Australasian Journal of Ecotoxicology Vol. 15, pp. 1-4, 2009 Ecotoxicology and a high C02 world Jeffree o p i n i o n p i e c e Climate Change, Ocean Acidification and Marine Ecotoxicology: How to Migrate to Greater Policy Relevance and Impact Ross Jeffree Radioecology Laboratory, IAEA Marine Environment Laboratories, Monaco. Manuscript received, 4/5/2009; accepted, 10/6/2009. The year of 2009 marks the 150th anniversary of the publication of the Origin of Species by Charles Darwin, where he explained the origins of biodiversity. And now only one and a half centuries on we repeatedly hear the death knell for substantial proportions of that very biodiversity; not necessarily from the effects of the chemical pollutants that we typically study as ecotoxicologists, but from the levels of carbon dioxide (CO2) emissions into the atmosphere. If ecotoxicologists want to remain relevant to the most important environmental issues and challenges then they need to find ways to scientifically face the ‘elephant in the living room’ viz. climate change and related effects of CO2. But how do we migrate to there from where we currently sit as ecotoxicologists? Fortuitously for an ecotoxicologist/ radioecologist, the effects of CO2 on oceans has been an area of focus here at IAEA MEL, where the clear chemical outcome is one of increasing acidity, that is quickly being recognised as an over-arching and global chemical driver of changes to marine biodiversity (EPOCA 2009). Particularly as an Australian it is hard to imagine that the Great Barrier Reef may start to disappear in 40-50 years, but this is the risk we now face. This article is concerned with one possible answer to this question of how to adapt ecotoxicological studies to also consider ongoing changes in climate and marine chemistry with climate change. Another goal is to find some leverage points so that our science may effectively influence both public opinion and the political will to adequately mitigate carbon emissions to limit reductions in biodiversity. The Australasian regional economic imperatives to do so by removing the links between economic activity and greenhouse gas emissions have been strongly pointed out recently in the Garnaut Report (2008). Alternatively we are left to only engage in ‘hand wringing’ environmental concern, albeit relatively well informed. Overview of ocean acidification Ocean acidification (OA) is a rapidly evolving area of environmental science and its potential effects on marine ecosystems are well reviewed by Guinotte and Fabry (2008). In brief, it is the process of declining pH in seawater that results from the ocean’s absorption of anthropogenic CO2 from the atmosphere. The average pH of the surface ocean has already declined by 0.1 of a pH unit to 8.1 since the beginning of the industrial revolution and is predicted to decline by another 0.2 to 0.4 units by 2100. The carbonate ion concentration has also declined by more than 10% *Author for correspondence, email: [email protected] already relative to the pre-industrial level. The carbonate concentration in seawater is the prime determiner of whether biogenic calcium carbonate either precipitates or dissolves; hence there is growing concern for those organisms with shells of calcium carbonate, particularly those made of aragonite that dissolves more readily than calcite. This growing concern is already well justified by the experimental studies undertaken so far of OA effects on calcifiers, for realistic carbon emission scenarios provided by the Intergovernmental Panel on Climate Change (IPCC 2007). The majority of corals tested reduce calcification, by up to 56% (Kleypas et al. 2006), an effect that can be enhanced by increased temperature (Reynaud et al. 2003). A more recent study suggests that when atmospheric CO2 doubles to 560 ppm almost all coral reefs will cease to grow and start to dissolve (Silverman et al. 2009). Thus, there is great concern for the future of coral reefs and the ecosystems that depend on the physical habitat that they provide. Calcification rates in commercially valuable molluscs decrease linearly with increasing CO2 in short-term exposures, with adverse effects also observed on early life stages of several species of shellfish. Important species of calcareous phytoplankton called coccolithophores show reduced calcification at lower pH but there is a species-dependent response to OA, and biogeochemical cycles may also be affected (from summary by Martin et al. 2008; Gazeau et al. 2007; Parker et al. 2009; Talmage and Gobler 2009). Part of the answer, I believe, is found in consideration of the Stern Review: The Economics of Climate Change (2007) and the leverage it has already had on shifting governmental policy with respect to mitigating carbon emissions. The Garnaut Report (2008) has also supported this position in the national Australian context. The Stern Review has convincingly demonstrated the economic costs of climate change, the costs and benefits of action to reduce the emissions of greenhouse gases, and the economic benefits of strong early action on their reductions, i.e. within the next 10-20 years. The voluminous and compelling science of climate change has undergirded this economic assessment. But it was finally the economic analysis per se which demonstrated that timely mitigation is a highly productive economic investment that has ultimately persuaded Government to seriously move now on the climate change issue. The Stern Review also mentions OA and the “possible adverse consequences on fish stocks”. As ‘profit and loss’ economic arguments are eminently influential in government policy formulation and decision-making at the highest level, then I would propose that part of the answer to the question posed above is as follows. 1 Australasian Journal of Ecotoxicology Ecotoxicology and a high C02 world Clearly now, it is more important to know about the imminent future global and Australasian regional environment, given the accelerating rates of climate change. The mathematically modelled future is our best window to the physical and chemical conditions that will be faced by marine biodiversity. The models can be repeatedly revised as more information comes to light in this rapidly emerging area of scientific investigation. The Intergovernmental Panel on Climate Change is the premier international body to provide the best advice on future climate scenarios. Based on current knowledge, the modelling and empirical evaluation of biological and ecological outcomes that are needed include the following, with an Australasian focus: Scanning for OA effects in a broader range of marine taxa of commercial value and those keystone species that support them, to identify those that will suffer most in the acidified ocean of the future; collaborations with natural resource economists to begin to value the scale of possible regional economic losses associated with seafood depletions due to OA and the provision of this advice on potential revenue losses to regional governments and relevant international organisations that are also active in the region, e.g., FAO Fisheries, UNEP; IOCUNESCO; UNDP; engagement with the fisheries and aquaculture industries to motivate them as a powerful group with a strong vested interest in lobbying government on carbon emission reduction targets. This is particularly relevant as internationally the aquaculture industry is positioning itself with a ‘blue revolution’ in aquaculture, as the aquatic analogue of the agricultural ‘green revolution’ that began in the 1960s, to provide a major part of the projected shortfall in food production from agriculture and the attendant food crisis associated with increases in world population over the coming decades (Sachs 2007); comparisons of dissolution or reduced calcification rates in commercially valuable shellfish, including those from developing countries, to identify any differential rates so as to rank species in their relative sensitivity to OA, hence providing the aquaculture industry with advice on the more OA-resilient species for adaptive responses; and modelled predictions on what cuts in carbon emissions are required to mitigate negative impacts on seafoods, beginning with calcifiers for which there is a clear and specific mechanism of detriment already identified. The OA-related ecotoxicological effects already demonstrated experimentally, based on predicted pH values, appear to eclipse most other current concerns in marine ecotoxicology. If this is the case, then appropriate re-focussing of expertise in ecotoxicology should be directed to undertaking the science needed to better predict the extent of OA impacts on marine diversity to the end of the century. 2 Vol. 15, pp. 1-4, 2009 Jeffree What is being contributed by IAEA MEL Research programme: Future coastal marine environments and the sustainability of fisheries and biodiversity Our research programme has specifically focussed on areas in which there is currently less scientific activity compared to other areas under investigation (i.e. corals and other calcifiers), which integrate with ongoing studies in ecotoxicology and radioecology, and which respond to the socio-economic priorities of IAEA Member States. There is increasing societal concern about the likely effects of climate change and increasing levels of various contaminants including carbon dioxide on the ocean, its fisheries and biodiversity. Mathematical modelling in combination with radiotracer studies on marine organisms that are valued as seafoods can provide information on what the future holds. This information can support better environmental management decisions by Member States with regard to both mitigation of carbon emission rates and societal adaptation to future marine environments. A series of experimental radiotracer studies is continuing on various species of commercial seafoods to provide a first assessment of the potential impacts of ocean acidification on their biological processes. The fish species chosen were seabream (Sparus aurata) and seabass (Dicentrarchus labrax), that are the most important species for finfish aquaculture along the Mediterranean and Eastern Atlantic coasts, with global production of 108 000 tons of sea bream ($595 million US) and 60 000 tons of sea bass ($386 million) in 2006. The cephalopod species chosen is the cuttlefish (Sepia officinalis). Cephalopod catch was more than 50 000 tonnes in the Mediterranean according to FAO (2000) and is becoming more important as finfish catches decline. Also the early life stages of both fish and cuttlefish were chosen as they may be the most sensitive stages. The experimental parameters we used were based on projected scenarios of ocean pH and temperature, as derived from various models of carbon emissions to the year 2100, that had been previously predicted by IAEA-MEL staff (Orr et al. 2005). We used a suite of radiotracers to assess short-term rates of incorporation of essential elements such as Ca and Zn, and trace contaminants also expected to increase in the future with industrial growth and increased nuclear power production to mitigate carbon emissions. Our first results on the eggs and larvae of seabream and cuttlefish have shown both morphological and physiological impacts of ocean acidification on these two commercially important taxa, and also the increasing accumulation of some metal contaminants (Lacoue-Labarthe et al. 2009). Other recently-published studies of the effects of OA on marine fish have included impairment to olfactory discrimination and homing ability and enhancement of otolith growth (Munday et al. 2009; Checkley et al. 2009). Radiotracer studies on commercial seafoods can identify negative effects of OA on their viability or rates of increase. These effects can be valued economically, in the context of what their decline would represent to the future profits of the aquaculture and fisheries industries, reductions in gross national products, etc. Such Australasian Journal of Ecotoxicology Ecotoxicology and a high C02 world information has greater potential to readily enter economic valuation so as to clarify the full social cost of carbon, and so support better-informed decision-making in countries on the management of the marine environment. A new Centre of Excellence in Environment and Economics To constructively move forward with this strategic approach we have recently developed a new working group within the Monaco scientific and economic community. To begin to develop links between environmental science and economics, the Group plans to hold a first Workshop in Monaco entitled Bridging the Gap between Ocean Acidification Impacts and Economic Valuation, with financial support from the Prince Albert II Foundation. The objectives of the Workshop are as follows: To bring together the leading scientific investigators of ocean acidification and natural resource economics, to discuss both what is currently known about ocean acidification, its biological effects and its predicted global impacts, and ways to evaluate its potential economic costs to fisheries, aquaculture and tourism. Through this interaction between scientists and economists to develop plausible scenarios of the scales of the costs associated with ocean acidification, as related to different carbon emission predictions from the IPCC. To provide a venue where high-level governmental policy makers, relevant international organisations (e.g. FAO Fisheries, UNEP, UNDP, IOC) and private industry (e.g. Aquaculture, Fisheries and Tourism) can be advised in a timely fashion of the likely magnitudes of these societal costs associated with ocean acidification, that are in addition to those carbon costs previously estimated for climate change scenarios (i.e. the Stern Review). To support the more rapid de-carbonisation of the world economy through better valuation of the full social costs of carbon emissions and the benefits of policy actions for their reductions. We have also begun operationally with a preliminary assessment of future economic impacts of ocean acidification on the Mediterranean seafood industry (Hilmi et al. 2009). Within the Australian context it is obvious that the demise of the Great Barrier Reef would have very serious negative economic consequences for the tourism and associated industries, and it is now important to economically value its loss. Whereas there is current political interest in Australia to protect ‘trade exposed industries’ such as coal production from carbon trading, we should also draw political attention to those ‘climate change industries’ like coral reef-based tourism that will suffer from delaying action on carbon mitigation agreements and mechanisms at the international level. Vol. 15, pp. 1-4, 2009 Jeffree Summary and conclusion Marine ecotoxicologists can further enhance their environmental and societal relevance by embracing the issue of ocean acidification in their experimental studies. Because of the enhanced importance of seafood consumption for the lives and livelihoods of increasing coastal populations in Asia, the predicted detriments to marine biodiversity from ocean acidification are particularly important. The socioeconomic significance of the potential impacts of OA warrants that research should be re-focussed to acknowledge CO2 as a critical contaminant, that will probably also affect the impacts of many other contaminants in the marine environment in the near future. We should also seek out opportunities to collaborate with natural resource economists so that the science that we undertake has the potential for greater relevance in political decision-making with regard to carbon mitigation. ACKNOWLEDGEMENTS Two anonymous referees are thanked for their comments that helped to improve the paper. REFERENCES Checkley Jr DM, Dickson AG, Takahashi M, Radich A, Eisenkolb N and Asch R. 2009. Elevated CO2 enhances otolith growth in young fish. Science 324, 1683. 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