Hawaii's Sea Level Rise Map

The islands of Hawai'i are particularly vulnerable to sea level rise. It is believed that 6,500 structures and 19,800 people in Hawai'i could be exposed to chronic flooding within the next 60 years. The Hawai'i Sea Level Rise Viewer has been released to show which areas of the state will be most affected by rising sea levels.

The map allows users to see which areas could be exposed to coastal hazards from sea level rise, modelling the effect of passive flooding (still water high tide flooding), annual high wave flooding (over wash during the largest wave events of the year), and coastal erosion. The map models sea level rise for four different sea level rise scenarios (these are sea level rises of 0.5 ft, 1.1 ft, 2 ft or 3.2 ft).

The Sea Level Viewer also includes two layers which model the economic loss that could result from rising seas and the possible impact of flooded highways. 38 miles of coastal roads in the state are vulnerable to rising sea level rises. If these become chronically flooded and impassible then access to many communities would become much more difficult. The economic loss layer visualizes the possible cost from land and structures being flooded in the mapped area.

The Hawai'i Sea Level Rise Viewer uses global sea level rise projections from the UN. This model predicts seas could rise by as much as 3.2 feet by the year 2100. More recent models suggest that a rise of 3 feet or more could happen as early as 2060.