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Submitted by the
Grantham Institute for Climate Change at
Summary · There is a dangerous perception in the
impacts and policy communities that the climate projection problem is
essentially solved. However, there can at present be little confidence in
projections for · Moving adaptation higher on the agenda is a necessity but must not deflect from the priority for mitigation. Both are needed and adaptation strategies also need to take into account mitigation priorities, particularly in terms of agriculture and water. · The quality of information available
for adaptation decisions in the · Given the level of confidence that can
at present be had in regional climate projections over the next few decades,
the best adaptive response can often be to build in more resilience. We also suggest that plans for adapting the · Uncertainties in climate projections are compounded by uncertainty about the specific responses of biogeochemical cycles, species and ecosystems to climatic stress and novel climatic conditions and the impact of feedbacks between the different components of the entire system. · The interaction of climate change with
habitat loss and agricultural intensification will be crucial for the
persistence of species and ecosystems. · Some issues cannot be managed effectively at a regional or even national scale and a European-scale response will be required. Government machinery and incentives will need to be structured carefully to avoid sub-optimal fragmented responses, either geographically or sectorally. · The big challenge for climate science is to provide useful predictions of regional climate change statistics for the next few decades. Far-sighted research that explores the complex interactions between climate, society and ecosystems and their implications for adaptation is also required. Climate projections 1. There is a dangerous perception in the impacts and policy communities that the climate projection problem is essentially solved and that downscaling from current global climate models provides a firm basis for determining impacts and adaptation requirements at a regional level. 2. In reality, there is a cascade of confidence in climate projections. There is indeed very high confidence in the occurrence of climate change due to human emissions of greenhouse gases and the associated nature of planetary scale trends in temperature. There is some confidence in trends for precipitation on the same scale. There is moderate confidence in aspects of continental scale climate change projections. 3. There can at present be little confidence
in projections for 4. These failings cannot be compensated by
any downscaling or statistical procedures, however complex, and will be
reflected in uncertainties on all scales.
So for the Adaptation and mitigation: both are needed 5. Global climate models, as assessed by IPCC, suggest little dependence of climate change on the actual emission scenario until after 2030. In other words, mitigation action cannot now significantly affect near term climate change impacts due to the inertia in the climate system. Further climate change is therefore inevitable and adaptation to it is essential. 6. Moving adaptation higher on the agenda is therefore a necessity but must not deflect from the priority for mitigation. Under current circumstances both are needed in order to cope with inevitable change to come but also to limit the extent of further change that may be beyond the capacity of human and natural systems to adapt without major dislocations to society, the economy and the environment. The local adaptation to climate change must be considered in the context of the global requirement to mitigate the change. 7. Adaptation capacity will be constrained by a variety of factors including: the inherent characteristics of the systems under consideration; linkages and interdependencies across spatial scales and systems; uncertainties in future climate and in system responses to those climate changes; political and institutional hierarchies; and by resource availability. 8. There can also be mal-adaptation: hotter buildings in summer must be countered through better design rather than more air conditioners, at least until electricity supplies have been decarbonised. Adaptation strategies in agricultural systems need to consider greenhouse gas fluxes as well as the maintenance of production. The adaptation/mitigation mix 9. Mitigation action is by its nature global. One key determinant of anthropogenic climate change is the cumulative level of global emissions of carbon dioxide into the atmosphere, not the annual or even cumulative emissions of a single country. The contributions to climate change of other, often shorter-lived but more powerful greenhouse gases as well as that of aerosols are also important. Indeed, agricultural emissions of methane and nitrous oxide may prove to be a long-term constraint on how much we can reduce greenhouse gas emissions. 10. By contrast, adaptation is to a far greater degree influenced by local or national level decisions and actions. The bulk of adaptation costs and benefits are likely to fall on the same generation and within a defined geographical region, rather than globally. There are, however, important examples of externalities in adaptation - both potentially positive and negative. For example, the result of a particular approach to minimizing flood risk or enhancing coastal defense in one area may be simply to shift the risk elsewhere. 11. The time dimension of mitigation and adaptation actions must be considered carefully. Mitigation and adaptation are likely to differ in terms of the timing of their costs and the flow of their benefits, both of which remain subject to considerable uncertainties. Given this, we need to pursue both mitigation and adaptation policies, aiming iteratively to determine an appropriate mix of mitigation and adaptation over time, informed by new information about rates of climate change and impact and from current and future research programmes. 12. Water resources are an important example of where
adaptation and mitigation need to be considered together. The water industry is
a major user of energy in the 13. Both mitigation and adaptation efforts can have perverse outcomes and need to be carefully and broadly assessed for costs, benefits and risks. For example, certain low carbon energy technologies result in incursions into intact natural habitats leading to further deforestation, degradation and associated emissions. Transport infrastructure designed to serve such installations can disrupt ecosystems, release green carbon, reduce resilience and disrupt the natural processes that enable species to adapt to and persist in the face of change. Large-scale land use change, associated with managing flood risk and water quality, also may have implications for climate feedbacks, for example release of carbon from drained peatlands. Climate information for Adaptation Decisions 14. The quality of information available for
adaptation decisions in the 15. The 25km scale climate change information provided by UKCP is indicative to the extent that it reflects the large-scale changes modified by local conditions. There is no climate change information in the 5km data provided by UKCP beyond that at 25km. All that can be produced is a range of examples of local climates consistent with current larger-scale model projections. The confidence in the climate change information also depends strongly on the variable under discussion. For example, for UKCP no projections are given for regional or local wind changes. 16. Given the level of confidence that can at
present be had in regional projections over the next few decades, the best
adaptive response can often be to build in more resilience. We also suggest that plans for adapting the Relationship between climate and other types of environmental change 17. Climate change generally impacts on the
natural environment in consort with other pressures on it. A wide-ranging,
holistic approach is therefore required to adaptation which may currently be
lacking. For example, current 18. Uncertainties in climate projections are
compounded by uncertainty about the specific responses of biogeochemical
cycles, species and ecosystems to climatic stress and novel climatic conditions
and the impact of feedbacks between the different components of the entire
system. This raises questions about the
extent to which species and ecosystems are able to adapt without anthropogenic
assistance. A report to the LWEC board by Grantham-associated researchers
highlighted the weak evidence base in the scientific literature concerning the
potential for Land management 19. Agricultural land management is central to climate change adaptation. For example, current activity in the water industry is looking into manipulating land use to improve river water quality and ecology, to reduce flood water generation and to increase flood water storage. The potential gains to be made, in terms of balancing human needs and environmental needs under pressures of climate change, are clearly large. 20. However, climate change introduces complexity which has not yet been tackled adequately: research has focused on direct effects of climate change (i.e. changes in river flows due to rainfall and temperature changes). Less direct effects, such as impacts of the hydrological cycle due to vegetation and soil structure, are potentially crucial, but have not yet been studied. 21. Much 22. Within the Water resources 23. Overall, the future balance of water supply and environmental needs for water is complex, depending on interacting social, political, economic and technological factors as well as climate change. Relevant factors in the water industry include: social acceptability of non-potable water supply; social acceptability of water recycling; social attitudes towards cheap water supply versus environmental protection; effects of water metering and other demand management measures; cost of energy; trends in water pollution and associated treatment costs; population growth and distribution; desalination technology (at present high energy cost, although there is potential for use of renewable sources). 24. The complexity of the problem requires
future scenarios to be developed which account for the interactions. This has already
been done for flood risk to some degree (Foresight), but not for water resource
and environmental planning. In the 25. However, the Resilience of the freshwater environment to climate change 26. In general, natural surface water systems in
the 27. There is currently little research on how society values the natural freshwater environment versus quality and cheapness of water supply and other human uses. However, EU directives on environmental protection - notably the Water Framework Directive (WFD) and all the daughter Directives which it covers - imply that environmental protection will be a primary objective of climate change adaptation. Although the WFD is clear on the fact that good ecological status should be aimed for in general, what constitutes 'good' is not clear. 28. The freshwater environment should be allowed to adapt naturally to climate change, as far as possible given the human needs for water. This does not mean "do nothing"; rather it means minimizing effects of direct human influences to allow more natural conditions (e.g. abstraction management, development control), or in some cases controlling direct human influences to simulate natural conditions (reservoir releases to simulate natural flow regime; wetland creation as part of flood management). Ecosystems and biodiversity 29. The interaction of climate change with
habitat loss and agricultural intensification will be crucial for the
persistence of species and ecosystems.
In previous episodes of climate change in the Earth's history, species
and ecosystems largely responded through shifts in altitude and/or latitude or
through persisting in small refugual areas.
In the modern 30. Land management will also play a crucial role in the persistence of biodiversity under climate change. Patterns of land use determine the isolation of natural ecosystems and greatly influence the ability of species to disperse from one habitat to another, a process that will be needed if climate change results in the movement of species' climatic niches. Designing landscapes to maximize connectivity should be an important component of climate adaptation measures. 31. Climate change is an issue that is much
wider than the 32. To date, conservation policies have
prioritized limiting spread of species into and out of the 33. Such cross-border effects of climate change cannot be effectively managed at the national scale. Cross-European collaboration presents opportunities for planning and implementation at a much broader scale which can be extremely beneficial. However, effective adaptation at the European scale will involve compromises at the national scale and this needs to be discussed and understood within and among all EU states before such an approach is adopted and implemented. 34. There is also potential that interactions and feedbacks will occur among different systems. For example, alterations to the freshwater systems may have strong impacts on terrestrial protected area systems by increasing the frequency of floods and/or droughts, and through long-term changes to water table levels. 35. In order to maintain ecosystem functions
in an uncertain future, we should ensure that ecosystems are as resilient as
possible. Those systems that are
restricted, homogeneous and isolated are likely to be less resilient. It follows that Machinery of Government 36. Based on the above, there is a clear risk of
sub-optimal adaptation responses for a number of reasons. One risk is that Government
places too much confidence in particular climate projections and planning runs
ahead of our knowledge of both the future climate and the response of other key
systems to climate change. This might lock in inappropriate adaptation
strategies and increase climate costs.
Another risk might be that the way in which UK Government is structured
and in which resources are allocated might act as a disincentive to synergistic
action across regions and/or sectors.
Consideration therefore needs to be given to how the Government can
increase the incentives for the relevant Departments and agencies to work more
effectively together to address the adaptation challenges we face, both at a Research Challenges 37. The big challenge for climate science in the next decade is to provide useful predictions of regional climate change statistics for the next few decades so as to provide a basis for more advanced adaptation strategies. 38. Far-sighted research is needed which explores the complex interactions between climate, society and ecosystems and their implications for adaptation. The ability to predict where, when and how often ecological or other thresholds (e.g. flood risk) will be passed under climate change is beyond our current knowledge and the present generation of scientific models.
26 October 2009
[1] Mace, G.M., Chevin, L-M, Roberts, M. and Coulson T. (2009) The biological limits to adaptation: What is known and not known about genetic and phenotypic responses to rapid and extreme environmental change Contract no R8/H12/109 - Living with Environmental Change pilot review scheme - Objective B Scoping Study
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