Oceanography Midterm Vocab

Albedo

The proportion of incident solar radiation reflected by a surface, with implications for energy balance and climate feedback mechanisms

Anadromous

Referring to organisms that primarily reside in saltwater but undertake significant migrations to freshwater systems for reproductive purposes

Arctic amplification

A phenomenon wherein climate change disproportionately accelerates warming in Arctic regions due to feedback loops like diminished sea ice and increased heat absorption

Asthenosphere

The highly viscous, mechanically weak region of the upper mantle beneath the lithosphere that facilitates tectonic plate motion through its semi-plastic behavior

Barrier island

Elongated coastal landforms composed of sediment, dynamically shaped by tidal and wave activity, serving as buffers against storm surge and erosion

Bathymetry

The scientific measurement and representation of underwater topography, critical for understanding seafloor morphology and marine processes

Broodstock

Mature, reproductively viable aquatic organisms selected for their genetic traits to propagate offspring in aquaculture systems

Buoyancy

The net upward force exerted on an object submerged in a fluid, governed by the density differential between the object and the fluid

Calcium carbonate

A crystalline compound utilized in the structural components of marine organisms, whose solubility is influenced by temperature and ocean acidification

Carbon dioxide

A key component of Earth's carbon cycle, integral to oceanic carbon sequestration and a primary driver of acidification via dissolution and carbonate equilibrium

Catadromous

Describes species that migrate from freshwater to marine environments to complete their reproductive cycles, exemplified by the European eel

Continental rise

A depositional region at the base of the continental slope formed by sediment accumulation transported via submarine canyons

Convection cells

Large-scale circulation patterns in fluids driven by temperature gradients, fundamental to heat transfer within Earth's mantle and the atmosphere

Coriolis effect

The deflection of moving objects caused by Earth's rotation, shaping ocean gyres and atmospheric circulation in a hemispheric context

Current

Directed, large-scale movements of ocean water influenced by wind, temperature gradients, salinity differences, and Earth's rotation

Dead zone

Hypoxic or anoxic regions in marine or freshwater systems caused by nutrient loading, often resulting in ecosystem collapse and loss of biodiversity

Density

A scalar property defined as mass per unit volume, crucial in determining stratification, buoyancy, and ocean circulation dynamics

Diatoms

Photosynthetic microalgae encased in silica frustules, forming the foundation of many marine trophic systems and playing a role in biogeochemical cycling

El Niño

A periodic climate anomaly marked by weakened trade winds and elevated sea surface temperatures in the equatorial Pacific, disrupting global weather patterns

Estuary

Semi-enclosed coastal systems where fluvial freshwater mixes with saline ocean water, creating unique gradients that support biodiverse ecosystems

Eutrophication

The excessive enrichment of aquatic systems with nutrients, leading to algal blooms, oxygen depletion, and habitat degradation

Fetch

The uninterrupted distance over which wind energy is transferred to the surface of a body of water, influencing wave development and energy

Fjord

Deep, glacially carved marine inlets with steep sides, typically formed in high-latitude regions and characterized by stratified water columns

Glacier

Persistent, slow-moving masses of ice and snow formed through compaction and recrystallization, integral to hydrological cycles and sea level regulation

Greenhouse effect

The process by which specific atmospheric gases absorb and re-emit infrared radiation, enhancing thermal retention within Earth's atmosphere

Groin

Shore-perpendicular structures designed to disrupt longshore sediment transport, altering erosion and deposition dynamics along coastlines

Grounding line

The juncture where a glacier or ice sheet transitions from being grounded on bedrock to floating on the ocean, critical in ice mass balance studies

Gyre

Large-scale ocean circulation systems formed by wind patterns and Coriolis forces, facilitating heat redistribution and nutrient transport

Hatchery

Controlled environments for artificial propagation, incubation, and rearing of aquatic species to support fisheries and conservation efforts

Hot spot

A stationary plume of magma rising from the mantle, creating volcanic activity that can form island chains as tectonic plates move over it

Hydrogen bond

A weak electrostatic attraction between polar molecules, particularly influential in water's unique thermal, solvent, and cohesive properties

Ice core

Cylindrical samples extracted from glaciers and ice sheets, containing stratified records of past atmospheric composition and climate

Ice sheet

Massive, continent-spanning accumulations of glacial ice, storing vast amounts of Earth's freshwater and influencing global sea levels

Ice shelf

Thick, floating extensions of ice sheets that interact with ocean currents, playing a pivotal role in ice sheet dynamics and stability

Jetty

An engineered structure extending into a body of water to protect navigation channels and influence sediment deposition patterns

Keystone species

Organisms whose ecological role disproportionately affects the structure, stability, and function of their ecosystem

Krill

Small, shrimp-like crustaceans central to polar food webs, serving as primary prey for whales, seals, and seabirds

Limiting factor

Any environmental variable that constrains biological processes or population growth when suboptimal

Lithosphere

The rigid outermost layer of Earth, composed of the crust and uppermost mantle, segmented into tectonic plates

Littoral zone

The dynamic interface between terrestrial and marine ecosystems, subject to tidal and wave processes

Longshore drift

The lateral movement of sediment along coastlines driven by oblique wave approach, shaping beaches and spits

Mantle

The viscous layer beneath Earth's crust, composed of silicate materials and responsible for convective heat transfer driving plate tectonics

Mid-Atlantic Ridge

An underwater mountain range formed by divergent tectonic plates, a site of active volcanism and new crust formation

Nitrates (nutrients)

Essential nitrogen compounds for plant growth, often a byproduct of agricultural runoff, contributing to eutrophication in aquatic systems

Nitrogen fixation

The biological or chemical conversion of atmospheric nitrogen into ammonia or related compounds, enabling its use in ecosystems

Northwest Passage

A historically sought Arctic sea route connecting the Atlantic and Pacific Oceans, now increasingly navigable due to melting sea ice

Ocean acidification

A reduction in ocean pH caused by the uptake of anthropogenic CO₂, impairing calcification processes in marine organisms

Oyster

A filter-feeding bivalve mollusk integral to estuarine ecosystems, serving as natural water purifiers and habitat builders

Ozone

A triatomic oxygen molecule forming a layer in the stratosphere, vital for absorbing ultraviolet radiation but vulnerable to anthropogenic damage

Pacific garbage patch

A massive accumulation of buoyant plastics and debris within the North Pacific Gyre, representing a critical environmental challenge

Paris Accord

An international treaty aimed at limiting global temperature rise through commitments to reduce greenhouse gas emissions

Penguin

Flightless seabirds adapted to polar environments, relying on insulated feathers and fat reserves for thermoregulation in icy waters

Plastic

Synthetic polymers with high durability and resistance to degradation, causing persistent pollution in marine ecosystems

Polar bear

A top predator in Arctic ecosystems, dependent on sea ice for hunting seals, with populations threatened by climate change

Precautionary principle

A risk management approach emphasizing caution and preventative action in the face of scientific uncertainty about environmental impacts

Primary productivity

The rate of organic matter production by autotrophs through photosynthesis or chemosynthesis, forming the energy base of ecosystems

Remotely Operated Vehicle (ROV)

Unmanned submersibles used for deep-sea exploration and research, often equipped with cameras, sensors, and robotic arms

Salinity

The concentration of dissolved salts in water, influencing density, buoyancy, and thermohaline circulation in oceans

Sea breeze

A localized wind pattern resulting from differential heating of land and sea surfaces, with cooler air moving inland during the day

Sea ice

Frozen seawater forming a dynamic layer at polar ocean surfaces, critical for albedo, habitat, and ocean-atmosphere interactions

Shallow water wave

Waves whose behavior is influenced by the seafloor due to depths less than half their wavelength, altering speed and height

Side-scan sonar

A remote sensing technique that uses reflected sound waves to produce detailed images of the seafloor's surface features

Subduction

The process where one tectonic plate descends beneath another into the mantle, generating volcanic arcs and deep ocean trenches

Territorial waters

The marine area extending 12 nautical miles from a nation’s coastline, under its sovereignty per international law

Thermal expansion

The increase in water volume as it absorbs heat, a key driver of contemporary sea level rise

Thermocline

A distinct layer in the ocean where temperature changes rapidly with depth, acting as a barrier to vertical mixing

Thermohaline circulation

A global-scale ocean circulation pattern driven by differences in temperature and salinity, crucial for heat and nutrient distribution

Trade winds

Persistent easterly winds in tropical latitudes, driven by the Hadley cell circulation and influencing global weather and ocean currents

Tsunami

A series of powerful ocean waves generated by seismic activity, landslides, or volcanic eruptions, often causing catastrophic coastal damage

Wake

The turbulent flow of water left behind a moving vessel or object, influencing wave dynamics and erosion

Walker Circulation

A large-scale atmospheric circulation over the equatorial Pacific, influencing El Niño and La Niña events through shifts in trade winds and pressure

Watershed

A drainage basin where all precipitation converges into a single water body, crucial for understanding hydrological and sedimentary processes

Wave frequency

The number of wave crests passing a fixed point per unit of time, influencing energy transfer in aquatic systems

Wave period

The time interval between consecutive wave crests at a fixed point, determining wave energy and behavior

Wavelength

The horizontal distance between two consecutive crests or troughs, a key parameter in wave mechanics