National Park Service managers face unprecedented challenges as climate change affects park resources and visitor experience. Within the context of a preservation mandate, park management practices embrace a wide array of options for maintaining and restoring healthy functioning ecosystems. Coastal environments are particularly challenged as sea level rise and storms threaten coastal parks and seashore. These systems are naturally dynamic and current management practices are designed to take these changing conditions into account. For example, Assateague Island National Seashore in Maryland and Virginia has undertaken a sand bypassing program to provide sediment to support island migration even as construction and dredging nearby aim to keep the coastline constant. Storms in this region can cause island breeching and overwash and while these processes provide habitat for threatened species such as piping plover and seabeach amaranth, coastal erosion at Assateague Island may soon exceed the island's threshold for maintaining its existing configuration. Two adjacent seashores in North Carolina, Cape Hatteras and Cape Lookout, are a microcosm of a "human altered" and more "natural" series of barrier islands. At Cape Hatteras, there are constructed dune features and unincorporated villages within the boundaries of the seashore, while at the same time the park is the location of the best publicized example of managed retreat in the US. In 1999, the Cape Hatteras Lighthouse was moved inland 2,870, allowing the shoreline to continue to evolve. Climate change compounds the challenge of maintaining naturally functioning coastal environments and raises difficult questions about when management intervention is no longer feasible or even desirable.
Management of cultural and natural resources in coastal national parks in an era of climate change will require a thorough re-examination of NPS Management Policies. Current policies direct managers to mitigate human caused alteration of park resources but these were not written within the context of widespread anthropogenic change that protected areas are now experiencing. Although evidence for climate change is unequivocal, in many cases the timing and magnitude of events and their effects on complex ecosystems cannot be precisely predicted. Scenario Planning is being developed as a structured framework for decision making across a range of plausible futures. In this way managers are beginning to identify actions and decision points that can be monitored and re-evaluated as new information is acquired.