U.S. Natural Resources and Climate Change: Concepts and Approaches for Management Adaptation

In addition to understanding which organisms and systems are most sensitive to climate change, managers need to know the baseline conditions of a given system. Ecologists, especially marine ecologists, have drawn attention to the fact that the world has changed so much that it can be hard to determine an accurate historical baseline for any system (Pauly 1995; Jackson and others 2001). An understanding of a system’s long history can be essential because the historical record may include information about past responses to extreme stresses and perturbations. When dealing with sensitive, endangered, or stressed systems, experimental perturbation is not feasible. When available, paleoecological records can be used to examine past ranges of natural environmental variability and past organismal responses to climate change (Willis and Birks 2006). Although in an experimental sense “uncontrolled,” there is no lack of both historic and recent examples of perturbations and recoveries through which to examine resilience.

Historic baselines have the potential to offer insights into how to manage for climate change. For example, while the authority to acquire land interests and water rights exists under the Wild and Scenic Rivers Act, lack of baseline data on flow regimes makes it difficult to determine how, when, and where to use this authority (Palmer and others 2008). Data on species composition and distribution; rates of freshwater discharge into estuaries; river flooding regimes; magnitude and timing of anadromous fish runs; forest fire regimes; and home ranges, migration patterns, and reproductive dynamics of sensitive organisms would all be useful for making management decisions given the potential effects of climate change (Joyce and others 2008; Scott and others 2008; Peterson and others 2008; Palmer and others 2008).

However, baselines also have the potential to be misleading. For example, Joyce and others (2008) noted that historic baselines are useful only if climate is incorporated into those past baselines and the relationship of vegetation to climate is explored. An ecological baseline based on an historic climate that will never again be seen in a region should not be used as a goal. At the same time, adjusting baselines to accommodate changing conditions requires caution to avoid unnecessarily compromising ecosystem integrity for the future and losing valuable historical knowledge.

Although monitoring is already recognized as an important component of management, in the face of climate change, monitoring will be even more essential. Monitoring will be needed to detect changes in baseline conditions as well as to facilitate timely adaptation actions. Monitoring also provides a means to gauge the effectiveness of management actions. Some monitoring may be designed to detect general ecological trends in poorly understood systems. However, most monitoring programs should be designed with specific hypotheses in mind and with trigger points that will initiate a policy or management re-evaluation (Gregory and others 2006). For instance, using a combination of baseline and historical data, a monitoring program could be set up with pre-defined thresholds for a species’ abundance or growth rate, or a river’s flow rate, which, once exceeded, would prompt a re-examination of management objectives.

Monitoring targets will have to be carefully selected to represent the system in a tractable way and to give clear information about possible management options (Gregory and Failing 2002). Some systems will require site-specific monitoring, whereas others will be able to take advantage of more general monitoring programs (see Kareiva and others 2008 for examples of potential monitoring targets). For instance, Joyce and others (2008) highlight the need to monitor both native plant species and non-native species while suggesting a more general monitoring program would be adequate to detect changes in tree establishment, growth and mortality. One example of such a general program is the National Phenology Network’s monitoring of the timing of ecological events across the country (Joyce and others 2008).

Although directed, intensive monitoring programs may seem daunting, there are several opportunities to build on existing and developing efforts. Opportunities include the National Science Foundation’s National Ecological Observation Network and the Park Service’s Vital Signs program (e.g., Mau-Crimmins and others 2005). Some federal lands have detailed species inventories (e.g., the national parks are developing extensive species inventories for the Natural Resource Challenge; Baron and others 2008) or detailed stream flow measurements. However, while monitoring is critical, it is only one step in the management process and does not itself address the effects of climate change.

Even when equipped with climate projections, baseline information and monitoring data, managers still face very complex decisions. The high degree of uncertainty inherent in assessments of climate change impacts can make it difficult for a manager to translate results from those assessments into practical management actions (Dessai and others 2009). However, uncertainty is not the same as ignorance or lack of information—it simply means that there is more than one outcome possible as a result of climate change. Fortunately, there are approaches for dealing with uncertainty that allow progress. One key step is scenario-building (Hannah and others 2002; Johnson and Weaver 2009).

While it is not possible to predict the changes that will occur, managers can get an indication of the expected range of changes using scenarios, and they can use that range to develop appropriate responses. Rather than focusing on a single “most likely” outcome, planning for the range will provide responses that are more robust to climate change (Johnson and Weaver 2009). To develop a set of scenarios—i.e., internally consistent views of reasonably plausible futures in which decisions may be explored (adapted from Porter 1985; IPCC 1994; Schwartz 1996)—quantitative or qualitative visions of the future are developed. These scenarios explore current assumptions and expand viewpoints of the future. In the climate change impacts area, approaches for developing scenarios may range from model-based scenarios, to analog scenarios, to informal synthetic scenarios.

Model-based scenarios explore plausible future conditions through direct representations of complex patterns of change. Scenarios are developed using a number of different realizations from global climate models that are driven by multiple alternative future emissions paths. The outputs are spatially downscaled using statistical methods or regional climate models, and the resulting scenarios become the basis for exploring potential ecosystem responses. Analog scenarios make use of existing climate information, either at the region in question (temporal analogs) or from another region that currently experiences a climate anticipated to resemble the future climate of the site under study (spatial analogs). Temporal analogs may be constructed from paleoclimate information or from the historical instrumental record. Synthetic scenarios specify changes in particular variables and apply those changes to an observed time series. For example, a historic time series of annual mean precipitation for the northeastern United States would be increased by 2% to create a synthetic scenario, but no other characteristics of precipitation would change. A synthetic scenario might start by simply stating that in the future, summers will be hotter and drier. That scenario would be used to alter the sets of historic time series, and decision makers would explore how management might respond (IPCC-TGICA 2007).

Along with developing multiple scenarios using the methods described above to discover potential ecosystem changes, it may also be useful to conduct sensitivity analyses that further explore ecosystem behaviors and identify ranges of potential changes in ecosystem endpoints. In such analyses, key attributes of an ecosystem are examined to see how they respond to systematic changes in selected climate drivers (IPCC-TGICA 2007; Johnson and Weaver 2009). For example, precipitation and temperature would be perturbed at specific increments over a plausible range of changes—e.g., 1% changes in precipitation over a range of −5% to +10% from the historic baseline, and 1°C changes in temperature over a range of +1° to +4°C from the historic baseline—as inputs to an ecosystem model to determine how ecosystem processes and endpoints would respond. This approach may help managers to identify thresholds beyond which key management goals become unattainable.

Scenario-building approaches and sensitivity analyses provide the foundation for scenario planning—planning for multiple possible future events (Peterson and others 2003; Carpenter and others 2006; Cumming 2007). If sensitivity analyses are performed, those results can be used to select the most relevant scenarios that both address managers’ needs and represent the widest possible, but still plausible, futures. The strategy is to then design a variety of management strategies that are robust across the whole range of scenarios and associated impacts. For detailed guidance on using scenario data for climate impact assessments, see IPCC-TGICA (2007).

Ecological studies combined with managers’ expertise reveal several categories of approaches for managing natural systems for resilience in the face of disturbance. Insights from experiences with unpredictable and extreme events such as hurricanes, floods, pest and disease outbreaks, invasions, and forest fires can be readily applied to managing in the context of climate change. A clear exposition of these approaches is the starting point for developing best practices aimed at climate adaptation. The seven approaches discussed below—(1) reduce anthropogenic stresses, (2) protect key ecosystem features, (3) maintain representation, (4) replicate, (5) restore, (6) identify refugia, and (7) relocate organisms—involve techniques that enhance a system’s resilience to climatic changes. All of these adaptation approaches ultimately contribute to resilience, whether at the scale of individual protected area units, or at the scale of regional/national systems. The seven categories are inclusive of the range of adaptation options found across the six management systems reviewed in the CCSP (2008) report. It is important to note that the strategies discussed under these approaches are options, not recommendations; the efficacy of many of the individual strategies has yet to be fully tested and would depend on the specifics of place, ecosystem, project design, etc.

Once adaptation strategies have been selected, adaptive management is likely to be an effective method for implementation, given uncertainty in their effectiveness. Adaptive management is an iterative process in which management actions are followed by targeted monitoring, the results of which inform changes in management actions (Walters and Hilborn 1978). In this cyclic process, management actions serve as full-scale field experiments. Since adaptive management emphasizes managing based on observation and continuous learning, it provides a means for addressing varying degrees of uncertainty in our knowledge of current and future climate change impacts (Holling 1978; Walters 1986; FEMAT 1993; Moir and Block 2001; Stankey and others 2003). Adaptive management in the context of climate change involves the consideration of potential climate impacts, the design of management actions that take those impacts into account, monitoring of climate-sensitive species and processes to measure management effectiveness, and the redesign and implementation of improved (or new) management actions. Examples include flood release experiments in the Grand Canyon (Baron and others 2008) and at the Glen Canyon dam (National Research Council 1999). Releasing water from a dam allows for the application of highly regulated experimental treatments and assessments of effects.

Recent examinations of the difficulty of implementing adaptive management have emphasized that the temporal and spatial scale, dimensions of uncertainty, risks, and insufficient institutional support can create major difficulties with applying adaptive management. When one considers adaptive management in response to climate change, every one of these potential difficulties is at play (Arvai and others 2006; Gregory and others 2006). The critical challenge will be to state explicit scientific hypotheses; establish monitoring programs with predefined triggers that initiate a re-examination of management approaches; and create flexible policies and institutional frameworks (Gregory and others 2006). These challenges do not mean adaptive management is impossible—only that attention to hypotheses, monitoring, periodic re-evaluations, and flexibility are necessary.

Federal land and water managers can use existing legislative tools opportunistically by applying traditional features or levers in non-traditional ways (see Table 8). For example, legislative features can be used to coordinate management outside of jurisdictional boundaries. Generally, the United States Fish and Wildlife Service has ample proprietary authority to engage in transplantation/relocation, habitat engineering (including irrigation-hydrologic management), and captive breeding to support conservation (Scott and others 2008). These activities are especially applicable to managing shifts in species distributions and preventing species extirpations likely to result from climate change. Portions of existing legislation could also be used to influence dam operations at the state level as a means of providing adaptive flow controls under future climate changes (e.g., using the Clean Water Act to prevent low flows in vulnerable stream reaches, adjusting thermal properties of flows). As these examples suggest, climate change impacts often can be addressed within existing legislative frameworks.

Each management system mandates the development of a management plan. Developing climate change adaptation strategies should be part of all planning exercises, both at the level of individual units and collaboratively with other management units. This might encourage more units in the same broad geographical area to look for opportunities to coordinate on the development of regional management plans (see Table 9). A natural next step then would be to prioritize actions within the management plan. Different approaches may be used at different scales to decide on management activities across the public lands network or at specific sites. Such planning has already occurred in the National Forest System, where the Olympic, Mt. Baker, and Gifford Pinchot National Forests have combined resources to produce coordinated plans (Joyce and others 2008). The Olympic National Forest’s exemplary strategic planning process also enables climate change considerations to be incorporated via its specific guidance on prioritization.

In some cases, existing management plans may already set the stage for climate adaptation. A good example is the Forest Service’s adoption of an early detection/rapid response strategy for invasive species (Joyce and others 2008). This same thinking could be translated to an early detection/rapid response management approach to climate impacts. Even destructive extreme climate events can become management opportunities for addressing long-standing problems such as overbuilding in floodplains or degradation of coastal wetlands; in some estuaries it may be possible for decision makers to use up-front planning to prevent rebuilding in hazardous areas of high flood risk and to restore wetlands with provisions for their upland migration with sea level rise (Peterson and others 2008).

Management plans that are allowed to incorporate climate change adaptation strategies but that have not yet done so provide a blank canvas of opportunity. State wildlife action plans (Scott and others 2008) and ecosystem-based fishery management plans (Peterson and others 2008) are examples of this type of leveraging opportunity. Stakeholder processes can be an opportunity to move forward with new management approaches if public education campaigns on adaptation to climate change precede the stakeholder involvement. The issue of climate change has received sufficient attention that many people in the public have begun to demand actions by the agencies to address it.

Level of funding and staff capacity may pose significant barriers to adaptation to climate change (see Table 10). Managers may lack sufficient resources to deal with routine needs and even fewer resources to address unexpected events that will likely increase as a result of climate change. Further, while climate change stands to increase the scope of management by increasing both the area of land requiring active management and the planning burden per unit area (because of adaptive management techniques), some agencies also face decreasing personnel in some regions (Scott and others 2008). In addition, many agency personnel do not have adequate training, expertise, or understanding to effectively address emerging issues. Yet despite these constraints, there may be creative ways to augment the workforce and stretch budgets to alter or supplement practices that would enable adaptation to climate change.

Tackling the challenge of managing natural resources in the face of climate change requires that staff members not only feel valued but also empowered by their institutions. Many federal land management employees began their careers as passionate stewards of the nation’s natural resources. With the threat of climate change further compounding management challenges, it is important that this passion be fully cultivated. Existing employees could be effectively trained (or specialist positions designated) to attack climate change issues within the context of their current job descriptions and management frameworks (Joyce and others 2008). For example, the National Park Service has recently implemented a program to educate park staff on climate change issues, in addition to offering training for presenting this information to park visitors in 11 national parks (Baron and others 2008). Such activities offer a cost-effective mechanism for empowering existing employees with both knowledge and public outreach skills.

Agency employees play important roles as crafters and ultimate implementers of management plans and strategies. Risk aversion coupled with the uncertainty surrounding climate change could lead managers to opt for the no-action approach, when the impending severe effects of climate change should elicit the opposite response (e.g., Hall and Fagre 2003). Human resource policies that are supportive of employees who take risks and acknowledge that risks sometimes lead to mistakes will be critical for managers making difficult choices under climate change (see Table 10). A “safe-to-fail” policy––in which the system can recover without irreversible damage to either natural or human resources (e.g., careers and livelihoods)––would be exemplary of this approach (Baron and others 2008).

Effective collaboration and linkages among managers and resource scientists offer a variety of opportunities (see Table 11). First, resource scientists have monitoring data and research results that are often underused. Second, monitoring efforts could be conducted with specific objectives in mind to increase usefulness for managers. Finally, scientists can support management by targeting their research. All of these are opportunities for interactions among scientists and managers that provide information relevant to major management challenges. The need for monitoring efforts may provide impetus for a more unified approach across agencies or management regions, which would serve to not only provide more comprehensive information but also to minimize costs associated with monitoring efforts.

While it is laudable to seek more and better information, it is equally important for the resource management community to proceed with designing strategies that are robust in the face of limited information. Due to uncertainties in modeling and in the response of ecosystems to climate change and to management interventions, precise information on some questions may be impossible (or prohibitively expensive or time consuming) to acquire. If this is the case and if the information is needed for a specific adaptation action, then it may be that the action is not practical or is at a high risk for failure with implementation.

Another need on the information and science front is investment in resources and training for the promotion of flexible approaches to adaptation management. This would include developing general guidance on the likely impacts of concern and their implications for ecosystem services and management. It could also mean investing in “climate science translators” who could work in partnership with managers and planners to translate the projections of climate models, understand likely impacts, and help design adaptation responses. These individuals would also function as outreach staff who could explain to the public what climate change might mean to long-standing recreational opportunities or management goals.

Many federal lands and waters provide excellent opportunities for educating the public about climate change. National parks and wildlife refuges already put extensive resources into education and outreach for environmental, ecological, and cultural subjects (Baron and others 2008; Scott and others 2008), and these efforts could be augmented to inform the public about climate change. Traditional communication venues such as information kiosks and signs, documentaries, and brochures could demonstrate the effects of various climate-change scenarios on specific places or systems, making use of photos or video documenting coral bleaching and retreating glaciers, or presenting modeling results of projected changes in specific lands or waters (Kerr 2004, 2005).

Experiences gained from natural resource management programs and other activities offer insights into the application of ecosystem based management under changing climatic conditions. Ecosystem based management takes into account interactions among ecosystem components and management sectors to optimize the benefits of activities aimed at maintaining ecosystem services under a multitude of existing stressors (Peterson and Estes 2001; Peterson and others 2008; Levin and others 2009). One lesson learned from this approach is that it may be necessary to expand the management scale beyond the boundaries of a single habitat type, conservation area, or political or administrative unit to encompass an entire ecosystem or region. Currently, management plans for forests, national parks, wildlife refuges, rivers, estuaries, and marine protected areas are often developed for discrete geographies with specific attributes (species, ecosystems, commodities), without recognition that they may be nested within other systems (Kareiva and others 2008). For example, marine protected areas are often within national estuaries, and wild and scenic rivers are often within national parks. Plans are seldom developed to fully consider the matrix in which they are embedded and the extent to which those attributes may vary over time in response to drivers external to the management system. Climate change adaptation opportunities may be missed if land and water resources are thought of as distinct, static, or out of context of a regional and even continental arena. A better approach would be to systematically broaden and integrate management plans as much as possible. Although a single national park or national forest may have limited capacity for adaptation, the entire system of parks and forests and refuges in a region may have powerful capacities. When spatial scales of consideration are larger, federal agencies often have mutually reinforcing goals that may result in the enhancement of their ability to manage cooperatively across landscapes (Leeworthy and Wiley 2003).

The scale of the challenge posed by climate disruption and the uncertainty surrounding future changes demand coordinated, collaborative responses that go far beyond traditional “agency-by-agency” responses to stressors and threats. A recurring theme across CCSP (2008) is the need for a structured, interagency effort and for collaboration in everything from research to management and land acquisition. Scientists and managers across agencies and management systems would benefit from greater sharing of data, models, and experiences. It may be necessary to develop formal structures and policies that foster extensive interagency cooperation.

One interagency program established specifically to address climate change research is the U.S. Climate Change Science Program (CCSP). The goals of this program are to develop scientific knowledge of the climate system, causes of changes in the system, and the effects of such changes on ecosystems, society, and the economy—all in order to determine how best to apply that knowledge to decision-making. Climate change research conducted across 13 U.S. government departments and agencies is coordinated through the CCSP. The CCSP could be expanded to include management research and coordination to bridge the gap between resource management needs and scientific research priorities. This would enhance the goal of the CCSP to apply existing knowledge to decision-making.

While the CCSP may be the most relevant example of interagency collaboration for climate change, other programs such as the National Invasive Species Council, the Joint Fire Science Program, and National Interagency Fire Center could also serve as models. The analogy for climate change adaptation would be a group that would coordinate management activities, interpret research findings, inform on priority-setting, and disseminate data and tools. One option would be to designate climate experts to advise agency scientists at both national and site levels with guidance, translation of climate impact projections, and coordination across agencies (Kareiva and others 2008). Regardless of the exact collaborative structure, any interagency effort would benefit from the coordination of regional and national monitoring databases that can access and readily provide comprehensive information. This would increase the capacity to make informed decisions related to climate-induced changes, and the pooling of resources would allow for more effective data generation and sharing. Ideally, this would be a web-based clearinghouse with maps, a literature database, and pertinent models that could be easily downloaded and updated frequently as new information becomes available.

Climate change not only requires consideration of how to adapt management approaches; it also requires reconsideration of management objectives. In a world with unlimited resources and staff time, climate adaptation would simply be a matter of management innovation, monitoring, and more scientific research. In reality, priorities may need to be re-examined and re-established to focus adaptation efforts appropriately and make the best use of limited resources (CCSP 2008; Kareiva and others 2008). At the regional scale, one example of the type of change that may be needed is in selected estuaries where freshwater flow patterns are expected to change and salt water is expected to penetrate further upstream. Given this scenario, combined with the goal of protecting anadromous fishes, models could be used to project shifts in critical propagation habitats, and management efforts could be refocused to those sites (Peterson and others 2008).

In the example above, the goal is still attainable with some modifications. However, in general, resource managers could face significant constraints on their authority to re-prioritize and make decisions about which goals to modify and how to accomplish those modifications (Joyce and others 2008). National-level policies and priorities may have to be re-examined with thought toward how to accommodate and enable such changes in management at the regional level.

Because climate-driven changes in some ecological systems are likely to be extreme, priority-setting eventually may have to involve triage (Metzger and others 2005; Millar and others 2007). Some goals may have to be abandoned and new goals established if climate change effects are severe enough. Even with substantial management efforts, some systems may not be able to maintain the ecological properties and services that they provide in today’s climate. For other systems or species, the cost of adaptation may far outweigh the ecological, social, or economic returns it would provide. In such cases, resources may be better invested elsewhere. One simple example of triage would be the decision to abandon habitat management efforts for a population of an endangered species on land at the “trailing” edge of its shifting range (Scott and others 2008). If the refuge that currently provides habitat for the species will be unsuitable within the next 50 years, it might be best to actively manage for habitat elsewhere and, depending on the species and the circumstances, investigate the potential for relocation. Such decisions will have to be made with extreme care (Scott and others 2008). In addition to evaluating projected trends in climate and habitat suitability, it will be necessary to monitor the species or habitats in question to determine whether the projected trends are being realized. All of the changes in management discussed in the next section would likely require fundamental changes in policy and engagement in triage at the national level.

Agencies have established best practices based on many years of past experience. Unfortunately, dramatic climate change will change the rules of the game, rendering some of yesterday’s best practices tomorrow’s bad practices. Experienced managers now realize that they can anticipate changes in conditions, especially conditions that might alter the impacts of grazing, fire, logging, harvesting, recreation, sand so forth. Such anticipatory thinking will be critical, as climate change will likely exceed ecosystem thresholds over time such that strategies to increase ecosystem resilience will no longer be effective (Millar and others 2007). At this point, major shifts in ecosystem processes, structures, and components will be unavoidable, triggering a need to “manage for change”.

Managing for change means actively managing an ecosystem through a transformation to a new state (see Walker and others 2004). This could involve, for example, using species properly suited to the expected future climate when revegetation and silviculture are used for post-disturbance rehabilitation; genotypes and species (including “new” species) that are better adjusted to projected changes in mean temperature, rainfall, variability and extremes could be used. In Tahoe National Forest, managing for change may mean that white fir would be favored over red fir, pines would be preferentially harvested at high elevations over fir, and species would be shifted upslope within expanded seed transfer guides (Joyce and others 2008). As another example, given climate change, some restoration may cease to be an appropriate undertaking. In a situation where warming waters render selected river reaches no longer suitable for salmon, restoration of those reaches may not be a realistic management activity (Joyce and others 2008). The same applies to meadows, where restoration efforts may need to be abandoned due to probable succession to non-meadow conditions. Additional examples of adaptation options for managing for change, drawn from across the management systems reviewed in CCSP (2008), are presented in Table 12.

The task of managing for change may be difficult because trajectories of ecosystem alterations under climate change may be highly uncertain. This renders management goals less clear. Under these circumstances, scenario-based planning provides a key to moving forward. Development of realistic scenario-based plans may require a philosophical shift concerning when species or systems can be preserved, when restoration is an appropriate post-disturbance response, etc. For example, as illustrated poignantly in estuaries, it is impractical to attempt to keep ecosystem boundaries static. After a flood, there is often intense pressure to restore to the pre-flooding state (Peterson and others 2008). To ensure sound management responses, guidelines for the scenarios under which restoration and rebuilding should occur (or be abandoned) could be established in advance of disturbances. In this sense, disturbances could become opportunities for managing toward a distribution of human population and infrastructure that is more realistic given a changing climate.

Managing for change may also be difficult from a societal perspective as well as an ecological perspective. The public appreciates iconic ecosystems and expects that their protected status means that they will be maintained in their current state. A common perception has been that the mandate of management agencies is to maintain public lands and waters unchanged, and the public may not recognize the potential impossibility of this goal. Since management will not be able to prevent change, it will be important to manage the public’s expectations as part of “managing for change”.