Leveraging modern climatology to increase adaptive capacity across protected areas

Human-driven changes in the global environment pose an increasingly urgent challenge for the management of ecosystems that is made all the more difficult by the uncertain future of both environmental conditions and ecological responses. Land managers need strategies to increase regional adaptive capacity, but relevant and rapid assessment approaches are lacking. To address this need, we developed a method to assess regional protected area networks across biophysically important climatic gradients often linked to biodiversity and ecosystem function. We plot the land of the southwestern United States across axes of historical climate space, and identify landscapes that may serve as strategic additions to current protected area portfolios. Considering climate space is straightforward, and it can be applied using a variety of relevant climate parameters across differing levels of land protection status. The resulting maps identify lands that are climatically distinct from existing protected areas, and may be utilized in combination with other ecological and socio-economic information essential to collaborative landscape-scale decision-making. Alongside other strategies intended to protect species of special concern, natural resources, and other ecosystem services, the methods presented herein provide another important hedging strategy intended to increase the adaptive capacity of protected area networks.

Fig. 2. The Index of Missing Assets, or IMA, the mean distance from unprotected (S3 and S4) lands (colored) to the 1,000 closest protected (S1 or S2) lands (black), in seasonal climate space, is based on normalized climatic constraints of summer and winter seasons. The color scheme is a combination of the seasonal IMA scores where a low summer IMA contributes yellow, a low winter IMA score contributes blue, and high scores contribute red, to the resulting map. The IMA highlights both seasonal and spatial patterns of climatic differences between protected and unprotected areas. Patterns of potential missing assets are partially driven by the broad gradient of climate across the study extent, suggesting missing assets at the edges of the region. (a) Regional-scale assessments indicate variation in climate along the edges of the study extent, for example in western NV. Seasonal differences can also be seen, e.g., southern New Mexico’s unique summer climate and the Wasatch Mountains’ distinct winter climate (both circled in frame a), as compared to the region’s protected areas, respectively. (b) Ecoregional-scale assessments result in more heterogeneity and relatively greater IMA values. Shared borders between the Colorado Plateau and Arizona/New Mexico Mountain provinces are surrounded by landscapes that have differing climate from protected areas in those ecoregions. Lands such as those around Hellsgate Wilderness Area (circled in c and d), are potential missing assets at both spatial scales.

Fig. 3. Land management of S3 and S4 “matrix lands” is highly varied across the Southwestern U.S.’s (a) climate space (10% random sample of data points shown for legibility). (b) An overlay of land ownership and land use onto the regional IMA (not all ownership categories are shown) provides an example of the complexity of land use decisions that could be informed with the climate space approach. As an example, some of the lands identified as the most climatically distinct from the region’s protected area network span patchworks of State Trust, tribal, USDA-Forest Service and private ownership.

Davison, J. E., L. J. Graumlich, E. L. Rowland, G. T. Pederson, and D. D. Breshears. 2012. Leveraging modern climatology to increase adaptive capacity across protected area networks. Global Environmental Change, 22, 268-274.