Alaska Sea Level Rise

Assessing the Vulnerability of Alaska's Coastal Habitats to Accelerating Sea-level Rise Using the SLAMM Model: A Case Study for Cook Inlet serves as National Wildlife Federation's final report required under its cooperative funding agreement (701818J719) with the U.S. Fish and Wildlife Service (USFWS) Region 7 Coastal Program. This report increases our understanding of the vulnerability of Alaska's coastal systems to climate change and can help inform future coastal restoration, protection, and adaptation measures.

The report appendices include a detailed account of the application of the Sea Level Affecting Marshes Model (SLAMM) in the Cook Inlet area. Also included is a white paper that provides an overview of Alaska data gaps and challenges to applying SLAMM in Alaska and suggestions for preliminary steps that should be taken to apply SLAMM with maximum effectiveness across the state.

• Assessing the Vulnerability of Alaska's Coastal Habitats to Accelerating Sea-level Rise Using the SLAMM Model: A Case Study for Cook Inlet (PDF)
• Appendix A: A White Paper on Date Requirements and Date Inventory for Alaska SLAMM Analyses (PDF)
• Appendix B: SLAMM Analysis of Kenai Peninsula and Anchorage, AK, Final Report (PDF)

Alaska is blessed with an amazing diversity of coastal habitats, from rocky cliffs and sandy beaches to tidal flats, marshes, and eelgrass beds. These habitats support hundreds of fish and wildlife species, including a majority of Alaska's threatened and endangered animals, and they are a linchpin for the state's economy, culture, and quality of life. Understanding the relative vulnerability of species, habitats, and/or ecosystems to the impacts of climate change is a necessary step in the development of meaningful strategies to reduce those risks. Collecting good local data and modeling at a local level is an essential part of developing this understanding.

Over the past two years, National Wildlife Federation has worked with Warren Pinnacle Consulting, Inc, to investigate the potential impact of sea-level rise on coastal habitats in areas of Cook Inlet, Alaska. We used the SLAMM model, which simulates the dominant processes involved in wetland conversions and shoreline changes during long-term sea-level rise. While the SLAMM model has been successfully applied in a number of coastal areas across the U.S., this is the first time it has been used to study Alaska’s coastal habitats. As a result, we considered this study a pilot project, and the results of the study are more significant for the lessons learned than for the specific impacts projected for the case study locations.

Ultimately, this study underscores the fact that Alaska poses unique challenges for sea-level rise modeling. The primary challenges are related to significant data gaps, especially the lack of high quality elevation data across the majority of the state, as well as the coarse quality of some other data inputs.