Climate-driven migration: prioritizing cultural resources threatened by secondary impacts of climate change

Archaeological sites are increasingly threatened by primary impacts of climate change, including sea-level rise, flooding, and erosion. These important sites represent cultural heritage and contain unique past environmental, ecological, and climate information. Stewardship of these cultural resources is generally limited to mitigation and salvage of immediately threatened sites, with little forethought given to secondary impacts of climate change. Secondary impacts are defined in this paper as climate-driven resettlement and associated development and may result in destruction of archaeological sites via resettlement of affected populations. The United Nations predicts increases above existing rates of resettlement of climate-affected communities from areas in which in situ infrastructure adaptations are not economically feasible, legal, or physically possible. Resulting development will likely disturb archaeological sites in interior regions. These cultural, environmental, and climate archives may be lost if urgent, unplanned climate-driven resettlement overwhelms state and local protections. Thus, planning for climate-driven resettlement should include standard methods for assessing threats to archaeological sites. Using Southern Maine as a pilot study, we report a trial methodology for identifying towns likely to experience rapid increases in population and infrastructure development related to climate-driven resettlement. Socioeconomic and demographic data, land cover change analyses, and archaeological records are combined in this risk assessment framework. The products are town-level maps that identify archaeological sites threatened by secondary impacts of climate change (climate-driven migration). This tool enables prioritization of threatened sites prior to potential destruction by large-scale migration and associated economic development and makes timely development compliance with federal and state legislation more likely.