making smaller contributions. The major factors influencing N2O emissions in the agricultural sector were the disturbance of land for tillage, along with biomass burning, the use of nitrogenous fertilisers and the management of animal wastes. [24]
2.92 The IPCC explains that carbon dioxide `has a relatively long residence time in the climate system - of the order of a century or more'. They explain that current emissions levels would see an increase of global atmospheric concentrations to 500 ppmv by 2100:
If net global anthropogenic emissions (ie., anthropogenic sources minus anthropogenic sinks) were maintained at current levels (about 7 Gt/yr including emissions from fossil fuel combustion, cement production and land use change), they would lead to a nearly constant rate of increase in atmospheric concentrations for at least two centuries, reaching about 500 ppmv (approaching twice the preindustrial concentration of 280 ppmv) by the end of the 21st century. Carbon cycle models show that immediate stabilization of the concentration of carbon dioxide at its present level could only be achieved through an immediate reduction in its emissions of 5070 per cent and further reductions thereafter. [25]
2.93 The Second Assessment Report suggests that to restrain atmospheric concentrations of CO2 to below 550 ppmv (a level the Committee strongly advocates, given that it would still result in a 1ºC increase in global mean temperatures, and sea level rises of between 25 and 50 cm by 2100) would require an enormous effort in greenhouse abatement during the 21st century:
If the atmospheric concentration is to remain below 550 ppmv, the future global annual average emissions cannot, during the next century, exceed the current global average and would have to be much lower before and beyond the end of the next century. Global annual average emissions could be higher for stabilization levels of 750 to 1000 ppmv. Nevertheless, even to achieve these latter stabilization levels, the global annual average emissions would need to be less than 50 per cent above current levels on a per capita basis or less than half of current levels per unit of economic activity. [26]
2.94 The IPCC also suggests that the relative importance of CO2 to the global warming problem will increase over time:
The importance of the contribution of CO2 to climate forcing, relative to that of the other greenhouse gases, increases with time in all of the IS92 emission scenarios (a to f). For example, in the IS92a scenario, the CO2 contribution increases from the present 60 per cent to about 75 per cent by the year 2100. During the same period, methane and nitrous oxide forcings increase in absolute terms by a factor that ranges between two and three. [27]
2.95 The Committee heard further evidence from scientists about what would be required to stabilise the global climate system, and the ideal level at which to aim to do so. Dr Geoff Jenkins of the UK's Hadley Centre argued that a level of 550 ppmv, whilst challenging, would avoid some of the worst potential impacts of climate change:
We have done a recent study looking at impacts of several emission strategies, both unmitigated emissions - business as usual emissions, if you like, the sort of thing that IPCC has called the IS95 scenario emissions - and also emissions which are very much less than that and would lead to stabilisation of concentrations in the atmosphere at either 550 or 750 parts per million, over a very long period of a few hundred years. There are some interesting results from that on a global basis. So, for example, in the smallest of those emission scenarios, leading to a stabilisation at 550, we find that over the course of the next hundred years - as you might expect - because emissions are lower, then a lot of the impacts are lower. The negative and, indeed, in some cases the positive impacts on changes in vegetation and on changes in water resources, run-off from rivers, for example, changes in food production, crop yield, will be reduced as you reduce the emissions. That is perhaps not a very surprising result.
What we can also see is that in the very long term, if we adopt a very low emission scenario approach, then some of the very large changes such as I have mentioned over the Amazon region - dieback of forests over the Amazon region - will be avoided even over a 300-year period. [28]
2.96 Dr Jenkins explained that driving this work was an effort to interpret Article 2 of the UNFCCC:
The reason for doing some of this work was to look at perhaps trying to interpret the word `dangerous' that comes out of the UN Framework Convention on Climate Change, that `dangerous' climate change to be avoided. Nobody really knows what dangerous means and we were trying to look at some of these impacts to see if there was any guidance on either the change in climate or the change in impacts which could help to define that word. So, if indeed the models are correct - as I said before, a lot of the results may be very model dependent - and if we look at some of the changes that we see over Amazonia and the quite rapid dieback in forests there and define that as a dangerous climate change, then that sort of thing could be avoided by going on really quite a low emissions pathway which would stabilise at 550 parts per million. [29]
2.97 The Chairman of the IPCC, Dr Watson, also emphasised the importance of Article 2 of the UNFCCC as an objective in stabilisation analyses:
If indeed we take seriously the overall objective of the climate convention Article 2 - that is to say, stabilisation of the atmospheric concentrations of greenhouse gases and hence eventually stabilisation of the climate system - one would want to say quite categorically that the Kyoto Protocol is only a small, albeit very important, first step towards the ultimate objective of the convention. The reason for that is very simple: if we were to want to stabilise the earth's climate, we would have to have global emissions lower than they are today. [30]
2.98 Dr Watson explained what kind of emissions reductions would be required to stabilise global concentrations of CO2 at 550 ppmv:
If we were to take, for example, stabilisation at 550 parts per million of atmospheric carbon dioxide - and let me just remind you that pre-industrial levels of carbon dioxide were 280 and today we currently have about 360 parts per million - and I am not saying that is the right level, I am just saying if we did, and that is the target of the European Union, global emissions of CO2 could go up from today's around seven to somewhere around eight to nine, or maybe 9½ billion tonnes per year, over the next two or three decades, and then they would have to significantly come down. They would have to, as I say, come down so that by the end of this century we would be roughly where we are today or less, and over the next 100 years they would have to decrease to, say, two to three billion tonnes. [31]
2.99 The Committee notes that this amount - 2 to 3 billion tonnes - would require a fall to emissions to between 30 and 40 per cent of 1990 levels by 2200. Dr Jenkins also offered a view on the possible path to stabilisation:
There is not a unique pathway of emissions in order to stabilise concentrations in the atmosphere. The sorts of pathways that IPCC have come up with in order to stabilise at twice the preindustrial levels, 500 parts per million, involve allowing a small change up to maybe nine or 10 gigatonnes per annum globally over the next 100 years or so but then really a quite rapid decrease and eventually, over a few hundred years, down to levels of maybe 70 per cent cutback in emissions compared to today's. This is nothing too novel. It has been known for 10 or 15 years but because of the way the carbon cycle operates you do need to make dramatic cutbacks in order to stabilise the atmospheric concentrations. [32]
2.100 The IPCC has also stated that `a range of global carbon cycle models indicates that stabilisation of atmospheric CO2 concentrations at 450 ppmv… could be achieved only if global anthropogenic CO2 emissions drop to 1990 levels by approximately 40… years from now, and drop substantially below 1990 levels subsequently'. [33]
2.101 Professor David Karoly echoed these analyses, stating that: `global greenhouse gas emissions need to be reduced to about one-third or less of 1990 levels to stabilise atmospheric concentrations… .That would need to take place in the future in an environment of increasing population and increasing energy use, particularly in developing countries. My estimate is that developed countries, to achieve a global 30 per cent level - a 70 per cent reduction - are likely to need to reduce their emissions to around 10 per cent of present emissions levels'. [34]
2.102 In the Committee's view, this is a daunting prospect for Annex 1 countries (given even the 150 to 200 years time frame), but one which will have to be faced if the worst impacts of climate change are to be avoided. Professor Karoly emphasised that reductions needed to begin soon if such a target was to be viable:
… the reductions over business as usual need to start quite soon - in fact, immediately… [in] the order of 30 per cent reductions over the next 20 years… Kyoto is an average six per cent reduction in developed countries only. The Kyoto Protocol will have no noticeable effect on observed atmospheric carbon dioxide concentrations. [35]
2.103 The Committee notes that this would require a cut in emissions to 70 per cent of 1990 levels by around 2020. It is a challenging objective, and underlines the need for Kyoto signatories to begin planning and implementing their transition to a low emissions economy immediately. On the other hand, Dr Watson argued that companies such as Shell had developed scenarios which plausibly suggested that the world could make a transition to a low carbon economy this century:
The question I think one has to ask is - and I pose it as a question, not as a policy statement: are there simpler options of more efficient use of the current energy, more efficient production of current energy and, where appropriate, decarbonising our energy systems? If one looks at some of the plausible scenarios of Shell, they show that, by 2050, one could envisage half the world's energy still coming from fossil fuels and half the world's energy coming from a mix of renewable energies. The most contentious part of it, in my opinion, is the use of nuclear power, but that is a public issue. If, indeed, one had realised the Shell scenarios and then pushed them out for the next 50 years as well, one could envisage… where the world would stabilise atmospheric CO2 at about 550 parts per million. Indeed, I think one can actually limit projected changes in climate to a very interesting mix of efficiency and production without just saying that no longer should we have fossil fuels… . [36]
2.104 Professor Karoly's views, in addition to those expressed by Dr Jenkins and Dr Watson, give a valuable insight into the scientific context in which future Kyoto targets will be negotiated. It can be realistically expected that future targets will be substantially lower than those for 2008 to 2012, beginning as early as the second commitment period (2013 or after). This would mean that Australia will need to set its economy on a path to a national emissions total substantially below 108 per cent of 1990 levels during the second commitment period, with an expectation that we may need to reduce emissions to around 70 per cent of 1990 levels by 2030 or possibly earlier.
2.105 The Committee acknowledges that there are a number of areas of scientific uncertainty in relation to climate change. Principle among these are the effect of aerosols on greenhouse forcing, the identification of regional impacts, and the release and sequestration of carbon by soils and plants. Of some debate has been whether the existence of uncertainty suggests either a need to delay abatement action, or the adoption of the precautionary principle, which requires action now while existing uncertainties are further explored. The precautionary principle is specifically recognised in the UNFCCC, and it is a principle the Committee strongly endorses.
2.106 The IPCC states that there are a series of uncertainties, and advocates further work, in relation to:
2.107 The IPCC also explains that the non-linear nature of the climate system will produce `surprises' that are, by their nature, difficult to model:
Future unexpected, large and rapid climate system changes (as have occurred in the past) are, by their nature, difficult to predict. This implies that future climate changes may also involve `surprises'. In particular, these arise from the nonlinear nature of the climate system. When rapidly forced, nonlinear systems are especially subject to unexpected behaviour. Progress can be made by investigating nonlinear processes and subcomponents of the climatic system. Examples of such nonlinear behaviour include rapid circulation changes in the North Atlantic and feedbacks associated with terrestrial ecosystem changes. [38]
2.108 Dr Watson also commented on the difficulties of modelling the impact of the sulphate aerosols. He explained that:
Sulphur actually offsets parts of global warming… firstly, they are particles and therefore they reflect incoming solar radiation; and, secondly, they change the optical properties of clouds... we believe the emissions of sulphur will probably go up for a period of time, largely because of energy needs and the use of coal in Asia - largely India and China - but then they will start to decrease. So, over time, they will be less and less of a cooling offset to the greenhouse gases. [39]
2.109 Dr Watson warned that sulphur emissions, while suspected of having a global cooling effect, were otherwise environmentally damaging because of their role in acid rain:
Sulphur will be controlled independently, in my opinion, of global warming climate policies, largely because of its local and regional effects. Indeed,… our latest projections from a special report are probably slightly less emissions of CO2 than what we had a few years ago, but much lower emissions of sulphur. The end product will be either the same or slightly larger projections of climate change. [40]
2.110 The IPCC's Second Assessment Report also discusses uncertainties in relation to the overall complexity of not merely the global climate system and the forcing effects of multiple gases and particulates, but in relation to the additional stresses provided by human activities:
Although our knowledge has increased significantly during the last decade,… our current understanding of many critical processes is limited; and systems are subject to multiple climatic and nonclimatic stresses, the interactions of which are not always linear or additive. [41]
2.111 The IPCC also cautions that existing studies were limited in scope, and that further work should take account of the difficulty of factoring in very complex dynamic interactions:
Most impact studies have assessed how systems would respond to climate change resulting from an arbitrary doubling of equivalent atmospheric carbon dioxide (CO2) concentrations. Furthermore, very few studies have considered dynamic responses to steadily increasing concentrations of greenhouse gases; fewer still have examined the consequences of increases beyond a doubling of equivalent atmospheric CO2 concentrations or assessed the implications of multiple stress factors. [42]
2.112 It is sometimes said that such uncertainty justifies a delay of greenhouse abatement action. However, the IPCC has strongly established that the balance of evidence suggests a discernible human influence on climate to date, and that greenhouse gas emissions are likely to cause a range of devastating impacts if they increase unchecked.
2.113 Furthermore, the application of the precautionary principle requires that action be taken now. The precautionary principle is recognised in Commonwealth environmental legislation (the Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act), in the National Strategy for Ecologically Sustainable Development, and in the UNFCCC:
… take precautionary measures to anticipate, prevent or minimize the causes of climate change and mitigate its adverse effects. Where there are threats of serious or irreversible damage, lack of full scientific certainty should not be used as a reason for postponing such measures, taking into account that policies and measures to deal with climate change should be cost effective so as to ensure global benefits at the lowest possible cost. [44]
2.114 The IPCC makes a strong argument for the application of the precautionary principle in the face of scientific uncertainty, in its advice to policymakers on adaptation and mitigation. It makes the point that it is important `to consider these uncertainties in the context of information indicating that climateinduced environmental changes cannot be reversed quickly, if at all, due to the long timescales associated with the climate system':
Decisions taken during the next few years may limit the range of possible policy options in the future because high nearterm emissions would require deeper reductions in the future to meet any given target concentration. Delaying action might reduce the overall costs of mitigation because of potential technological advances but could increase both the rate and the eventual magnitude of climate change, hence the adaptation and damage costs.
Policymakers will have to decide to what degree they want to take precautionary measures by mitigating greenhouse gas emissions and enhancing the resilience of vulnerable systems by means of adaptation. Uncertainty does not mean that a nation or the world community cannot position itself better to cope with the broad range of possible climate changes or protect against potentially costly future outcomes. Delaying such measures may leave a nation or the world poorly prepared to deal with adverse changes and may increase the possibility of irreversible or very costly consequences. [45]
2.115 The Committee acknowledges that there exists a small minority of scientists and others who strongly dispute the claims of the IPCC about current and future climate change. Within Australia, a small group was established in mid-2000 under the chairmanship of former Hawke Government minister, the Hon Peter Walsh AO, known as the Lavoisier Group. The Group publicly opposes the IPCC's conclusions about climate change and the Kyoto Protocol.
2.116 The Committee received a submission from the Lavoisier Group in June 2000, some 8 months after the closing date for submissions in 1999, and a few days before its final substantive hearing. Given the lateness of the submission, the Committee was not able to hear evidence from and question the claims of the Group. The submission was primarily a critique by the American meteorologist Professor Richard Lindzen of the submission made to this inquiry by the CSIRO. In order to deal properly with its substantive claims, a response to the submission was sought from the CSIRO. As at the conclusion of its inquiry, the Committee had not received a response from CSIRO, who explained that that they were busy preparing a submission to, and hosting a visit of, the Joint Standing Committee on Treaties' Inquiry into the Kyoto Protocol. The Lavoisier Group submission is publicly available from the secretariat of this Committee. [46]
2.117 A similar submission was made by the consultant Mr Bob Foster. He claimed that:
2.118 In reference to Mr Foster's first claim, the Committee does not support the claim that climate change is an `as yet unsubstantiated threat'. In the Committee's view, the funds dedicated to addressing climate change do not, therefore, constitute an environmental threat as claimed.
2.119 The Committee does not believe that Mr Foster's second claim is tenable. Evidence from a wide range of climate change scientists emphasised that climate change was the result of complex system which included oceans, land and atmospheric factors. Understanding the interaction of such factors is a priority of research, including carbon cycle feedbacks and ocean atmosphere interactions. As Dr Jenkins of the Hadley Centre told the Committee:
The models at the moment - the sort of model we run, the models that you run at CSIRO and BMRC in Australia - couple together the ocean, the atmosphere and the land surface. That needs to be coupled because there are a lot of interactions between those elements of the climate system which are very important in determining feedbacks which can either accentuate or reduce the global warming, or the radiative forcing - the heating effect if you like - of additional man-made gases. So it is very important to link all those parts of the climate system together. [48]
2.120 Similarly, the Committee is not convinced by Mr Foster's claim that climate change forecasting has failed the `hindcast test'. The Committee received evidence from scientists about their efforts to `hindcast' known atmospheric changes using their models. These show that models are having some success in this regard, and that naturally observed changes such as solar radiation and volcano activity cannot account for temperature change of the past 50 years. For example, the Hadley Centre has specifically sought to model backwards, and to incorporate known external events rather than smooth out climate. Their new model, HADCM3, they claimed `has a better representation of climate and climate change than previous models. It has a much better resolution, for example, in the ocean, than most models It does not use so-called flux adjustments to get the climate into a stable condition with low drift':
We use that to try and simulate changes over the past 50 years due to factors which are naturally forced - in other words, largely solar and volcanic - and factors which are human. These are the greenhouse gas rise, the rise in aerosol, changes in ozone and so on. Then we look at the model without any changes at all, either natural or human, to look at the natural internal variability of climate. We find that, only by incorporating all three of those types of changes - in other words, the internal changes, the solar, the volcanic and the human activities - can we really get a good representation of the changes that have occurred over the past 50 years or so. [49]
2.121 Dr Jenkins further explained the results that were arising from this approach:
If we do it just with the natural activity alone, for example the way in which volcanic activity has been quite high over the past two or three decades, and the way that solar changes may have risen to a certain extent but have not been as great as this, we find that cannot give the sort of signal of quite rapid temperature change that has occurred particularly since about 1975. Because the forcing agents have gone down over that period in total that cannot simulate the sort of change that has occurred over that period. But when we include the effect of the human activities increasing greenhouse gases, despite increases in aerosol, we do find we are able to simulate reasonably well the temperature change on a global average basis that has occurred over that period. [50]
2.122 Although a response has not been received from the CSIRO, the Committee did receive evidence relating to one of Professor Lindzen's central criticisms - that satellite data support an argument that `there is no evidence of any warming in the atmosphere', and that there are also problems in the surface record such as variations due to urban concentrations, coverage over oceans and `the fact that much of the warming of the 90s comes from Siberia where, since the breakup of the Soviet Union, data quality control has been, to be generous, inadequate'. [51]
2.123 CSIRO's argument in regard to satellite observations was that:
There is likely to be a real difference between the warming at the earth's surface and the lowest five miles of the atmosphere. This difference was ascribed to three factors: the thinning of the ozone layer, emissions from the Mt Pinatubo volcanic eruption and greenhouse gases.
Additionally, comparing the two sets of measurements is complicated because the observations are different. The ground-based measurements are taken at points usually about 2 m above the earth surface. The satellite observations represent the temperature in a layer of the atmosphere in the region 1,500 – 10,000 m above the Earth's surface.
It should also be noted that the satellite record covers the period from 1979, whereas the ground-based record contains data from about 1860. It is important to have available the longer record in order to evaluate the extent to which recent trends might be due to decadal-scale natural variations in planetary temperature. [52]
2.124 The Hadley Centre maintained that other upper atmosphere records did not show the same conflict with ground records:
You may be aware that particularly in America there has been some controversy as to the extent to which changes in global warming at the surface disagree with measurements of warming made by satellites higher in the atmosphere at about a height of maybe three or five kilometres. What we have done is to not use satellite measurements but measurements from weather balloons and look at the trends in temperature that have occurred since about 1960 to the present day in the atmosphere. That has shown us that the overall trends in temperature in the atmosphere have not been very much different from those at the surface which sees quite a clear warming in the atmosphere reasonably similar to that at the surface overall over that period. [53]
2.125 The Centre was quite open with the Committee about the uncertainty generated by upper atmosphere observations, but stressed that it did not negate the plausibility of the warming shown in the surface record and in the atmosphere:
What we however see is that there are differences between the atmosphere warming and the surface warming in periods of a few years or a decade long which we do not understand. The atmosphere does not warm as quickly as the surface does in those periods. We do not fully understand the reasons for that. We believe there is work to be done in that area to ensure that the models can simulate that correctly. That would then increase our confidence in the models. There is an issue there that still has to be resolved, but it does not negate the fact that the warming at the surface is very robust and that we believe the warming of the atmosphere is quite substantial as well. [54]
2.126 The Hadley Centre also cited work which compared a wide range of evidentiary data on past climate. This data buttressed surface records and suggested that temperature changes over the past 100 years were out of the ordinary:
Another area which is not our work but which I think is a very strong pointer is the work done by Michael Mann at the University of Massachusetts. There is also some work from Keith Briffa and Phil Jones at the University of East Anglia in England. What they have done is to reconstruct paleo records going back over the last thousand years, largely in the Northern Hemisphere. When they put these paleo records from tree rings, ice cores, corals and so on all together to look at the temperature change over the past thousand years, despite the very large uncertainties in these measurements, you can see a reasonably clear trend of very little change or perhaps a small decrease in temperature over that period.
That is until the last 100 years or so, when there is a very significant upward trend over that period, both in the proxy data and in, obviously, the instrumental records that we all know about. So again to see that diagram does make it very clear, if indeed you believe the proxy data of that period, that what is happening over the last 50 or 100 years is unusual in the context of the last thousand years or so. Of course, being unusual does not prove that it is human activities that are to blame, but it does very clearly show that there has been a detection of climate change. On the attribution question, to summarise, as I said at the beginning: the more work we do - not just ourselves but other people as well - the more the pointers are in the direction of a substantial proportion of the temperature rise over the last 50 years being attributable to human activities. [55]
2.127 Dr Robert Watson, Chairman of the IPCC also strongly asserted that observed climatic changes accorded with those expected from global warming:
Indeed, if you ask the question, `What would you expect in a warmer world is caused by greenhouse gases?' you would expect warmer temperatures. We have obviously observed that. You would expect the night time temperatures to have warmed more than day time temperatures; hence there will be less of a diurnal variability. We have observed that. We have observed land warming faster than oceans. We have seen that. We would expect to see more precipitation globally. We have seen that. We would expect to see more precipitation falling in heavy precipitation events. We have observed that. We have also seen what we would call the right latitudinal distribution of temperature changes. So while the models and the data are not in perfect accord there are lots of similarities to suggest that the observed changes in climate have the right fingerprint of human induced activities, not natural phenomena. So we do see a pattern where we would now say the likely reason for the changes in climate are at least in part due to human activities. [56]
2.128 In the Committee's view, climate change scientists have been scrupulously honest about areas where uncertainty exists, and are making credible efforts to reduce that uncertainty through further research. Existing uncertainties (as discussed above) do not lead to a conclusion that concern about both existing and potential climate change is unwarranted or scientifically invalid. IPCC reports are a consensus of hundreds of scientists from around the globe, are exhaustively peer reviewed, and the texts are carefully examined by UNFCCC member governments before they are made public. In such a context, the Committee is confident that human induced climate change is a fact, and that the various IPCC scenarios (given various estimates of emissions, population and economic growth) are plausible. In the face of uncertainty, as noted earlier, the precautionary principle should be followed.
2.129 The Australian Government has also stated that it accepts the scientific consensus established by the IPCC. The Chief Executive of the AGO, Ms Gwen Andrews, emphasised to the Committee that accepting the scientific consensus on climate change was important in developing a long term response to the problem:
This is the time now to start demonstrating that this is a serious matter. Certainly the Government takes very seriously the commitment it has made internationally with regard to the UN framework convention on climate change and its commitment to the Kyoto Protocol and its implementation. The extent of the change that can be achieved in the short term and the targets that have been set are not the end of the story. It is important that the public understand, as Mr Carruthers said, that this is a long term issue and that there will be a long term response….It is important that the public accept the science and the strengthening consensus on the science. [57]
Recommendation 1
The Committee recommends that the Commonwealth Government make a strong public statement on its position on the science of climate change, and initiate an awareness raising campaign to communicate the issue of climate change to the broader community.
2.130 Australia is at the leading edge of global atmospheric and climate change research, with a range of prominent scientists involved in the drafting of IPCC assessments and developing regional climate change models. However, current levels of funding to other areas of research are inadequate to ensure a better understanding of potential climate change in this region, and its impacts on communities, the environment and economic activity.
2.131 Since the late 1980s Australian Governments have spent approximately $55 million on climate change research. In the 1999-2000 budget the Government committed an additional $14 million over four years for the Greenhouse Science Program which aims to improve global, regional and national understanding of climate change, potential impacts on Australia, and options for adaptation and mitigation. [58]
2.132 The Greenhouse Science Advisory Committee (GSAC) recommends the additional application of $10 million per year in their report, Advancing Greenhouse Science Strategy and Business Plan 2000-2005, which was submitted to the Commonwealth Government for consideration in November 1999. The Government has not yet made a decision in regard to these funds, which the GSAC argues would be `a minimum investment to support Australia's national greenhouse commitments. The funds would target gaps in research that need strengthening in the national interest rather than solving all the problems or satisfying all scientific interests'. [59]
2.133 The Committee is strongly of the view that much greater effort and resources need to be directed to understanding the potential impact of climate change on the Australasian region. Such efforts will be crucial to efforts to mitigate potential climate change and adapt to inevitable climate change. They will also help to clarify our national interests in ensuring that a serious global effort to stabilise climate occurs.
2.134 The Director of the CSIRO Atmospheric Research Division, Dr Graeme Pearman, explained the growing demands on Australian scientists:
The amount of science that is required in order to respond to the so-called greenhouse issue today, in the year 2000, is so much different than it was in the year 1990. That is because we are not only required to now continue to develop the underpinning science, which is really mainly pointed at predicting at a regional level the kinds of things that people really need to know, but we are also being asked as a scientific community to provide guidance on issues of sequestration, technological innovation and alternatives of impacts and adaptation and so on. These are areas in which the commitment of the science community has been there but the resources have been very light. So I think there is a question of insufficient resources to do all of those areas. [60]
2.135 Dr Pearman stated that while funding for the underpinning science on regional impacts was probably adequate, he intimated that these extra areas were lacking:
With respect to the underpinning areas of science, the Government has a commitment to maintaining the $4 million a year support to that research over the next triennium. As long as that continues, I think we are reasonably well based, remembering of course that science is becoming, like everything else, dearer to do. [61]
2.136 However, a former CSIRO scientist, Dr Albert Pittock, expressed serious concerns about the ability to continue regionally focused work. He praised CSIRO's efforts to develop global climate models, but added that there was no certainty that such progress could be continued:
The climate model in CSIRO went from non-existence about 15 years ago to now being one of the three or four most reputable in the world. I think we can be very proud of that. It was as the result of a lot of investment by the Government in supercomputing facilities, but that is a big gain for Australia for other reasons. The certainty that we can keep up is not there at the moment. If you come to the more local modelling, the nested modelling and the climate impacts and adaptation work, then Federal funding has pretty well dried up in the last several years. Most of our funding now comes from state governments and some other instrumentalities, so we are particularly getting work in Queensland and New South Wales and to some extent Victoria. It has been a big struggle… . We have, I think, some of the best scientists in the world. The risk assessment vulnerability work is being pioneered by somebody in our lab who has only a temporary position because we do not have the certainty to employ them on a more permanent basis. [62]
2.137 Dr Pearman also admitted that there was a dearth of regionally focused predictions:
There are two levels of impact assessment. There is one level in which you effectively take some scenario - potential future - and you test the response of a component or sector of the society. A lot of that has been done in Australia… . The second level… actually trying to make a real prediction and saying, even with the uncertainties of the projections of the gases and the climate response, can we then say what will actually happen with some uncertainty limits drawn on it. There is virtually none of that being done in this country. [63]
2.138 Dr Pittock argued that funding in this area needed to be increased:
in broad terms it would need to be in the multimillion dollar category, and not just for the CSIRO. There needs to be funding of a lot of regional groups that will have a local knowledge and interest in their own region and be in contact with local stakeholders. [64]
2.139 Professor Garth Paltridge, Director of the Antarctic Cooperative Research Centre, argued that, while basic science was reasonably well resourced in Australia, research on the potential impacts in Australasia was seriously lacking:
What is lacking is good, solid, hard, disciplined research into the impact of climate change on society and on productivity of agriculture and so on. That has always been an area where people tend to wave their hands a lot, but in terms of the actual hard scientific research that is done on the subject of the potential impact of climate change, there is very little indeed that you would say comes out of the reputable scientific journals. [65]
2.140 The Antarctic CRC's Professor William Budd, also said that work was also needed on adaptation, given that irreversible climate change was likely to occur, whatever efforts were made to reduce emissions in the future:
There is another area that also needs attention and that is adaptation. The things that I spoke about with climate change and changes in the ocean appear to be going ahead, even in spite of the best efforts of reducing emissions. If we are concerned about these long term changes then we need to think about adaptation. For example, within Australia what we see is the reduction in rainfall over the long term but, in spite of that, still similar frequencies of floods but greater frequencies of the drier episodes. We need to learn how to adapt to that because this is happening on the decadal and century time scales. It means that these things need to be taken into account in terms of land planning and water usage and all the other agricultural and industrial activities. The main thing is that from the modelling we get a good idea of the time frame in which these things can be expected to develop. [66]
2.141 Professor David Karoly, Director of the Cooperative Research Centre for Southern Hemisphere Meteorology at Monash University, strongly argued that there was a serious gap in research and training opportunities for climate change science in Australian universities:
There have been either direct or indirect reductions in funding for university training groups in atmospheric and climate sciences associated with changes in government policy for university education. This has led to significant reductions in the training of climate specialists and professionals with expertise in climate change and climate change impacts. In fact, it has probably led to a 50 per cent reduction in academic staff in these areas in the last 10 years. This seems to be somewhat inconsistent with an apparent need for increased scientists and professionals with an understanding of climate change and climate change impacts. [67]
2.142 Professor Karoly told the Committee that there is no department of climate or atmospheric science at any university in Australia, and that existing co-operative research centres (CRCs) were also under substantial funding pressures:
A department of atmospheric and climate sciences could or should be established. There have been two significant groups established: the Antarctic CRC that you would be familiar with, in Hobart, has been established with cooperative research centre funding and my own cooperative research centre has been established. My own cooperative research centre [Monash University] will be closing in June this year and the funding for the Antarctic CRC [University of Tasmania] is essentially going to run out in 2003 unless significant changes are made. Those are the two largest groups in climate sciences in Australia at present and both of them are due to close within three years. [68]
2.143 The Committee is very concerned by this evidence. It is of the view that Australia needs to continue to participate in international scientific efforts at a high level, to ensure that a growing body of researchers across a range of disciplines is being trained for future efforts, and in particular, to significantly increase efforts to understand the nature and impact of climate change on this region to adequately inform policy development.
Recommendation 2
The Committee recommends that adequate funding be provided to:
Recommendation 3
The Committee recommends that Australian universities be encouraged to establish departments and courses that focus on atmospheric or climate change science, and that funding be provided to support such initiatives.
Australian Democrats Recommendation 1
The Australian Democrats recommend that a minimum of $100 million in funding should be provided over the next four years for climate change science.
2.144 The Committee accepts the growing consensus that human activity is leading to increasing atmospheric concentrations of greenhouse gases with significant changes to global climate predicted as a result.
2.145 Notwithstanding existing uncertainties, it is clear that predicted climate change will have severe implications for Australia, which is already subject to drought, El Nino/La Nina, tropical cyclones and extremes of climate. Coastal communities and low-lying areas will be particularly vulnerable and changes to temperature and rainfall could affect biodiversity and ecological communities, agricultural systems, flooding patterns and river flows, and worsen drought and dryland salinity. Increases in sea temperatures could cause irreversible damage to coral reefs.
2.146 Australia has a strong dependence on climate-vulnerable industries such as agriculture and tourism, and is the custodian of a vast array of unique biodiversity, much of which is recognised in national parks and World Heritage Listed areas.
2.147 Scientists have already identified emissions reduction pathways that would stabilise the global climate system at global CO2 concentrations of around 550 parts per million, which could pre-empt much damaging climate change. While challenging, these reductions are achievable if concerted global efforts begin now.
2.148 In the Committee's view, Australia has a clear national interest in seeing the global community work towards stabilising the climate system. If predicted climate change does occur, it will have significant social, economic and environmental implications for Australia.
2.149 The emission reduction pathways outlined by scientists and the IPCC, to stabilise atmospheric concentrations of greenhouse gases, also indicate a need for Australia to begin long term planning. Such pathways, which may require a global emissions reduction of 70 per cent within 150 to 200 years, are likely to be reflected in future global responses.
2.150 The Committee concludes that the balance of evidence strongly suggests that Australia will be very negatively affected by climate change given the size of its land mass and its long coastline, its current extremes of climate, its vulnerability to cyclones and the El Nino/La Nina cycle, its existing problems with soil salinity, and its economic dependence on agriculture and tourism.
[1] Intergovernmental Panel on Climate Change, Special Report on Emission Scenarios, A Special Report of Working Group III, May 2000.
[2] Dr Barrie Pittock, Submission 220, p 4.
[3] Dr Barrie Pittock, Submission 220, p 4.
[4] Dr Bryan Jenkins, Proof Committee Hansard, Perth, 17 April 2000, p 454.
[5] Dr Barrie Pittock, Submission 220, p 4.
[6] Dr Barrie Pittock, Submission 220, pp 5-6.
[7] Mr Michael Rae, Proof Committee Hansard, Sydney, 23 March 2000, p 445.
[8] CSIRO, Submission 206, p 2470.
[9] CSIRO, Submission 206, p 2470.
[10] Official Committee Hansard, Canberra, 9 March 2000, p 36.
[11] CSIRO, Submission 206, p 2470-71.
[12] Proof Committee Hansard, Canberra, 22 June 2000, p 743.
[13] CSIRO, Submission 206, p 2471.
[14] CSIRO, Submission 206, p 2471.
[15] CSIRO, Submission 206, p 2472.
[16] CSIRO, Submission 206, p 2472.
[17] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clauses 4.6-4.8.
[18] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, Figure 1.
[19] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clauses 4.16, Figure 1.
[20] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 4.18.
[21] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 4.13.
[22] CSIRO, Submission 206, p 2459.
[23] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 4.14.
[24] The Australian Greenhouse Office, National Greenhouse Gas Inventory: Analysis of Trends and Greenhouse Indicators 1990-98, pp 9, 54-55.
[25] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 4.6.
[26] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 4.10.
[27] Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 4.16.
[28] Official Committee Hansard, Canberra, 9 March 2000, p 25.
[29] Official Committee Hansard, Canberra, 9 March 2000, p 25.
[30] Official Committee Hansard, Canberra, 9 March 2000, p 40.
[31] Official Committee Hansard, Canberra, 9 March 2000, p 40.
[32] Official Committee Hansard, Canberra, 9 March 2000, p 26.
[33] IPCC Working Group 1, Summary for Policymakers: The Science of Climate Change, http://www.ipcc.ch/pub/arsum.htm (01/09/00), p 1.
[34] Official Committee Hansard, Canberra, 9 March 2000, p 40.
[35] Official Committee Hansard, Canberra, 9 March 2000, pp 43-44.
[36] Proof Committee Hansard, Canberra, 9 March 2000, p 38.
[37] IPCC Working Group 1, Summary for Policymakers: The Science of Climate Change, http://www.ipcc.ch/pub/sarsum1.htm, (01/09/00).
[38] IPCC Working Group 1, Summary for Policymakers: The Science of Climate Change, http://www.ipcc.ch/pub/sarsum1.htm (01/09/00).
[39] Official Committee Hansard, Canberra, 9 March 2000, p 37.
[40] Official Committee Hansard, Canberra, 9 March 2000, p 37.
[41] IPCC Working Group II, Summary for Policymakers: Scientific-Technical Analyses of Impacts, Adaptations and Mitigation of Climate Change, Part 3.
[42] IPCC Working Group II, Summary for Policymakers: Scientific-Technical Analyses of Impacts, Adaptations and Mitigation of Climate Change, Part 3..
[43] Environmental Protection and Biodiversity Conservation Act 1999, section 3A, p 4.
[44] Cited in Intergovernmental Panel on Climate Change, IPCC Second Assessment Synthesis of Scientific-Technical Information Relevant to Interpreting Article 2 of the UN Framework Convention on Climate Change, clause 1.10.
[45] IPCC Working Group II, Summary for Policymakers: Scientific-Technical Analyses of Impacts, Adaptations and Mitigation of Climate Change, Part 2.
[46] The Lavoisier Group, Submission 222.
[47] Bob Foster Consultancy, Submission 36.
[48] Official Committee Hansard, Canberra, 9 March 2000, p 23.
[49] Official Committee Hansard, Canberra, 9 March 2000, p 21.
[50] Official Committee Hansard, Canberra, 9 March 2000, p 21.
[51] The Lavoisier Group, Submission 222, pp 2870, 2874.
[52] CSIRO, Submission 206, p 2462.
[53] Dr Geoff Jenkins, Official Committee Hansard, Canberra, 9 March 2000, pp 23-24.
[54] Dr Geoff Jenkins, Official Committee Hansard, Canberra, 9 March 2000, p 24.
[55] Dr Geoff Jenkins, Official Committee Hansard, Canberra, 9 March 2000, p 22.
[56] Official Committee Hansard, Canberra, 9 march 2000, p 34.
[57] Official Committee Hansard, Canberra, 22 June 2000, p 705.
[58] The Australian Greenhouse Office, Submission 169, p 1703; and Greenhouse Science Advisory Committee, Advancing Greenhouse Science Strategy and Business Plan 2000-2005, November 1999, p 5.
[59] Greenhouse Science Advisory Committee, Advancing Greenhouse Science Strategy and Business Plan 2000-2005, November 1999, p 2.
[60] Proof Committee Hansard, Melbourne, 20 March 2000, p 122.
[61] Proof Committee Hansard, Melbourne, 20 March 2000, p 122.
[62] Proof Committee Hansard, Canberra, 22 June 2000, p 747.
[63] Proof Committee Hansard, Melbourne, 20 March 2000, p 133.
[64] Proof Committee Hansard, Canberra, 22 June 2000, p 747.
[65] Proof Committee Hansard, Hobart, 5 May 2000, p E495.
[66] Proof Committee Hansard, Hobart, 5 May 2000, p E495.
[67] Proof Committee Hansard, Canberra, 9 March 2000, p 40.
[68] Proof Committee Hansard, Canberra, 9 March 2000, p 41.
