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

6.6 Adaptation: practices, options and constraints

This section first highlights issues that arise with interventions designed to reduce risks to natural and human coastal systems as a consequence of climate change. As recognised in earlier IPCC assessments (Bijlsma et al., 1996; McLean et al., 2001), a key conclusion is that reactive and standalone efforts to reduce climate-related risks to coastal systems are less effective than responses which are part of integrated coastal zone management (ICZM), including long-term national and community planning (see also Kay and Adler, 2005). Within this context, subsequent sections describe the tools relevant to adaptation in coastal areas, options for adaptation of coastal systems, and current and planned adaptation initiatives. Examples of the costs of, and limits to, coastal adaptation are described, as are the trade-offs. Constraints on, limitations to, and strategies for strengthening adaptive capacity are also described. Finally, the links between coastal adaptation and efforts to mitigate climate change are discussed.

6.6.1 Adaptation to changes in climate and sea level Issues and challenges

Recent extreme events (Box 6.5), whether climate-related or not, have highlighted many of the challenges inherent in adapting to changes in climate and sea level. One constraint on successful management of climate-related risks to coastal systems is the limited ability to characterise in appropriate detail how these systems, and their constituent parts, will respond to climate change drivers and to adaptation initiatives (Sections 6.2.4 and 6.4; Finkl, 2002). Of particular importance is understanding the extent to which natural coastal systems can adapt and therefore continue to provide essential life-supporting services to society. The lack of understanding of the coastal system, including the highly interactive nature and non-linear behaviour (Sections 6.2 and 6.4), means that failure to take an integrated approach to characterising climate-related risks increases the likelihood that the effectiveness of adaptation will be reduced, and perhaps even negated. Despite the growing emphasis on beach nourishment (Hanson et al., 2002), the long-term effectiveness and feasibility of such adaptive measures remains uncertain, especially with the multiple goals explicit within ICZM (Section The question of who pays and who benefits from adaptation is another issue of concern. Public acceptance of the need for adaptation, and of specific measures, also needs to be increased (Neumann et al., 2000). The significant and diverse challenges are summarised in Table 6.9 and discussed further in the identified sections.

Table 6.9. Major impediments to the success of adaptation in the coastal zone.

Impediment Example Reference Section 
Lack of dynamic predictions of landform migration Pethick, 2001 
Insufficient or inappropriate shoreline protection measures Finkl, 2002 
Data exchange and integration hampered by divergent information management systems  Hale et al., 2003 
Lack of definition of key indicators and thresholds relevant to coastal managers Rice, 2003 
Inadequate knowledge of coastal conditions and appropriate management measures Kay and Adler, 2005 
Lack of long-term data for key coastal descriptors  Hall, 2002 
Fragmented and ineffective institutional arrangements, and weak governance Moser, 2000 
Societal resistance to change Tompkins et al., 2005a 6.6.3 

Box 6.5. Recent extreme events – lessons for coastal adaptation to climate change

Recent extreme events, both climate and non-climate related, that had major consequences for coastal systems, provide important messages for adaptation to climate change. Scientific literature and government reports emanating from hurricane and cyclone impacts (e.g., Cook Islands (Ingram, 2005); Katrina (US Government, 2006); Australia (Williams et al., 2007), flood impacts (e.g., Mumbai (Wisner, 2006)) and the Boxing Day Sumatran tsunami (UNEP, 2005; UNOCHA, 2005) include the following.

  • An effective early warning communication and response system can reduce death and destruction;
  • Hazard awareness education and personal hazard experience are important contributors to reducing community vulnerability;
  • Many factors reduce the ability or willingness of people to flee an impending disaster, including the warning time, access and egress routes, and their perceived need to protect property, pets and possessions;
  • Coastal landforms (coral reefs, barrier islands) and wetland ecosystems (mangroves, marshes) provide a natural first line of protection from storm surges and flooding, despite divergent views about the extent to which they reduce destruction;
  • Recurrent events reduce the resilience of natural and artificial defences;
  • In the aftermath of extreme events, additional trauma occurs in terms of dispossession and mental health;
  • Uncoordinated and poorly regulated construction has accentuated vulnerability;
  • Effective disaster prevention and response rely on strong governance and institutions, as well as adequate public preparedness.