The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards during storms. The protective services of these natural defenses are not assessed in the same rigorous economic terms as artificial defenses, such as seawalls, and therefore often are not considered in decision-making.
The Impact of Sea-Level Rise and Climate Change on Pacific Ocean Atolls
Providing basic understanding and specific information on storm-wave inundation of atoll islands that house Department of Defense installations, and assessing the resulting impact of sea-level rise and storm-wave inundation on infrastructure and freshwater availability under a variety of sea-level rise and climatic scenarios.
Roi-Namur Island on Kwajalein Atoll serves as our test case
Visit the research overview web site for more information.
The Problem
Many U.S. Pacific islands are atolls fringed with coral reefs and have maximum elevations of 3–5 meters, with mean elevations of 1–2 meters. Sea level in the western Pacific Ocean has been increasing at a rate 2–3 times the global average, resulting in almost 0.3 meters of net rise since 1990. The 2012 US National Climate Assessment provided global sea level rise scenarios that ranged from 0.2 to 2.0 meters by 2100. Regional scenarios are needed. A high surf event in December 2008 overwashed numerous atolls in Micronesia, ruining freshwater supplies and destroying agriculture on approximately 60% of the inhabited islands. Sea-level rise will exacerbate the hazards posed by climate change (storms, waves, temperatures, precipitation, etc.) to infrastructure, freshwater supplies, agriculture, and habitats for threatened and endangered species on U.S. and U.S.-affiliated atoll islands.
Project Objectives
- Provide basic understanding and specific information on storm-wave-induced overwash and inundation of atoll islands that house Department of Defense (DoD) installations.
- Assess the resulting impact of sea-level rise and storm-wave inundation on infrastructure and freshwater availability under a variety of sea-level rise and climatic scenarios.
- Use Roi-Namur Island (Reagan Test Site–U.S. Army Kwajalein Atoll) on Kwajalein Atoll in the Republic of the Marshall Islands (U.S. Associated Pacific Islands) as a test case based on historical information, sea-level rise predictions, and global climate model (GCM) output.
Below are other science projects associated with this project.
Coastal Climate Impacts
Coral Reef Project
Low-lying areas of tropical Pacific islands
Coral Reef Project: Kwajalein Island
Coral Reef Project: Roi-Namur Island
Below are data or web applications associated with this project.
Model parameter input files to compare the influence of channels in fringing coral reefs on alongshore variations in wave-driven runup along the shoreline
Model parameter input files to compare locations of coral reef restoration on different reef profiles to reduce coastal flooding
Cross-reef wave and water level data from coral reef environments (ver. 3.0, January 2024)
Database to model three-dimensional flow over coral reef spur-and-groove morphology
Coral reef profiles for wave-runup prediction
Model parameter input files to compare wave-averaged versus wave-resolving XBeach coastal flooding models for coral reef-lined coasts
Physics-based numerical model simulations of wave propagation over and around theoretical atoll and island morphologies for sea-level rise scenarios
Below are multimedia items associated with this project.
The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards during storms. The protective services of these natural defenses are not assessed in the same rigorous economic terms as artificial defenses, such as seawalls, and therefore often are not considered in decision-making.
Below are publications associated with this project.
A numerical study of geomorphic and oceanographic controls on wave-driven runup on fringing reefs with shore-normal channels
Spectral wave-driven bedload transport across a coral reef flat/lagoon complex
Modeling three-dimensional flow over spur-and-groove morphology
The impacts of a changing climate to DOD coastal facilities in the tropical Pacific Ocean
Sea‐level rise will drive divergent sediment transport patterns on fore reefs and reef flats, potentially causing erosion on atoll islands
The importance of explicitly modelling sea-swell waves for runup on reef-lined coasts
In situ observations of wave transformation and infragravity bore development across reef flats of varying geomorphology
Hydro-morphological characterization of coral reefs for wave runup prediction
Steps to develop early warning systems and future scenarios of wave-driven flooding along coral reef-lined coasts
Assessing morphologic controls on atoll island alongshore sediment transport gradients due to future sea-level rise
HyCReWW: A hybrid coral reef wave and water level metamodel
Physical mechanisms influencing localized patterns of temperature variability and coral bleaching within a system of reef atolls
Below are news stories associated with this project.
Providing basic understanding and specific information on storm-wave inundation of atoll islands that house Department of Defense installations, and assessing the resulting impact of sea-level rise and storm-wave inundation on infrastructure and freshwater availability under a variety of sea-level rise and climatic scenarios.
Roi-Namur Island on Kwajalein Atoll serves as our test case
Visit the research overview web site for more information.
The Problem
Many U.S. Pacific islands are atolls fringed with coral reefs and have maximum elevations of 3–5 meters, with mean elevations of 1–2 meters. Sea level in the western Pacific Ocean has been increasing at a rate 2–3 times the global average, resulting in almost 0.3 meters of net rise since 1990. The 2012 US National Climate Assessment provided global sea level rise scenarios that ranged from 0.2 to 2.0 meters by 2100. Regional scenarios are needed. A high surf event in December 2008 overwashed numerous atolls in Micronesia, ruining freshwater supplies and destroying agriculture on approximately 60% of the inhabited islands. Sea-level rise will exacerbate the hazards posed by climate change (storms, waves, temperatures, precipitation, etc.) to infrastructure, freshwater supplies, agriculture, and habitats for threatened and endangered species on U.S. and U.S.-affiliated atoll islands.
Project Objectives
- Provide basic understanding and specific information on storm-wave-induced overwash and inundation of atoll islands that house Department of Defense (DoD) installations.
- Assess the resulting impact of sea-level rise and storm-wave inundation on infrastructure and freshwater availability under a variety of sea-level rise and climatic scenarios.
- Use Roi-Namur Island (Reagan Test Site–U.S. Army Kwajalein Atoll) on Kwajalein Atoll in the Republic of the Marshall Islands (U.S. Associated Pacific Islands) as a test case based on historical information, sea-level rise predictions, and global climate model (GCM) output.
Below are other science projects associated with this project.
Coastal Climate Impacts
Coral Reef Project
Low-lying areas of tropical Pacific islands
Coral Reef Project: Kwajalein Island
Coral Reef Project: Roi-Namur Island
Below are data or web applications associated with this project.
Model parameter input files to compare the influence of channels in fringing coral reefs on alongshore variations in wave-driven runup along the shoreline
Model parameter input files to compare locations of coral reef restoration on different reef profiles to reduce coastal flooding
Cross-reef wave and water level data from coral reef environments (ver. 3.0, January 2024)
Database to model three-dimensional flow over coral reef spur-and-groove morphology
Coral reef profiles for wave-runup prediction
Model parameter input files to compare wave-averaged versus wave-resolving XBeach coastal flooding models for coral reef-lined coasts
Physics-based numerical model simulations of wave propagation over and around theoretical atoll and island morphologies for sea-level rise scenarios
Below are multimedia items associated with this project.
The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards during storms. The protective services of these natural defenses are not assessed in the same rigorous economic terms as artificial defenses, such as seawalls, and therefore often are not considered in decision-making.
The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards during storms. The protective services of these natural defenses are not assessed in the same rigorous economic terms as artificial defenses, such as seawalls, and therefore often are not considered in decision-making.
Below are publications associated with this project.
A numerical study of geomorphic and oceanographic controls on wave-driven runup on fringing reefs with shore-normal channels
Spectral wave-driven bedload transport across a coral reef flat/lagoon complex
Modeling three-dimensional flow over spur-and-groove morphology
The impacts of a changing climate to DOD coastal facilities in the tropical Pacific Ocean
Sea‐level rise will drive divergent sediment transport patterns on fore reefs and reef flats, potentially causing erosion on atoll islands
The importance of explicitly modelling sea-swell waves for runup on reef-lined coasts
In situ observations of wave transformation and infragravity bore development across reef flats of varying geomorphology
Hydro-morphological characterization of coral reefs for wave runup prediction
Steps to develop early warning systems and future scenarios of wave-driven flooding along coral reef-lined coasts
Assessing morphologic controls on atoll island alongshore sediment transport gradients due to future sea-level rise
HyCReWW: A hybrid coral reef wave and water level metamodel
Physical mechanisms influencing localized patterns of temperature variability and coral bleaching within a system of reef atolls
Below are news stories associated with this project.