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Coasts Glossary

Our Nation’s coast is almost 100,000 miles and is home to more than 40% of population and supports critical habitat. USGS coastal scientists work to better understand these dynamic ecosystems to help safeguard coastal communities and conserve valuable resources. Get familiar with coasts terminology featured in our Glossary.

0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Animation shows tides washing away brown mud from the shoreline and eroding green marshgrass. A graph follows the tide.

Accretion

the gradual accumulation of soil layers
People recreating on the Chattahoochee River in Atlanta.

Anthropogenic

human-caused, or derived from the actions of people

B

Coastal wetland ecosystems in Jamaica Bay, New York,

Blue carbon

carbon captured by the world's ocean and coastal ecosystems

C

Uncovering the Ecosystem Service Value of Carbon Sequestration in National Parks. Photo by Robert Crootof, NPS.

Carbon sequestration

a natural or artificial process by which carbon dioxide is removed from the atmosphere and held in solid or liquid form
Authigenic carbonate nodule

Carbonate

a salt of the anion H2CO3, typically by reaction with carbon dioxide
View looks along an ice-rich permafrost bluff that is eroding muddy chunks of tundra onto a sandy beach.

Coastal resilience

building the ability of a community to “bounce back” after hazardous events such as hurricanes, coastal storms, and flooding – rather than simply reacting to impacts
salt marsh and mangrove trees in coastal wetland

Coastal wetlands

saltwater and freshwater wetlands located within coastal watersheds

E

Cars, pedestrians, and homes alongside a coast with big waves hitting the cliffs and sections of the cliff have collapsed.

Erosion

the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location, and then transports it to another location where it is deposited.
green marshy wetland with a cloudy sky

Estuaries

areas where a freshwater river or stream meets the ocean
Aerial photo of estuary

Estuary

an area where a freshwater river or stream meets the ocean

G

underwater features

Geomorphic

relating to the form of the landscape and other natural features of the earth's surface
Research themes thumbnail:  Oceanside beaches-dunes

Geomorphology

the shape and/or form of the landscape and other natural features of the earth's surface

I

illustration showing complete inundation of an island

Inundation

When water levels are high enough such that the dunes (and potentially areas behind them) are completely submerged

L

Coastal bathymetry, St. Thomas, US Virgin Islands, mapped using lidar and depicted with false-color

Lidar

light detection and ranging; using plane-based lasers to measure the elevation of the surface of the Earth

O

Dauphin Island overwash

Overwash

When water pushes sand landward behind the dune crest, potentially lowering or flattening the dunes

P

Green frog

Pathogen

a bacterium, virus, or other microorganism that can cause disease
ice-rich permafrost

Permafrost

a thick subsurface layer of soil that remains frozen throughout the year, occurring chiefly in polar regions

T

Image of a healthy river and terrestrial ecosystem inteface.

Terrestrial

of or relating to the earth or its living things
Topobathymetric elevation model of New England/Cape Cod

Topobathymetric

referring to the shape of the Earth's surface both above (topo) and below (bathy) sea level

W

Image taken by USGS scientists on Madeira Beach, Florida, during a winter storm event.

Wave runup

the rise of water level due to waves breaking on the shoreline