Annual high tides, such as this one at Waikiki Beach in 2009, will become more frequent as sea level rises. Credit: Chris Conger, UH Sea Grant College Program

Flooding in the Mapunapuna area of Honolulu due to heavy rains and high tides. The storm drain system, located below sea level, was retrofitted with one-way drains and the flooding was largely mitigated. Credit: D. Oda

Seasonal high surf at Laniakea, O’ahu results in annual road closures. Credit: Dolan Eversole, NOAA Sea Grant Coastal Storms Program Coordinator, Pacific Region

Regional armoring due to long-term chronic erosion has resulted in the loss of sandy beach in Lanikai, O‘ahu. Credit: UH Sea Grant

Digital representation of the windward coastal plain near Kualoa, O‘ahu. Areas in red are currently 1 meter (3.3 feet) above mean high tide. Low areas may be among the first to experience drainage problems as sea level rises. Credit: Mr. Matthew Barbee & Dr. Charles Fletcher, UH Coastal Geology Group

Access to Honolulu International Airport runways would be compromised with a 3-foot rise in sea level. Credit: Mr. Matthew Barbee & Dr. Charles Fletcher, UH Coastal Geology Group

A 3-foot rise in sea level also would impact stormwater drainage in the high-density Ala Moana commercial area. Credit: Mr. Matthew Barbee & Dr. Charles Fletcher, UH Coastal Geology Group

The FEMA flood zone in some areas on the north shore of Kaua‘i requires structures to be build at a minimum elevation. Decision-makers could require or incentivize similar measures to adapt to sea-level rise through accommodation. Credit: Dennis Hwang

There are limited relocation options along sections of the Kamehameha Highway, O‘ahu that are threatened by sea-level rise. Emergency armoring currently protects the road. Similarly, decision-makers could use sea walls to adapt to sea-level rise through protection in areas where retreating from the coastline is not possible. Credit: Dolan Eversole, NOAA Sea Grant Coastal Storms Program Coordinator, Pacific Region

Coastal construction setback from the shoreline provides an open beach area for public use at Kahala Beach, O‘ahu. Decision-makers could use setbacks to adapt to sea-level rise through retreat. Credit: Dolan Eversole, NOAA Sea Grant Coastal Storms Program Coordinator, Pacific Region