6.8 Key uncertainties, research gaps and priorities

This assessment shows that the level of knowledge is not consistent with the potential severity of the problem of climate change and coastal zones. While knowledge is not adequate in any aspect, uncertainty increases as we move from the natural sub-system to the human sub-system, with the largest uncertainties concerning their interaction (Figure 6.1). An understanding of this interaction is critical to a comprehensive understanding of human vulnerability in coastal and low-lying areas and should include the role of institutional adaptation and public participation (Section 6.4.3). While research is required at all scales, improved understanding at the physiographic unit scale (e.g., coastal cells, deltas or estuaries) would have particular benefits, and support adaptation to climate change and wider coastal management. There also remains a strong focus on sea-level rise, which needs to be broadened to include all the climate drivers in the coastal zone (Table 6.2). Finally, any response to climate change has to address the other non-climate drivers of coastal change in terms of understanding potential impacts and responses, as they will interact with climate change. As recognised in earlier IPCC assessments and the Millennium Ecosystem and LOICZ Assessments (Agardy et al., 2005; Crossland et al., 2005), these other drivers generally exacerbate the impacts of climate change.

The following research initiatives would substantially reduce these uncertainties and increase the effectiveness and science base of long-term coastal planning and policy development.

Establishing better baselines of actual coastal changes, including local factors and sea-level rise, and the climate and non-climate drivers, through additional observations and expanded monitoring. This would help to better establish the causal links between climate and coastal change which tend to remain inferred rather than observed (Section 6.2.5), and support model development.

• Improving predictive capacity for future coastal change due to climate and other drivers, through field observations, experiments and model development. A particular challenge will be understanding thresholds under multiple drivers of change (Sections 6.2.4; 6.4.1).
• Developing a better understanding of the adaptation of the human systems in the coastal zone. At the simplest this could be an inventory of assets at risk, but much more could be done in terms of deepening our understanding of the qualitative trends suggested in Table 6.1 (see also Section 6.4.2) and issues of adaptive capacity.
• Improving impact and vulnerability assessments within an integrated assessment framework that includes natural-human sub-system interactions. This requires a strong inter-disciplinary approach and the targeting of the most vulnerable areas, such as populated megadeltas and deltas, small islands and coastal cities (Section 6.4.3). Improving systems of coastal planning and zoning and institutions that can enforce regulations for clearer coastal governance is required in many countries.
• Developing methods for identification and prioritisation of coastal adaptation options. The effectiveness and efficiency of adaptation interventions need to be considered, including immediate benefits and the longer term goal of sustainable development (Sections 6.6; 6.7).
• Developing and expanding networks to share knowledge and experience on climate change and coastal management among coastal scientists and practitioners.

These issues need to be explored across the range of spatial scales: from local to global scale assessments and, given the long timescales of sea-level rise, implications beyond the 21st century should not be ignored. Thus this research agenda needs to be taken forward across a broad range of activities from the needs of coastal management and adaptation to global integrated assessments and the benefits of mitigation. While some existing global research efforts are pushing in the direction that is recommended, e.g., the IGBP/IHDP LOICZ Science Plan (Kremer et al., 2004), much more effort is required to achieve these goals, especially those referring to the human, integrated assessment and adaptation goals, and at local to regional scales (Few et al., 2004a).