A growing body of knowledge shows that human-induced climate change is occurring and its societal impacts are projected to expand (Skinner 2012). It is also well understood that the environmental consequences of climate change will interact with existing social stresses within communities and influence the level of realized societal impact. This report analyzed socioeconomic, demographic, and infrastructure data to quantify the social sensitivity of reserves and all U.S. coastal communities to climate change at both reserve and coastal county levels. Therefore climate sensitivity, in the context of this report, is defined as whether and how a reserve or group of reserves will be affected by a change in climate conditions, measured over the particular environmental or social geography.
KEY FINDINGS
The reserve social sensitivity analysis revealed some large-scale spatial patterns in sensitivity around the nation, which characterized regional differences. Reserves on the East Coast of the U.S. were generally found to have lower social sensitivity to climate change than those in the Gulf of Mexico or on the West Coast. This does not mean that East Coast reserves are not susceptible to climate change impacts, only that the communities associated with East Coast reserves are better situated from a socio-economic perspective to respond to climate change impacts. The patterns in reserve social sensitivity around the country are related to differences in each reserve community’s cultural barriers, dependence on natural resources, labor characteristics, and income levels. More specifically, reserves with higher socio-demographic sensitivity often exhibited one of more of the following characteristics:
- Greater employment within natural resource-dependent extractive industries
- Lower per capita income levels and median home values
- Higher percentage of Hispanic and/or American Indian residents
- Higher percentage of the population less than high school educated
The coastal county-level social sensitivity analysis included counties in which at least 15 percent of a county’s total land area was located within the nation’s coastal watershed or 15 percent of a county was within a coastal sub-basin. This analysis revealed spatial heterogeneity in social sensitivity; meaning that
counties with low, moderate, and high sensitivity are commonly found located near each other. The following patterns emerged following a cluster analysis of the coastal county sensitivity data:
- The northern portions of the East and West coasts of the contiguous U.S., as well as the Great Lakes region, are primarily characterized by relatively low to moderate social sensitivity.
- The southern portion of the East Coast, as well as the Gulf Coast (with the exception of portions of Florida), has a mixture of low and high social sensitivities, diversely distributed.
- Portions of Florida, Texas, California, and Alaska have areas of very high social sensitivity; interestingly, those areas are also often next to low sensitivity areas.
- Alaska has a number of coastal areas with extremely high social sensitivity.
Overall, the results indicate that the scale of analysis for social sensitivity (e.g., reserve versus coastal county) is important, which is to be expected given the relative nature of the analysis and the differences in analytical units. While the data provide a basis for understanding large-scale trends at both the reserve and coastal county scales, it can also provide a richer understanding of the factors influencing sensitivity at a given location. Any further interpretation of the data should be done with consideration of the nature of the data used in the analysis, the relative nature of the index, and the scale of analysis.
References
Skinner, L. (2012). A long view on climate sensitivity. Science, 337, 917-919.