The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around 620,000 kilometres (390,000 mi) of coastline. Coasts are important zones in natural ecosystems, often home to a wide range of biodiversity. On land, they harbor important ecosystems such as freshwater or estuarine wetlands, which are important for bird populations and other terrestrial animals. In wave-protected areas they harbor saltmarshes, mangroves or seagrasses, all of which can provide nursery habitat for finfish, shellfish, and other aquatic species. Rocky shores are usually found along exposed coasts and provide habitat for a wide range of sessile animals and various kinds of seaweeds. Along tropical coasts with clear, nutrient-poor water, coral reefs can often be found between depths of 1–50 meters.
Puget Sound is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected marine waterways and basins, with one major and two minor connections to the open Pacific Ocean via the Strait of Juan de Fuca—Admiralty Inlet being the major connection and Deception Pass and Swinomish Channel being the minor.
A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shells or coralline algae. Sediments settle in different densities and structures, depending on the local wave action and weather, creating different textures, colors and gradients or layers of material.
Coastal erosion is the loss or displacement of land, or the long-term removal of sediment and rocks along the coastline due to the action of waves, currents, tides, wind-driven water, waterborne ice, or other impacts of storms. The landward retreat of the shoreline can be measured and described over a temporal scale of tides, seasons, and other short-term cyclic processes. Coastal erosion may be caused by hydraulic action, abrasion, impact and corrosion by wind and water, and other forces, natural or unnatural.
A bulkhead is a retaining wall, such as a bulkhead within a ship or a watershed retaining wall. It may also be used in mines to contain flooding.
Beach nourishment describes a process by which sediment, usually sand, lost through longshore drift or erosion is replaced from other sources. A wider beach can reduce storm damage to coastal structures by dissipating energy across the surf zone, protecting upland structures and infrastructure from storm surges, tsunamis and unusually high tides. Beach nourishment is typically part of a larger integrated coastal zone management aimed at coastal defense. Nourishment is typically a repetitive process since it does not remove the physical forces that cause erosion but simply mitigates their effects.
Puget Sound is a deep inlet of the Pacific Ocean in Washington, extending south from the Strait of Juan de Fuca through Admiralty Inlet. It was explored and named by Captain George Vancouver for his aide, Peter Puget, in 1792.
Puget Sound salmon recovery is a collective effort of federal, state and local authorities and non-profit coalitions of universities, scientists, business and industry aimed at restoring Pacific salmon and anadromous forms of Pacific trout (Oncorhynchus) within the Puget Sound region. The Puget Sound lies within the native range of the Pacific Salmon (Oncorhynchus) and two sea-run forms of Pacific trout, the coastal rainbow trout or steelhead and coastal cutthroat trout. Populations of Oncorhynchus have seen significant declines since the middle of the 19th century due to over fishing, habitat loss, pollution and disease. Salmon species residing in or migrating through the Puget Sound to spawning streams include Chum, Coho, Chinook, Sockeye, and Pink salmon. Pacific salmon require freshwater rivers for spawning and most major tributaries of the Puget Sound have salmon, steelhead and cutthroat trout spawning runs.
Coastal geography is the study of the constantly changing region between the ocean and the land, incorporating both the physical geography and the human geography of the coast. It includes understanding coastal weathering processes, particularly wave action, sediment movement and weather, and the ways in which humans interact with the coast.
Coastal management is defence against flooding and erosion, and techniques that stop erosion to claim lands. Protection against rising sea levels in the 21st century is crucial, as sea level rise accelerates due to climate change. Changes in sea level damage beaches and coastal systems are expected to rise at an increasing rate, causing coastal sediments to be disturbed by tidal energy.
Goleta Beach is a region of coastline located near Goleta, California, just east of the University of California, Santa Barbara (UCSB) campus. A portion of the shore of Goleta Bay is managed by the County of Santa Barbara, as the Goleta Beach County Park (GBCP). The beach itself is partly man-made as sand was spread onto an existing sandspit in 1945. The beach is a seasonal habitat for migrating shorebirds, including the snowy plover, an endangered species, and is occasionally closed due to nourishment efforts.
Double Bluff Beach is a beach and headland on Whidbey Island in the U.S. state of Washington. The beach tidelands themselves comprise Double Bluff State Park. The uplands and access areas are operated by Island County, Washington as Double Bluff County Park and Beach Access.
Beach evolution occurs at the shoreline where sea, lake or river water is eroding the land. Beaches exist where sand accumulated from centuries-old, recurrent processes that erode rocky and sedimentary material into sand deposits. River deltas deposit silt from upriver, accreting at the river's outlet to extend lake or ocean shorelines. Catastrophic events such as tsunamis, hurricanes, and storm surges accelerate beach erosion.
Sedimentary budgets are a coastal management tool used to analyze and describe the different sediment inputs (sources) and outputs (sinks) on the coasts, which is used to predict morphological change in any particular coastline over time. Within a coastal environment the rate of change of sediment is dependent on the amount of sediment brought into the system versus the amount of sediment that leaves the system. These inputs and outputs of sediment then equate to the total balance of the system and more than often reflect the amounts of erosion or accretion affecting the morphology of the coast.
Sand dune stabilization is a coastal management practice designed to prevent erosion of sand dunes. Sand dunes are common features of shoreline and desert environments. Dunes provide habitat for highly specialized plants and animals, including rare and endangered species. They can protect beaches from erosion and recruit sand to eroded beaches. Dunes are threatened by human activity, both intentional and unintentional. Countries such as the United States, Australia, Canada, New Zealand, the United Kingdom, and Netherlands, operate significant dune protection programs.
Washdyke Lagoon is a brackish shallow coastal lagoon approximately 1 kilometre (0.62 mi) north of Timaru, South Canterbury, New Zealand. The lagoon has drastically reduced in size since 1881 when it was approximately 253 hectares, now it is less than 48 hectares (0.48 km2) in area. It is enclosed by a barrier beach that is 3 kilometres (1.9 mi) long and 3 metres (9.8 ft) above high tide at its largest point. The reduced lagoon size is due to the construction of the Timaru Port breakwater which is preventing coarse sediments from reaching and replenishing Washdyke Barrier. This is important as the lagoon and the surrounding 250 hectares are classified as a wildlife refuge and it demonstrates the role human structures have on coastline evolution.
The environmental issues on Maury Island are linked to broader Puget Sound environmental issues, which include concerns regarding declining salmon and forage fish populations, degrading critical marine and shoreline habitats, and threatened species such as the Orca.
The Canterbury Bight is a large bight on the eastern side of New Zealand's South Island. The bight runs for approximately 135 kilometres (84 mi) from the southern end of Banks Peninsula to the settlement of Timaru and faces southeast, exposing it to high-energy storm waves originating in the Pacific Ocean. The bight is known for rough conditions as a result, with wave heights of over 2 metres (6.6 ft) common. Much of the bight's geography is shaped by this high-energy environment interacting with multiple large rivers which enter the Pacific in the bight, such as the Rakaia, Ashburton / Hakatere, and Rangitata Rivers. Sediment from these rivers, predominantly Greywacke, is deposited along the coast and extends up to 50 kilometres (31 mi) out to sea from the current shoreline. Multiple hapua, or river-mouth lagoons, can be found along the length of the bight where waves have deposited sufficient sediment to form a barrier across a river mouth, including most notably Lake Ellesmere / Te Waihora and Washdyke Lagoon
Marine habitats are habitats that support marine life. Marine life depends in some way on the saltwater that is in the sea. A habitat is an ecological or environmental area inhabited by one or more living species. The marine environment supports many kinds of these habitats. Marine habitats can be divided into coastal and open ocean habitats. Coastal habitats are found in the area that extends from as far as the tide comes in on the shoreline out to the edge of the continental shelf. Most marine life is found in coastal habitats, even though the shelf area occupies only seven percent of the total ocean area. Open ocean habitats are found in the deep ocean beyond the edge of the continental shelf.
Dynamic revetment, also known as a "cobble berm", uses gravel or cobble-sized rocks to mimic a natural cobble storm beach for the purpose of reducing wave energy and stopping or slowing coastal erosion. Unlike seawalls, dynamic revetment is designed to allow wave action to rearrange the stones into an equilibrium profile, disrupting wave action and dissipating wave energy as the cobbles move. This can reduce the wave reflection which often contributes to beach scouring.
