Coral Reef Project Active
Explore the fascinating undersea world of coral reefs. Learn how we map, monitor, and model coral reefs so we can better understand, protect, and preserve our Nation's reefs.
Coral reefs are unique ecosystems of plants, animals, and their associated geological framework. Coral reefs cover less than 0.5 percent of the earth's surface, but are home to an estimated 25 percent of all marine species. Second only to tropical rainforests in size and complexity, some scientists estimate that more than one million species of plants and animals are associated with coral reefs. Coral reefs are also of great economic importance to those who live on or visit islands in the Pacific and Atlantic Oceans. Reefs shelter and provide nursery grounds for many commercially and culturally important species of fish and invertebrates, they protect the islands' harbors, beaches, and shorelines from erosion and wave damage by storms, and they are vital to the marine tourism industry. These diverse ecosystems provide valuable goods and services worth about $4 billion each year to the U.S.’s coastal communities. Yet, as important as coral reefs are, these ecosystems are being threatened worldwide.
More than 8,500 square miles (22,000 square kilometers) of coral reef habitat is found in U.S. waters. Most of these coral reefs still appear to be relatively healthy, but some areas of dead and dying coral have been found in recent years. The causes of this degradation are poorly known, but are probably in part related to human activities.
The U.S. Geological Survey (USGS), working closely with academic institutions, state, and other Federal agencies, is spearheading an effort to better understand the geologic and oceanographic controls on the structure and processes of our Nation's coral reef ecosystems.
This web site is a gateway to USGS studies of coral reefs. We focus on the geophysical processes that influence the health and sustainability of coral reefs. From this work we are gaining new insight into the structure of coral reefs, providing the basis for future monitoring, and understanding better both the influences of natural processes and impacts of human activities on coral reef health. These efforts will help to preserve and protect the biodiversity, health, and social and economic value of these remarkable habitats.
Read more coral reef facts.
Learn about our current studies by topic.
Climate Change and Land-use Histories
We are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
We are conducting geophysical and geochemical research to address questions about coastal groundwater-to-reef flow and coral reef health, with the goal of informing management decisions related to planning and implementing activities in priority watershed-coral reef systems.
Reef Hydrodynamics and Sediment Processes
We are developing a better understanding how tides, waves, currents, and both land- and reef-derived sediment influence the development of coral reefs and their adjacent shorelines.
Role of Reefs in Coastal Protection
We are combining ocean, engineering, ecologic, social, and economic modeling to provide a high-resolution, rigorous, spatially-explicit valuation of the coastal flood protection benefits provided by coral reefs and the cost effectiveness of reef restoration for enhancing those benefits.
Reef Resource Assessments - Planning for the Future
We are mapping and assessing all of the important geologic and oceanographic factors to identify those coral reefs most at risk and those reefs that are potentially the most resilient and the most likely to recover from natural and human-driven impacts.
Also, learn about our studies by location:
- Guam
- Hawai‛i
- Kaho‛olawe
- Kaua‛i
- Kwajalein Island
- Lāna‛i
- Maui
- Moloka‛i
- O‛ahu
- Puerto Rico
- Roi-Namur Island
- Tutuila
Please also see the associated Coral Reef Ecosystem Studies (CREST) Project website.
Our partners are numerous and include:
- U.S. Coral Reef Task Force (USCRTF)
- Department of the Interior
- Other Federal Partners
- State Partners
- Territorial and Commonwealth Partners
- Guam Division of Aquatic and Wildlife Resources
- Commonwealth of the Northern Mariana Islands Department of Land and Natural Resources
- American Samoa Department of Marine and Wildlife Resources
- Puerto Rico Department of Natural and Environmental Resources
- U.S. Virgin Islands Department of Planning and Natural Resources
- Academia
- University of California Santa Cruz - Institute of Marine Sciences
- University of Western Australia - Oceans Institute
- University of Puerto Rico at Mayaguez - Center for Applied Ocean Science & Engineering
- University of Hawaiʻi - Hawaiʻi Institute of Marine Biology
- Woods Hole Oceanographic Institution - Department of Geology and Geophysics
- Delft University of Technology - Department of Hydraulic Engineering
- Queen's University - Department of Civil Engineering
- University of Cantabria - Department of Sciences and Techniques in Water and Environment
- Non-governmental Organizations
Below are data releases associated with this project.
Below are multimedia items associated with this project.
Below is a list of our project publications.
HyCReWW: A hybrid coral reef wave and water level metamodel
Stream sediment geochemistry of four small drainages on the north shore of Kauai west of Hanalei
Physical mechanisms influencing localized patterns of temperature variability and coral bleaching within a system of reef atolls
A 50-year Sr/Ca time series from an enclosed, shallow-water Guam coral: In situ monitoring and extraction of a temperature trend, annual cycle, and ENSO and PDO signals
Tropical cyclone projections: Changing climate threats for Pacific Island defense installations
Hydrodynamics of a tidally‐forced coral reef atoll
2018 hurricane and wildfire supplemental funding: USGS recovery activities
The Additional Supplemental Appropriations for Disaster Relief Requirements Act, 2018 (P.L. 115-123), was signed by the President on February 9, 2018. This funding provided $42.2 million to the U.S. Geological Survey (USGS) for equipment repair and replacement, high-resolution elevation data collection in both hurricane- and wildfire-impacted areas, and scientific studies and assessments that will
Geochemical sourcing of runoff from a young volcanic watershed to an impacted coral reef in Pelekane Bay, Hawaii
Meteorologic, oceanographic, and geomorphic controls on circulation and residence time in a coral reef-lined embayment: Faga’alu Bay, American Samoa
Spatial variability of sediment transport processes over intratidal and subtidal timescales within a fringing coral reef system
Mechanisms of wave‐driven water level variability on reef‐fringed coastlines
Most atolls will be uninhabitable by the mid-21st century because of sea-level rise exacerbating wave-driven flooding
Below are news stories associated with this project.
USGS Investigations of coral reefs are cooperative efforts, and our scientists are working in partnership and cooperation with the following organizations.
- Overview
Explore the fascinating undersea world of coral reefs. Learn how we map, monitor, and model coral reefs so we can better understand, protect, and preserve our Nation's reefs.
Coral reefs are unique ecosystems of plants, animals, and their associated geological framework. Coral reefs cover less than 0.5 percent of the earth's surface, but are home to an estimated 25 percent of all marine species. Second only to tropical rainforests in size and complexity, some scientists estimate that more than one million species of plants and animals are associated with coral reefs. Coral reefs are also of great economic importance to those who live on or visit islands in the Pacific and Atlantic Oceans. Reefs shelter and provide nursery grounds for many commercially and culturally important species of fish and invertebrates, they protect the islands' harbors, beaches, and shorelines from erosion and wave damage by storms, and they are vital to the marine tourism industry. These diverse ecosystems provide valuable goods and services worth about $4 billion each year to the U.S.’s coastal communities. Yet, as important as coral reefs are, these ecosystems are being threatened worldwide.
More than 8,500 square miles (22,000 square kilometers) of coral reef habitat is found in U.S. waters. Most of these coral reefs still appear to be relatively healthy, but some areas of dead and dying coral have been found in recent years. The causes of this degradation are poorly known, but are probably in part related to human activities.
The U.S. Geological Survey (USGS), working closely with academic institutions, state, and other Federal agencies, is spearheading an effort to better understand the geologic and oceanographic controls on the structure and processes of our Nation's coral reef ecosystems.
This web site is a gateway to USGS studies of coral reefs. We focus on the geophysical processes that influence the health and sustainability of coral reefs. From this work we are gaining new insight into the structure of coral reefs, providing the basis for future monitoring, and understanding better both the influences of natural processes and impacts of human activities on coral reef health. These efforts will help to preserve and protect the biodiversity, health, and social and economic value of these remarkable habitats.
Read more coral reef facts.
Learn about our current studies by topic.
Climate Change and Land-use Histories
We are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
We are conducting geophysical and geochemical research to address questions about coastal groundwater-to-reef flow and coral reef health, with the goal of informing management decisions related to planning and implementing activities in priority watershed-coral reef systems.
Reef Hydrodynamics and Sediment Processes
We are developing a better understanding how tides, waves, currents, and both land- and reef-derived sediment influence the development of coral reefs and their adjacent shorelines.
Role of Reefs in Coastal Protection
We are combining ocean, engineering, ecologic, social, and economic modeling to provide a high-resolution, rigorous, spatially-explicit valuation of the coastal flood protection benefits provided by coral reefs and the cost effectiveness of reef restoration for enhancing those benefits.
Reef Resource Assessments - Planning for the Future
We are mapping and assessing all of the important geologic and oceanographic factors to identify those coral reefs most at risk and those reefs that are potentially the most resilient and the most likely to recover from natural and human-driven impacts.
Also, learn about our studies by location:
- Guam
- Hawai‛i
- Kaho‛olawe
- Kaua‛i
- Kwajalein Island
- Lāna‛i
- Maui
- Moloka‛i
- O‛ahu
- Puerto Rico
- Roi-Namur Island
- Tutuila
Please also see the associated Coral Reef Ecosystem Studies (CREST) Project website.
Our partners are numerous and include:
- U.S. Coral Reef Task Force (USCRTF)
- Department of the Interior
- Other Federal Partners
- State Partners
- Territorial and Commonwealth Partners
- Guam Division of Aquatic and Wildlife Resources
- Commonwealth of the Northern Mariana Islands Department of Land and Natural Resources
- American Samoa Department of Marine and Wildlife Resources
- Puerto Rico Department of Natural and Environmental Resources
- U.S. Virgin Islands Department of Planning and Natural Resources
- Academia
- University of California Santa Cruz - Institute of Marine Sciences
- University of Western Australia - Oceans Institute
- University of Puerto Rico at Mayaguez - Center for Applied Ocean Science & Engineering
- University of Hawaiʻi - Hawaiʻi Institute of Marine Biology
- Woods Hole Oceanographic Institution - Department of Geology and Geophysics
- Delft University of Technology - Department of Hydraulic Engineering
- Queen's University - Department of Civil Engineering
- University of Cantabria - Department of Sciences and Techniques in Water and Environment
- Non-governmental Organizations
- Science
- Data
Below are data releases associated with this project.
Filter Total Items: 22No Result Found - Multimedia
Below are multimedia items associated with this project.
- Publications
Below is a list of our project publications.
Filter Total Items: 163HyCReWW: A hybrid coral reef wave and water level metamodel
Wave-induced flooding is a major coastal hazard on tropical islands fronted by coral reefs. The variability of shape, size, and physical characteristics of the reefs across the globe make it difficult to obtain a parameterization of wave run-up, which is needed for risk assessments. Therefore, we developed the HyCReWW metamodel to predict wave run-up under a wide range of reef morphometric and offAuthorsAna C. Rueda, Laura Cagigal, Stuart Pearson, Jose Antolínez, Curt D. Storlazzi, Ap van Dongeren, Paula Camus, Fernando J. MendezStream sediment geochemistry of four small drainages on the north shore of Kauai west of Hanalei
Geochemical compositions of fine-grained stream sediment from four drainages on the north shore of the island of Kauai, Hawaii, west of Hanalei and two back-beach sites were explored to increase understanding about land-based runoff and ecological risk from runoff to nearshore coral communities. Stream and beach sediment were collected between July 30 and August 2, 2016, and major, minor, and tracAuthorsRenee K. Takesue, Curt D. StorlazziPhysical mechanisms influencing localized patterns of temperature variability and coral bleaching within a system of reef atolls
Interactions between oceanic and atmospheric processes within coral reefs can significantly alter local-scale (< km) water temperatures, and consequently drive variations in heat stress and bleaching severity. The Scott Reef atoll system was one of many reefs affected by the 2015–2016 mass coral bleaching event across tropical Australia, and specifically experienced sea surface temperature anomaliAuthorsRebecca H. Green, Ryan J. Lowe, Mark L. Buckley, Taryn M. Lopez, James GilmourA 50-year Sr/Ca time series from an enclosed, shallow-water Guam coral: In situ monitoring and extraction of a temperature trend, annual cycle, and ENSO and PDO signals
Located on the northern edge of the West Pacific Warm Pool and having a developed economy and modern infrastructure, Guam is well positioned and equipped for obtaining natural records of the west Pacific maritime paleoclimate. This study was a proof of concept to explore whether useful climate proxy records might be obtained from coral at readily accessible, even if geochemically nonoptimal, coastAuthorsTomoko Bell, Mark Lander, John Jenson, Richard Randall, Judson W. Partin, Nancy G. ProutyTropical cyclone projections: Changing climate threats for Pacific Island defense installations
Potential changing climate threats in the tropical and subtropical North Pacific Ocean were assessed, using coupled ocean-atmosphere and atmosphere-only general circulation models, to explore their response to projected increasing greenhouse gas emissions. Tropical cyclone occurrence, described by their frequency and intensity, near islands housing major U.S. defense installations was the primaryAuthorsMatthew J. Widlansky, Hariharasubramanian Annamalai, Stephen B. Gingerich, Curt D. Storlazzi, John J. Marra, Kevin I. Hodges, Barry Choy, Akio KitohHydrodynamics of a tidally‐forced coral reef atoll
The hydrodynamics of a tidally forced semi‐enclosed coral reef atoll (North Scott) at the edge of the continental shelf of northwestern Australia were investigated by combining field observations and numerical modeling. The observations revealed that the spring tidal range outside the atoll reaches 4 m, and as the water level drops below mean sea level, the reef rim surrounding the shallow (~10–15AuthorsRebecca H. Green, Ryan J. Lowe, Mark L. Buckley2018 hurricane and wildfire supplemental funding: USGS recovery activities
The Additional Supplemental Appropriations for Disaster Relief Requirements Act, 2018 (P.L. 115-123), was signed by the President on February 9, 2018. This funding provided $42.2 million to the U.S. Geological Survey (USGS) for equipment repair and replacement, high-resolution elevation data collection in both hurricane- and wildfire-impacted areas, and scientific studies and assessments that will
AuthorsJo Ellen Hinck, Joseph StachyraByEcosystems Mission Area, Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program, Columbia Environmental Research Center, Pacific Coastal and Marine Science Center, Supplemental Appropriations for Disaster Recovery Activities, Hurricane Harvey, Hurricane Irma, Hurricane Maria, Wildland Fire ScienceGeochemical sourcing of runoff from a young volcanic watershed to an impacted coral reef in Pelekane Bay, Hawaii
Runoff of sediment and other contaminants from developed watersheds threatens coastal ecosystems and services. A sediment geochemical sourcing study was undertaken on a sediment-impacted coral reef flat to identify terrestrial sediment sources and how these changed over time. Geochemical signatures were identified for watershed soils that formed on Hawaiian basaltic and alkalic lavas using relativAuthorsRenee K. Takesue, Curt D. StorlazziMeteorologic, oceanographic, and geomorphic controls on circulation and residence time in a coral reef-lined embayment: Faga’alu Bay, American Samoa
Water circulation over coral reefs can determine the degree to which reef organisms are exposed to the overlying waters, so understanding circulation is necessary to interpret spatial patterns in coral health. Because coral reefs often have high geomorphic complexity, circulation patterns and the duration of exposure, or “local residence time” of a water parcel, can vary substantially over small dAuthorsCurt D. Storlazzi, Olivia M. Cheriton, A. M. Messina, Trent W. BiggsSpatial variability of sediment transport processes over intratidal and subtidal timescales within a fringing coral reef system
Sediment produced on fringing coral reefs that is transported along the bed or in suspension affects ecological reef communities as well as the morphological development of the reef, lagoon, and adjacent shoreline. This study quantified the physical process contribution and relative importance of sea‐swell waves, infragravity waves, and mean currents to the spatial and temporal variability of sediAuthorsAndrew Pomeroy, Ryan J. Lowe, Marco Ghisalberti, Gundula Winter, Curt D. Storlazzi, Michael V. W. CuttlerMechanisms of wave‐driven water level variability on reef‐fringed coastlines
Wave‐driven water level variability (and runup at the shoreline) is a significant cause of coastal flooding induced by storms. Wave runup is challenging to predict, particularly along tropical coral reef‐fringed coastlines due to the steep bathymetric profiles and large bottom roughness generated by reef organisms, which can violate assumptions in conventional models applied to open sandy coastlinAuthorsMark L. Buckley, Ryan J. Lowe, Jeff E. Hansen, Ap R. van Dongeren, Curt D. StorlazziMost atolls will be uninhabitable by the mid-21st century because of sea-level rise exacerbating wave-driven flooding
Sea levels are rising, with the highest rates in the tropics, where thousands of low-lying coral atoll islands are located. Most studies on the resilience of these islands to sea-level rise have projected that they will experience minimal inundation impacts until at least the end of the 21st century. However, these have not taken into account the additional hazard of wave-driven overwash or its imAuthorsCurt D. Storlazzi, Stephen B. Gingerich, Ap van Dongeren, Olivia Cheriton, Peter W. Swarzenski, Ellen Quataert, Clifford I. Voss, Donald W. Field, Hariharasubramanian Annamalai, Greg A. Piniak, Robert T. McCall - Web Tools
- News
Below are news stories associated with this project.
Filter Total Items: 17 - Partners
USGS Investigations of coral reefs are cooperative efforts, and our scientists are working in partnership and cooperation with the following organizations.
Filter Total Items: 22