The overall vulnerability of species and ecosystems to climate change is dependent on three factors: climate exposure, sensitivity, and adaptive capacity. The degree of climate exposure of an area is measured by metrics such as the velocity of climate change (how quickly one would need to move to track changes in climate in any one given place; see appendix for details of methods), which are based directly on climatic data. Sensitivity of biodiversity to projected exposure is evaluated by means of models that predict species’ habitat under current and future climate. Adaptive capacity is the ability of a region’s biodiversity to persist and adapt in place despite changes in climate including increases in climatic variability. The ultimate goal of the planning process is to enhance adaptive capacity at landscape and regional scales.
The field of climate-adaptation planning is in an early stage of development. Many disparate mapping methods are being applied without a clear ecological or policy context. The field of conservation planning was in a similar state in the early 1990s before the work of Noss, Pressey, Groves and others synthesized disparate approaches into a coherent planning framework. A few recent efforts, such as the Yale Framework (Schmitz et al. in prep.), have begun to organize existing knowledge on climate adaptation planning. The research proposed here builds on these recent efforts by providing a comprehensive comparison and synthesis of the many approaches that have previously been developed, along with detailed application of those methods to the majority of western North America.
The broad scope of previous efforts such as the Yale Framework necessarily limits the level of methodological detail in their publications. As a result, they primarily provide a menu that lists potential methods, rather than a cookbook that describes how these methods can be best integrated in planning. In order to build on this previous work, we will develop 1) a comparison of mapped priority areas suggested by different methods and 2) examples of integration among multiple methods for contrasting landscapes. This project differs from previous studies in that it seeks to 1) compare a full spectrum of alternative methods over many contrasting regions, and 2) refine understanding of the conceptual relationship between the various methods and their practical relationship in the planning process.
Our approach builds on Reed Noss’s three-track approach to conservation planning (Noss and Cooperrider 1994) which integrates consideration of coarse-filter conservation targets (vegetation communities or physical habitat types), fine-filter targets (such as the locations of localized endemic species), and habitat for wide-ranging focal species. We adopt this three-track approach but modify it to the climate-adaptation context by dividing coarse-filter targets into those based on climatic data (such velocity of climate change) and those based on physical habitat types (land facets; see appendix for details). We incorporate both types of species-based goals identified by Noss: fine-filter species data and focal species habitat.
Based on this framework, the wide variety of climate adaptation planning approaches can be grouped into four categories: climate-based coarse-filter, physical-habitat-based coarse-filter, fine-filter species models, and focal species models. Within each of these approaches, past studies have focused on three aspects of adaptive capacity: identifying and protecting refugia where conditions change least or conversely, an area in a given landscape where many species may be able to persist, corridors which allow species to track changes, and finally representation based on the premise that “saving all the
parts” enhances adaptive capacity.
The various methods evaluated in this study address all of the six objectives identified by the Yale Framework: a) protect current patterns of biodiversity, b) forecast future patterns of biodiversity, c) maintain ecological processes, d) maintain and restore ecological connectivity, e) protect climate refugia, and f) protect the “ecological stage" (physical habitat types).