IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group II: Impacts, Adaptation and Vulnerability

16.7.2 Impacts and adaptation

  • A decade ago, many small islands were the subject of vulnerability assessments to climate change. Such assessments were based on simplistic scenarios, with an emphasis on sea-level rise, and the application of a common methodology that was applied to many small islands throughout the world. The results were initially summarised in the IPCC Second Assessment Report (IPCC, 1996), with later and more comprehensive studies being reported in the TAR. Since then the momentum for vulnerability and impact studies appears to have declined, such that in the present assessment we can cite few robust investigations of climate change impacts on small islands using more recent scenarios and more precise projections. Developing a renewed international agenda to assess the vulnerability of small islands, based on the most recent projections and newly available tools, would provide small islands with a firmer basis for future planning.
  • Our assessment has identified several key areas and gaps that are under-represented in contemporary research on the impacts of climate change on small islands. These include:-
  • the role of coastal ecosystems such as mangroves, coral reefs and beaches in providing natural defences against sea-level rise and storms;
  • establishing the response of terrestrial upland and inland ecosystems, including woodlands, grasslands and wetlands, to changes in mean temperature and rainfall and extremes;
  • considering how commercial agriculture, forestry and fisheries, as well as subsistence agriculture, artisanal fishing and food security, will be impacted by the combination of climate change and non-climate-related forces;
  • expanding knowledge of climate-sensitive diseases in small islands through national and regional research, not only for vector-borne diseases but for skin, respiratory and water-borne diseases;
  • given the diversity of ‘island types’ and locations, identifying the most vulnerable systems and sectors, according to island type.
  • In contrast to the other regions in this assessment, there is also an absence of demographic and socio-economic scenarios and projections for small islands. Nor have future changes in socio-economic conditions on small islands been well presented in existing assessments (e.g., IPCC, 2001; Millennium Ecosystem Assessment, 2003). Developing more appropriate scenarios for assessing the impacts of climate change on the human systems of small islands remains a challenge.
  • Methods to project exposures to climate stimuli and non-climate stresses at finer spatial scales should be developed, in order to further improve understanding of the potential consequences of climate variability and change, particularly extreme weather and climate events. In addition, further resources need to be applied to the development of appropriate methods and tools for identifying critical thresholds for both bio-geophysical and socio-economic systems on islands.
  • Our evaluation of adaptation in small islands suggests that the understanding of adaptive capacity and adaptation options is still at an early stage of development. Although several potential constraints on, as well as opportunities for, adaptation were identified, two features became apparent. First, the application of some adaptation measures commonly used in continental situations poses particular challenges in a small island setting. Examples include insurance, where there is a small population pool although the propensity for natural disasters is high and where local resilience may be undermined by economic liberalisation. Second, some adaptation measures appear to be advocated particularly for small islands and not elsewhere. Examples include emigration and resettlement, the use of traditional knowledge, and responses to short-term extreme events as a model for adaptation to climate change. Results of studies of each of these issues suggest some ambiguities and the need for further research, including the assessment of practical outcomes that enhance adaptive capacity and resilience.
  • With respect to technical measures, countries may wish to pay closer attention to the traditional technologies and skills that have allowed island communities to cope successfully with climate variability in the past. However, as it is uncertain whether the traditional technologies and skills are sufficient to reduce the adverse consequence of climate change, these may need to be combined with modern knowledge and technologies, where appropriate.
  • Local capacity should be strengthened in the areas of environmental assessment and management, modelling, economic and social development planning related to climate change, and adaptation and mitigation in small islands. This objective should be pursued through the application of participatory approaches to capacity building and institutional change.
  • Access to reliable and affordable energy is a vital element in most small islands, where the high cost of energy is regarded as a barrier to the goal of attaining sustainable development. Research and development into energy options appropriate to small islands could help in both adaptation and mitigation strategies whilst also enhancing the prospect of achieving sustainable growth.