An official website of the United States government. Here's how you knowHere's how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Latest Earthquake | Chat Share
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.
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.
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 coastsThe 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 islandsSea 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 NorthwestEssential 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 beachesFor 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 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.
Prediction of Flooding Now and Into the Future: a geonarrative on coastal storms
Alaska's north coast has been home to indigenous communities for centuries. Changing coastlines threaten important infrastructure and historic sites that support indigenous communities. Changing coastlines also can potentially reduce habitat for Arctic wildlife, such as polar bears, shorebirds, and walruses. Oil- and gas-related development sites and U.S. Department of Defense installations
U.S. Geological Survey scientists have shown that along with providing food, tourism, and biodiversity, coral reefs also protect dollars and lives. This interactive geonarrative introduces the USGS research to understand the role of US coral reefs in coastal protection.
Exploring Shoreline Positions of the United States From the 1800s To The Present. This geonarrative explains how the USGS derives shorelines from various data sources, and how shoreline change rates are generated from these data. The Natural Hazards Mission Area programs of the USGS develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation.
U.S. Geological Survey researchers develop tools to forecast coastal change hazards. This geonarrative features research and tools developed to forecast real-time coastal change.
USGS Coastal Change Hazards research provides scientific tools to protect lives, property, and the economic well being of the Nation. The mission of the USGS Coastal Change Hazards Program is to provide research and tools to protect lives, property, and the economic well-being of the Nation. This is a story map that introduces the value of our coasts and the threats they face with global change.
Below are news stories associated with this project.
A new multidisciplinary case study from USGS and collaborators looks at how even modest sea-level rise threatens coastal communities, infrastructure...
USGS studies coastal change along Alaska’s 66,000 miles of complex coastline - which stands as a tremendous resource to the Nation.
The USGS formally announces the establishment of a program focus on Coastal Change Hazards to coordinate research and tools needed to respond to...
The USGS is excited to present a series of Coastal Change Hazards geonarratives that will take you on a journey to learn more about coastal change...
From October 9–15, USGS personnel surveyed beaches and the adjacent ocean floor along Monterey Bay’s northern coast.
From September 12–14, scientists from the USGS Pacific Coastal and Marine Science Center used all-terrain vehicles and small watercraft to map the...
Scientists from the USGS Pacific Coastal and Marine Science Center lead a suite of research projects that provided foundational science to California...
In July 2018, three USGS Pacific Coastal and Marine Science Center researchers installed instruments and hosted a community outreach event.
Coastal cliffs from Santa Barbara to San Diego might crumble at more than twice the historical rate by the year 2100 as sea levels rise.
A deluge of media coverage followed publication of a USGS-led study showing that sea-level rise and wave-driven flooding could make many low-lying...
Sea-level rise and wave-driven flooding will negatively impact freshwater resources on many low-lying atoll islands in such a way that many could be...
Sea-level rise and wave-driven flooding could introduce saltwater so frequently into atoll islands’ freshwater resources that many will be...
Below are partners associated with this project.