Community Resilience to Climate Change: Theory, Research and Practice

202 being used to forecast changes in the ecosystem or population-level status of conditions in lakes, wetlands, housing markets, and human biomedical assays associated with epileptic seizures. The difficulty is in identifying the right variables to track, according to some authors (Pace, Carpenter, & Cole, 2015). The intention of these newmethods is to allowmanagers and planners to make adjustments in systems before they shift to a less-desirable state, as in a lake that becomes eutrophic or filled with toxic algae, or a tidal wetland that collapses to a mudflat because of repeated storm surge events. One of the most interesting theoretical observations that has come out of these new methods with respect to urban environmental planning is the observation that habitat connectivity may be less desirable in a changing climate (Scheffer et al., 2012). Redundancy may preserve more biodiversity under conditions of stress than connectivity. This research on regime shifts is in early stages as it relates to urban planning, but it is likely to generate a suite of new methods associated with the adaptation framework in planning. Fourth, there is also a need for generative methods that help planners identify appropriate spatial strategies for coastal protection and urban district design. It seems likely that new typologies will be needed that serve to organize the range of possible physical strategies (Hill, 2011, 2015). These can allow planners to assess current conditions and gain new insights about the spatial variability of vulnerability and change. For example, it is likely that logical pairings of urban district types with shoreline types will be needed, such as pairing floodable urban districts with wetland and beach/dune systems, rather than selecting a shoreline strategy independently. Typologies can also help to assess whether suitable strategies are being overlooked, perhaps unintentionally (Hill, 2015). Finally, the use of an “adaptation conceptual framework” in urban environmental planning is prompting new uses of regional process models. Whether planners are using two-dimensional models of change in wetland response or sediment erosion, or more complex models of hydrodynamics and flooding (P. L. Barnard, Jaffe, & Schoellhamer, 2013; Holleman & Stacey, 2014), the change is in how the models are used. In a sustainability framework, the models would be used to optimize spatial configurations. In an adaptation framework, they are more likely to be used iteratively to gain successive approximations of what adaptations are likely to work well or cause problems. For example, the US Geological Survey has developed a hydrodynamic model of the San Francisco Bay that allows planners to estimate tidal flooding depths at different locations around the shoreline (P. Barnard, 2015). Early studies using similar models have shown that in some parts of the San Francisco Bay, building walls on shorelines as an adaptation measure will increase the depth of flooding in nearby areas (Holleman & Stacey, 2014). In only a few years, planners will be able to insert proposals for coastal adaptation into the model and predict whether those adaptation projects will make another property owner’s situation worse. They could use that information to alter the design and re-test it, or to allow or deny a permit. As adaptation changes occur, they will have to be recorded in the physical descriptions within the model so that new predictions would continue to reflect current conditions. 5. CHANGES IN PHILOSOPHICAL ASSUMPTIONS: EPISTEMOLOGY, ONTOLOGY, AND ETHICS IN ENVIRONMENTAL PLANNING One of the key assumptions that underlies urban environmental planning is an epistemological assumption that the processes and patterns of the past can serve as a guide to the future. We have been able to know what is “good” and therefore in need of conservation by comparing our present conditions to the conditions of the past (Steinitz, 2012). The past has been, in a philosophical sense, a source of authority for environmental planning (Spirn, 1984, 2002). We have treated the relatively new practices of industrial agriculture and urbanization as destabilizing forces which must be countered by planning. The goal was to retain and protect elements of an earlier landscape. Our assumption has been that biodiversity, ecosystems, air and water quality, and human health can all be protected most effectively if we retain the framework of a long-standing landscape mosaic (Forman, 1997; Forman & Godron, 1986; Marsh, 1991). In an effort to define and mimic a stable set of fundamental processes within urban regions, urban environmental planners have tended to represent the past as relatively stable. Yet studies from the 1960s demonstrated that American plants and animals experienced dramatic changes in range as a result of the last glaciation of North America, and that they returned individualistically to their current communities—not in the associations we have seen them occupy in over the last hundred years and more (Terasmae, 1970). In spite of that evidence, most environmental planners still tend to think and speak of these plant and animal communities as if they have been stable, and can be maintained as stable units of ecosystems. Given certain temporal scale assumptions, this was reasonable. But given current predictions for rapid climatic change, it is now necessary to let go of this epistemological assumption that the past should be our primary source of authority on how to prioritize the components of present and the future ecosystems (Davis & Shaw, 2001). Presumably, it should be replaced with a heavier reliance on predictive models that represent the dynamics of systems, in spite of their uncertainties. The second philosophical issue raised by global climate change is ontological, or related to how we conceptualize our larger world and its interactions. Scholars and planners have come to recognize that local regions are deeply affected by global trade and financial investment patterns (Harvey, 2000; Sassen, 2014), but nevertheless, professional planners are often put in the position of working as if their jurisdictions are coherent regions with development trajectories independent of global systems. This is an ontological assumption in the sense that policy makers and citizens may think the degree to which we live in a globalized system can be reduced, using new laws, policies and/or physical border walls (Porter, 2016). But in fact, we live in an unprecedented situation of simultaneous environmental and economic changes that continue to occur and produce cascading effects on a global scale. A third philosophical issue involves the ethical assumptions that influence environmental planning. It has been accepted as reasonable