Characterizing inundation risk for Majuro Atoll

Narrow strips and circles of land rise barely above sea level.
The atolls of the Marshall Islands are some of the most at-risk areas in the world as sea level continues to rise. (Photo: Storlazzi/USGS)

With an average elevation of just seven feet above sea level, the Republic of the Marshall Islands is acutely vulnerable to inundation from both episodic events such as storm surge and chronic conditions such as sea-level rise. Some projections estimate that future sea-level rise could exceed the average elevation of these islands by 2100. Already, residents are facing extreme high tides and 16 foot swells that flood the islands with saltwater, damaging homes and infrastructure and contaminating the freshwater supply.

Land elevation is the primary factor that determines the vulnerability of coastal areas to inundation. This project builds on previous work in which a 1-meter resolution digital elevation model (DEM) was developed for Majuro Atoll, home to the capital and largest city in the Marshall Islands. Researchers will use this DEM to map areas of Majuro Atoll that are vulnerable to inundation, based on different water level scenarios. For example, these maps can be used to answer the question of which areas would flood should seas rise by 0.4, 0.8, or 1 meter, and will represent the first detailed assessment of sea-level rise vulnerability for Majuro.

The results of this project will support assessments of how future inundation events could impact ecosystems, infrastructure, the freshwater supply, and agroforestry on Majuro Atoll. This much-needed information will provide government authorities and local community groups with an improved understanding of the types of actions needed to prepare for future inundation and an estimated timeline for when these actions would best be implemented.





Dean Gesch
Research Scientist, USGS Earth Resources Observation and Science (EROS) Center


Jeff Danielson
Physical Geographer, USGS Earth Resources Observation and Science (EROS) Center