Abstract

Sea level rise is an inevitable outcome of global warming that will continue through many centuries even if human-generated global greenhouse gas (GHG) emissions were stopped today. However, much of what happens with future sea level rise will depend on our ability, or inability, to implement aggressive global carbon emissions reduction programs envisioned through the 2016 Paris Climate Accord.

This Sea Level Rise Vulnerability and Adaptation Report (Report), initially mandated by Act 83 in 2014 (Hawaii Climate Change Adaptation Initiative) and expanded by Act 32 in 2017 (Hawaiʻi Climate Change Mitigation and Adaptation Initiative), provides the first state-wide assessment of Hawaii’s vulnerability to sea level rise and recommendations to reduce our exposure and sensitivity to sea level rise and increase our capacity to adapt. This Report combines the best available science on climate change and sea level rise from sources such as the Intergovernmental Panel on Climate Change (IPCC) Assessment Report 5 (IPCC 2014), more recent scientific reports from the National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (NASA), as well as the best-available peer reviewed scientific research articles. The Report also provides recommendations based on emerging good practices and framed through extensive stakeholder consultations. The Report is considered a “living” output that will be updated as new information becomes available. The update process will be guided by learning questions crafted around the assumptions and limitations that need to be revisited over time as climate science evolves and new challenges appear on the horizon. While the Report focuses on sea level rise vulnerabilities and adaptation, it should also strengthen our State’s resolve to do our part in reducing GHG emissions in line with Act 32 and the Paris Climate Accord. In addition, this report is intended to serve as a framework for identifying and managing other climate change threats facing Hawai‘i.