This section considers planned, mainly (but not exclusively) anticipatory adaptations, undertaken or directly influenced by governments or collectives as a public policy initiative. These adaptations represent conscious policy options or response strategies to concerns about climate change (Benioff et al., 1996; Fankhauser, 1996; Smith, 1997; Pielke, 1998; UNEP, 1998). Public adaptation initiatives may be direct or indirect, such as when they encourage or facilitate private actions (Leary, 1999). Planned adaptation by public agencies represents an alternative or complementary response strategy to mitigation (of net GHG emissions). Analyses of such planned adaptations are essentially normative exercises involving identification of possible policy strategies and evaluation of the relative merit of alternatives, as an aid to policy development.

Numerous reasons have been given for pursuing planned adaptations at this time (see Table 18-4). Public adaptation initiatives are regarded not as a substitute for reducing GHG emissions but as a necessary strategy to manage the impacts of climate change (Burton, 1996; Pielke, 1998). Adaptation can yield benefits regardless of the uncertainty and nature of climate change (Ali, 1999). Fankhauser et al. (1998) and Leary (1999) outline rationales for public adaptation policies or projects relative to relying on private actions. Leary concludes that "we cannot rely solely or heavily on autonomous adjustments of private agents to protect public goods and should examine public policy responses to do so." Planned anticipatory adaptation, as recognized in the UNFCCC (Article 3.3), is aimed at reducing a system's vulnerability by diminishing risk or improving adaptive capacity.

Table 18-4: Six reasons to adapt to climate change now (Burton, 1996).
1)	Climate change cannot be totally avoided.
2)	Anticipatory and precautionary adaptation is more effective and less costly than forced, last-minute, emergency adaptation or retrofitting.
3)	Climate change may be more rapid and more pronounced than current estimates suggest. Unexpected events are possible.
4)	Immediate benefits can be gained from better adaptation to climate variability and extreme atmospheric events.
5)	Immediate benefits also can be gained by removing maladaptive policies and practices.
6)	Climate change brings opportunities as well as threats. Future benefits can result from climate change.

There has been work on the process by which public agencies might or should undertake planned adaptation strategies, particularly noting the steps to be followed, relationships with other policy and management objectives, and the criteria with which options might be evaluated (Louisse and Van der Meulen, 1991; Carter et al., 1994; Smith and Lenhart, 1996; Stakhiv, 1996; Major and Frederick, 1997; Smith, 1997). Klein and Tol (1997) identify five generic objectives of adaptation:

1. Increasing robustness of infrastructural designs and long-term investments—for example, by extending the range of temperature or precipitation a system can withstand without failure and changing the tolerance of loss or failure (e.g., by increasing economic reserves or by insurance)
2. Increasing the flexibility of vulnerable managed systems—for example, by allowing mid-term adjustments (including change of activities or location) and reducing economic lifetimes (including increasing depreciation)
3. Enhancing the adaptability of vulnerable natural systems—for example, by reducing other (nonclimatic) stresses and removing barriers to migration (including establishing eco-corridors)
4. Reversing trends that increase vulnerability (also termed "maladaptation")—for example, by introducing setbacks for development in vulnerable areas such as floodplains and coastal zones
5. Improving societal awareness and preparedness—for example, by informing the public of the risks and possible consequences of climate change and setting up early-warning systems.

Research addressing future adaptations to climate change tends to be normative, suggesting anticipatory adaptive strategies to be implemented through public policy. Generally, such adaptation recommendations are based on forecasts of expected (though still largely unpredictable) climate change. Recommended adaptations:

• Tend to be in response to changes in long-term mean climate, though more specific elements of climate change (e.g., sea-level change) gain focus when sector-specific adaptations are proposed (e.g., integrated coastal zone management) (Al-Farouq and Huq, 1996; Smith et al., 1996), and some studies specifically examine potential adaptations to variability and extreme events (e.g., Appendi and Liverman, 1996; Yang, 1996; Yim, 1996).
• Range in scope from very broad strategies for adaptation (e.g., enhancing decisionmakers' awareness of climatic change and variability) to recommendations of sector-specific policy. Sectors receiving particular attention include water resources, coastal resources, agriculture, and forest resources (Smith and Lenhart, 1996; Smith et al., 1996; Hartig et al., 1997; Mendelsohn and Bennett, 1997).
• Tend to be regionally focused (Smith and Lenhart, 1996), in recognition of the fact that vulnerability to the impacts of climate change is highly spatially variable. There is interest in developing countries and nations with economies in transition, given their greater reliance on natural systems-based economic activity (such as agriculture) (e.g., Magalhães, 1996; Smith et al., 1996; Kelly and Adger, 1999).

Because no single set of adaptive policy recommendations can be universally appropriate, several studies suggest means by which proposed adaptations may be selected and evaluated. At a very basic level, the success of potential adaptations is seen to depend on the flexibility or effectiveness of the measures, such as their ability to meet stated objectives given a range of future climate scenarios (through either robustness or resilience), and their potential to produce benefits that outweigh costs (financial, physical, human, or otherwise) (Smith and Lenhart, 1996). Clearly, these are difficult criteria to assess, given the complexity of adaptation measures, the variable sensitivities and capacities of regions, and uncertainties associated with climate change and variability. Some research (e.g., Carter, 1996; Smith and Lenhart, 1996; Smith et al., 1996; de Loë and Kreutzwiser, 2000) offers supplementary characteristics of, or criteria for, the identification of adaptations:

• The measure generates benefits to the economy, environment, or society under current conditions (i.e., independent of climate change).
• The measure addresses high-priority adaptation issues such as irreversible or catastrophic impacts of climate change (e.g., species extinction), long-term planning for adaptation (e.g., infrastructure), and unfavorable trends (e.g., deforestation, which may inhibit future adaptive flexibility).
• The measure targets current areas of opportunity (e.g., land purchases, revision of national environmental action or development plans, research and development).
• The measure is feasible—that is, its adoption is not significantly constrained by institutional, social/cultural, financial, or technological barriers.
• The measure is consistent with, or even complementary to, adaptation or mitigation efforts in other sectors.
  

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