Coastal Climate Impacts Active
The impacts of climate change and sea-level rise around the Pacific and Arctic Oceans can vary tremendously. Thus far the vast majority of national and international impact assessments and models of coastal climate change have focused on low-relief coastlines that are not near seismically active zones. Furthermore, the degree to which extreme waves and wind will add further stress to coastal systems has also been largely disregarded. By working to refine this area of research, USGS aims to help coastal managers and inhabitants understand how their coasts will change.
Why research on climate change and sea-level rise is important
Climate change and sea-level rise are already impacting coastal communities in many locations worldwide, including the U.S. west coast, Alaska, Hawaiʻi, and U.S. affiliated Pacific islands.
In the western tropical Pacific, elevated rates of sea-level rise (up to 1 centimeter/year) affect coastal infrastructure, freshwater resources, and terrestrial and marine ecosystems on U.S.-affiliated islands like the Marshall Islands, American Samoa, and the Northern Marianas. Alterations in storm patterns, contamination of freshwater aquifers by saltwater flooding, and permanent inundation by rising sea level—all fueled by climate change—threaten long-term human habitation on many of these atolls. Efforts to relocate coastal inhabitants from some low-lying Pacific Islands are already underway.
Along Arctic shores of Alaska, shoreline erosion and habitat loss are accelerating due to increasing permafrost thaw and sea ice forming much later in the year, leaving the coast more susceptible to waves and storm surge. Alaskan government agencies and land-use planners are relocating some Native Alaskan villages and critical airstrips farther inland from eroding shores, such as Kivalina on the northwestern coast.
The U.S. west coast is vulnerable as well. In California alone, roughly half a million people and $100 billion worth of coastal property are at risk during the next century. In highly developed coastal areas such as San Francisco Bay and Puget Sound, hundreds of millions of dollars are being spent on restoration of nearshore ecosystems, which protect shorelines from erosion by waves and provide habitat for socially and economically important species. But resource managers remain uncertain whether outcomes of these efforts will be resilient to projected sea-level rise.
Because the impacts of climate change and sea-level rise around the Pacific and Arctic vary considerably, no single solution can mitigate the impacts. Coastal communities, along with federal, state, and local managers, need better scientific information and tools to plan for the particular threats they may face from saltwater flooding, shoreline erosion, and habitat loss.
Historically, simple “bathtub” models of future sea levels have assumed a static coast—one that is neither subsiding nor rising, neither retreating nor growing seaward—and they calculate future flooding based on just sea-level rise and tides, ignoring the impacts of storms. Those models cannot adequately account for the diverse influences that affect most coasts, including sediment input, how the coast is shaped, and “forcings”—atmospheric and oceanographic conditions that force the environment to change (for example, wind and circulation patterns, wave heights and directions).
Thus, in tectonically active coastlines like the U.S. west coast, USGS seeks to develop models that incorporate sea-level rise projections combined with storm impacts, as well as potential changes in wave heights and storm patterns associated with climate change.
What the USGS is doing
We are developing rigorous research tools to understand the physical impacts that climate change and sea-level rise will have on dynamic geologic settings along Pacific and Arctic coasts. This research covers an enormous range of coastal settings: from permafrost coasts, to the Puget Sound estuary, the California coast, and low-lying Pacific atolls.
By understanding the effects of extreme storms, including coastal flooding, changes in the shoreline, and movement of sediment, we can develop better models for understanding long-term vulnerability of sea-level rise in various coastal settings, and help coastal managers and businesses plan for a changing climate.
Our areas of study include the following, with brief descriptions of each.
Climate impacts to Arctic coasts
The Arctic region is warming faster than anywhere else in the nation. Understanding the rates and causes of coastal change in Alaska is needed to identify and mitigate hazards that might affect people and animals that call Alaska home.
Low-lying areas of tropical Pacific islands
Sea level is rising faster than projected in the western Pacific, so understanding how wave-driven coastal flooding will affect inhabited, low-lying islands—most notably, the familiar ring-shaped atolls—as well as the low-elevation areas of high islands in the Pacific Ocean, is critical for decision-makers in protecting infrastructure or relocating resources and people.
Dynamic coastlines along the western U.S.
The west coast of the United States is extremely complex and changeable because of tectonic activity, mountain building, and land subsidence. These active environments pose a major challenge for accurately assessing climate change impacts, since models were historically developed for more passive sandy coasts.
Estuaries and large river deltas in the Pacific Northwest
Essential habitat for wild salmon and other wildlife borders river deltas and estuaries in the Pacific Northwest. These estuaries also support industry, agriculture, and a large human population that’s expected to double by the year 2060, but each could suffer from more severe river floods, higher sea level, and storm surges caused by climate change.
Climate impacts on Monterey Bay area beaches
For a beach town like Santa Cruz, preserving beaches by mitigating coastal erosion is vital. USGS scientists conduct regular surveys of the beaches in the Monterey Bay region to better understand the short- and long-term impacts of climate change, El Niño years, and sea-level rise on a populated and vulnerable coastline.
Collaborators
Collaborators include USGS Coastal and Marine Geology Program colleagues in Woods Hole, Massachusetts, and St. Petersburg, Florida, and researchers with the USGS Western Ecological Research Center on Mare Island, California. Academic collaborators include those from University of Hawaiʻi, Oregon State University, University of Alaska, University of California, Scripps Institution of Oceanography, and University of Cantabria (Spain). Also involved are colleagues and federal partners from such agencies as the U.S. National Park Service, U.S. Fish and Wildlife Service, U.S. Department of Defense, and National Oceanic and Atmospheric Administration.
Below are all of the research topics associated with this project.
Below are data releases associated with this project.
Below are multimedia items associated with this project.
Below are publications associated with this project.
Towards determining spatial methane distribution on Arctic permafrost bluffs with an unmanned aerial system
Physical mechanisms influencing localized patterns of temperature variability and coral bleaching within a system of reef atolls
Hydrodynamics of a tidally‐forced coral reef atoll
Geochemical sourcing of runoff from a young volcanic watershed to an impacted coral reef in Pelekane Bay, Hawaii
Assessing and communicating the impacts of climate change on the Southern California coast
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
Most atolls will be uninhabitable by the mid-21st century because of sea-level rise exacerbating wave-driven flooding
Mechanisms of wave‐driven water level variability on reef‐fringed coastlines
Nonhydrostatic and surfbeat model predictions of extreme wave run-up in fringing reef environments
Vulnerability of coral reefs to bioerosion from land-based sources of pollution
A Bayesian-based system to assess wave-driven flooding hazards on coral reef-lined coasts
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- Overview
The impacts of climate change and sea-level rise around the Pacific and Arctic Oceans can vary tremendously. Thus far the vast majority of national and international impact assessments and models of coastal climate change have focused on low-relief coastlines that are not near seismically active zones. Furthermore, the degree to which extreme waves and wind will add further stress to coastal systems has also been largely disregarded. By working to refine this area of research, USGS aims to help coastal managers and inhabitants understand how their coasts will change.
Why research on climate change and sea-level rise is important
Climate change and sea-level rise are already impacting coastal communities in many locations worldwide, including the U.S. west coast, Alaska, Hawaiʻi, and U.S. affiliated Pacific islands.
In the western tropical Pacific, elevated rates of sea-level rise (up to 1 centimeter/year) affect coastal infrastructure, freshwater resources, and terrestrial and marine ecosystems on U.S.-affiliated islands like the Marshall Islands, American Samoa, and the Northern Marianas. Alterations in storm patterns, contamination of freshwater aquifers by saltwater flooding, and permanent inundation by rising sea level—all fueled by climate change—threaten long-term human habitation on many of these atolls. Efforts to relocate coastal inhabitants from some low-lying Pacific Islands are already underway.
Along Arctic shores of Alaska, shoreline erosion and habitat loss are accelerating due to increasing permafrost thaw and sea ice forming much later in the year, leaving the coast more susceptible to waves and storm surge. Alaskan government agencies and land-use planners are relocating some Native Alaskan villages and critical airstrips farther inland from eroding shores, such as Kivalina on the northwestern coast.
The U.S. west coast is vulnerable as well. In California alone, roughly half a million people and $100 billion worth of coastal property are at risk during the next century. In highly developed coastal areas such as San Francisco Bay and Puget Sound, hundreds of millions of dollars are being spent on restoration of nearshore ecosystems, which protect shorelines from erosion by waves and provide habitat for socially and economically important species. But resource managers remain uncertain whether outcomes of these efforts will be resilient to projected sea-level rise.
Because the impacts of climate change and sea-level rise around the Pacific and Arctic vary considerably, no single solution can mitigate the impacts. Coastal communities, along with federal, state, and local managers, need better scientific information and tools to plan for the particular threats they may face from saltwater flooding, shoreline erosion, and habitat loss.
Historically, simple “bathtub” models of future sea levels have assumed a static coast—one that is neither subsiding nor rising, neither retreating nor growing seaward—and they calculate future flooding based on just sea-level rise and tides, ignoring the impacts of storms. Those models cannot adequately account for the diverse influences that affect most coasts, including sediment input, how the coast is shaped, and “forcings”—atmospheric and oceanographic conditions that force the environment to change (for example, wind and circulation patterns, wave heights and directions).
Thus, in tectonically active coastlines like the U.S. west coast, USGS seeks to develop models that incorporate sea-level rise projections combined with storm impacts, as well as potential changes in wave heights and storm patterns associated with climate change.
What the USGS is doing
We are developing rigorous research tools to understand the physical impacts that climate change and sea-level rise will have on dynamic geologic settings along Pacific and Arctic coasts. This research covers an enormous range of coastal settings: from permafrost coasts, to the Puget Sound estuary, the California coast, and low-lying Pacific atolls.
By understanding the effects of extreme storms, including coastal flooding, changes in the shoreline, and movement of sediment, we can develop better models for understanding long-term vulnerability of sea-level rise in various coastal settings, and help coastal managers and businesses plan for a changing climate.
Our areas of study include the following, with brief descriptions of each.
Climate impacts to Arctic coasts
The Arctic region is warming faster than anywhere else in the nation. Understanding the rates and causes of coastal change in Alaska is needed to identify and mitigate hazards that might affect people and animals that call Alaska home.Low-lying areas of tropical Pacific islands
Sea level is rising faster than projected in the western Pacific, so understanding how wave-driven coastal flooding will affect inhabited, low-lying islands—most notably, the familiar ring-shaped atolls—as well as the low-elevation areas of high islands in the Pacific Ocean, is critical for decision-makers in protecting infrastructure or relocating resources and people.Dynamic coastlines along the western U.S.
The west coast of the United States is extremely complex and changeable because of tectonic activity, mountain building, and land subsidence. These active environments pose a major challenge for accurately assessing climate change impacts, since models were historically developed for more passive sandy coasts.Estuaries and large river deltas in the Pacific Northwest
Essential habitat for wild salmon and other wildlife borders river deltas and estuaries in the Pacific Northwest. These estuaries also support industry, agriculture, and a large human population that’s expected to double by the year 2060, but each could suffer from more severe river floods, higher sea level, and storm surges caused by climate change.Climate impacts on Monterey Bay area beaches
For a beach town like Santa Cruz, preserving beaches by mitigating coastal erosion is vital. USGS scientists conduct regular surveys of the beaches in the Monterey Bay region to better understand the short- and long-term impacts of climate change, El Niño years, and sea-level rise on a populated and vulnerable coastline.Collaborators
Collaborators include USGS Coastal and Marine Geology Program colleagues in Woods Hole, Massachusetts, and St. Petersburg, Florida, and researchers with the USGS Western Ecological Research Center on Mare Island, California. Academic collaborators include those from University of Hawaiʻi, Oregon State University, University of Alaska, University of California, Scripps Institution of Oceanography, and University of Cantabria (Spain). Also involved are colleagues and federal partners from such agencies as the U.S. National Park Service, U.S. Fish and Wildlife Service, U.S. Department of Defense, and National Oceanic and Atmospheric Administration.
- Science
Below are all of the research topics associated with this project.
- Data
Below are data releases associated with this project.
Filter Total Items: 14No Result Found - Multimedia
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- Publications
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Filter Total Items: 93Towards determining spatial methane distribution on Arctic permafrost bluffs with an unmanned aerial system
Arctic permafrost stores vast amounts of methane (CH4) in subsurface reservoirs. Thawing permafrost creates areas for this potent greenhouse gas to be released to the atmosphere. Identifying ‘hot spots’ of methane flux on a local scale has been limited by the spatial scales of traditional ground-based or satellite-based methane-sampling methods. Here we present a reliable and an easily replicableAuthorsFerdinand K. J. Oberle, Ann E. Gibbs, Bruce M. Richmond, Li H. Erikson, Mark P. Waldrop, Peter W. SwarzenskiPhysical 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 GilmourHydrodynamics 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. BuckleyGeochemical 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. StorlazziAssessing and communicating the impacts of climate change on the Southern California coast
Over the course of this and the next century, the combination of rising sea levels, severe storms, and coastal erosion will threaten the sustainability of coastal communities, development, and ecosystems as we currently know them. To clearly identify coastal vulnerabilities and develop appropriate adaptation strategies for projected increased levels of coastal flooding and erosion, coastal managerAuthorsLi H. Erikson, Patrick L. Barnard, Andrea C. O'Neill, Patrick Limber, Sean Vitousek, Juliette Finzi Hart, Maya Hayden, Jeanne M. Jones, Nathan J. Wood, Michael Fitzgibbon, Amy C. Foxgrover, Jessica LoveringMeteorologic, 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. CuttlerMost 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. McCallMechanisms 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. StorlazziNonhydrostatic and surfbeat model predictions of extreme wave run-up in fringing reef environments
The accurate prediction of extreme wave run-up is important for effective coastal engineering design and coastal hazard management. While run-up processes on open sandy coasts have been reasonably well-studied, very few studies have focused on understanding and predicting wave run-up at coral reef-fronted coastlines. This paper applies the short-wave resolving, Nonhydrostatic (XB-NH) and short-wavAuthorsChristopher H. Lashley, Dano Roelvink, Ap R. van Dongeren, Mark L. Buckley, Ryan J. LoweVulnerability of coral reefs to bioerosion from land-based sources of pollution
Ocean acidification (OA), the gradual decline in ocean pH and [ ] caused by rising levels of atmospheric CO2, poses a significant threat to coral reef ecosystems, depressing rates of calcium carbonate (CaCO3) production, and enhancing rates of bioerosion and dissolution. As ocean pH and [ ] decline globally, there is increasing emphasis on managing local stressors that can exacerbate the vulnerabiAuthorsNancy G. Prouty, Anne Cohen, Kimberly K. Yates, Curt D. Storlazzi, Peter W. Swarzenski, Darla WhiteA Bayesian-based system to assess wave-driven flooding hazards on coral reef-lined coasts
Many low-elevation, coral reef-lined, tropical coasts are vulnerable to the effects of climate change, sea level rise, and wave-induced flooding. The considerable morphological diversity of these coasts and the variability of the hydrodynamic forcing that they are exposed to make predicting wave-induced flooding a challenge. A process-based wave-resolving hydrodynamic model (XBeach Non-HydrostaticAuthorsS. G. Pearson, Curt D. Storlazzi, A. R. van Dongeren, M. F. S. Tissier, A. J. H. M. Reniers - Web Tools
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Filter Total Items: 28 - Partners
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