Fn-Fz

FOCAL

Acronym for Programme Français Océan et Climat dans l'Atlantique Èquatorial, a program to describe and model the response of the tropical Atlantic to the wind stress on a seasonal scale. Data was obtained from nine cruises of the research vessels Capricorne (of IFREMER) and Nizery (of ORSTROM). These were undertaken every three months in the equatorial Atlantic from the Brazilian coastline to the Gulf of Guineau, starting in July 1982 and ending in August 1984. Temperature, salinity, and dissolved oxygen were measured between the surface and 500 m with a CTDO system, and horizontal velocities were measured via current profiling using a free floating surface buoy. FOCAL, along with SEQUAL, amounted to the first time an equatorial ocean was fully monitored over a period of two years. See Katz (1987), Richardson and Reverdin (1987), and Henin and Hisard (1987).

FOCI

Acronym for Fisheries-Oceanography Cooperative Investigations, a collection of NOAA programs attempting to understand the influence of environment on the abundance of various commercially valuable fish and shellfish stocks in Alaskan waters and their role in the ecosystem.

[http://www.pmel.noaa.gov/foci/]

FOCUS

Acronym for Future of Ocean Chemistry in the U.S., a workshop for chemical oceanographers held at Seabrook, South Carolina from Jan. 6-9, 1998. The goal was to evaluate the current status of research in chemical oceanography and to identify future opportunities and infrastructure needs. Similar workshops were held at the time for biological oceanography (sf OEUVRE), physical oceanography (APROPOS) and marine geology and geophysics (FUMAGES).

Areas identified as emerging objects of intense scrutiny included:

• the replacement of the classical picture of simple control of marine life by major nutrients is being replaced by numerous variations on the theme involving trace elements, organic matter cycling and/or changing nutrient ratios;
• the changes in the role of ocean margins as processors of material in the ocean due to massive human colonization of the coastline;
• the significant difference between organic matter in ocean water and rivers, despite the rivers being a large source of ocean carbon;
• the significane to chemical fluxes of fluids emanating from sediments overlying aquifers on continental margins and around rift zone flanks and crests;
• the relationship between changing climate and radiatively important gases moving between the ocean and the atmosphere;
• how the euphotic zone exports carbon to deep water in response to various physical forcings and biological transformations; and
• the advances in geochemical concepts and analytical technology allowing the measurement and interpretation of the earth's past climates and chemical changes.

[http://www.joss.ucar.edu/joss_psg/project/oce_workshop/focus/]

foraminifera

See Van der Zwaan (1999).

Forbes, Edward (1815-1854)

A British scientist considered by many to be the founder of the science of biological oceanography. In a time when most investigations were concerned with zoology, Forbes produced some of the first ecological generalizations about marine life to receive wide notice, the most famous of which was his recognition of distribution by bathymetric zones. His belief that no life existed in the zone below 300 fathoms was incorrect yet ultimately useful in that it did much to spur the investigation of the depths of the ocean.

Forbes was also one of the earliest systematic biogeographers, recognizing a series of provinces in the European (i.e. Arctic, Boreal, Celtic, Lusitanian, Meditteranean and Black Seas) seas. His book about these seas, Natural History of the European Seas (completed after his death by Robert Godwin-Austen), is considered to be the first treatise on marine ecology. He also was the first to consider population dynamics in the sea, and founded the science of paleoecology in a report in which he described the fossil record which might be expected in the Aegean Sea if it were to be elevated or filled with sand. See Hedgpeth (1957c).

foreshore

The sloping portion of a beach profile that lies between a berm crest (or, in its absence, the upper limit of wave swash at high tide) and the low water mark of the backrush of the wave swash at low tide. This term has been used synonymously with beach face, although the foreshore can also contain some of the flat portion of the profile below the beach face. See Komar (1976).

FORMEX

Acronym for Formation Experiment, an Antarctic CRC project to define the mechanisms underlying the formation of sea ice and its role on the formation of Antarctic Surface Waters and air-sea interaction. Specific goals including obtaining:

• quantitative estimates of the rate of formation of Antarctic surface waters in the ice pack during winter,
• quantitative estimates of the transfer of heat between ocean and atmosphere and the role of advection of surface and circumpolar deep water on these transfers, and;
• a better understanding of the processes and mechanisms involving in the mixing of Polar Zone waters with complex zone waters near the Antarctic Shelf.

[http://www.antcrc.utas.edu.au/antcrc/research/polar/oceanproc/formex.html]

fossilized mixing region

In physical oceanography, this refers to the water trapped between the depths of the summer and winter mixed layers. This is a key feature in the formation of Central Water via the process of subduction. See Tomczak and Godfrey (1994).

fossil turbulence

In the ocean, temperature microstructure that remains after the turbulence that presumably created it decays, i.e. there is no velocity microstructure. See Turner (1973).

Fourier analysis

The determination of the harmonic components of a complex waveform, i.e. the terms of a Fourier series that represents the waveform.

FOX

Acronym for Fishery-Oceanography Experiment.

f plane approximation

In oceanography, a coordinate system approximation where the Coriolis parameter $f$ is, in a simplified form of the equations of motion, assumed to be a constant. The dynamics as such take place in a plane tangent to the surface of the Earth where $f$ everywhere takes its value at the point of tangency. This approximation holds reasonably well over latitudinal distances over which $f$ doesn't vary much (i.e. a few degrees) or over a few tens of degrees near the poles where $f$ varies slowly.

The f plane equations are obtained by neglecting all terms of order $\varepsilon$ in the beta plane equations. The resulting equations (after Muller (1995)) are:

$${ {\partial u} \over {\partial t} }\,+\, u{ {\partial u} \over {\... ...u} \over {\partial y} }\,+\, w{ {\partial u} \over {\partial z} }\,-\, {f_0}v\, = \,-{1\over{\rho_*}} { {\partial\delta p} \over {\partial x}}$$

$${ {\partial v} \over {\partial t} }\,+\, u{ {\partial v} \over {\... ...v} \over {\partial y} }\,+\, w{ {\partial v} \over {\partial z} }\,-\, {f_0}u\, = \,-{1\over{\rho_*}} { {\partial\delta p} \over {\partial y}}$$

$${ {\partial w} \over {\partial t} }\,+\, u{ {\partial w} \over {\... ...{ {\partial w} \over {\partial y} }\,+\, w{ {\partial w} \over {\partial z} }\, = \, -{1\over{\rho_*}} { {\partial\delta p} \over {\partial t} }\,-\, \delta\rho g$$

$${ {\partial u} \over {\partial x} }\,+\, { {\partial v} \over {\partial y} }\,+\, { {\partial w} \over {\partial z} }\, = \,0$$

$$\left( { {\partial} \over {\partial t} }\,+\, u{ {\partial} \over... ...\over {\partial y} }\,+\, w{ {\partial} \over {\partial z} }\right)\delta\rho\, = \, w{N^2}{g \over \rho_*}$$

where $(u,v,w)$ are the horizonal and vertical components of the velocity, $f_0$ is the constant angular frequency at the given latitude,

See Gill (1982) and Muller (1995).

FRAM

Acronym for Fine Resolution Antarctic Model.

Fram Strait

A deep reaching passage with a sill depth of about 2200 m separating the Arctic Ocean to the north from the Nordic Seas to the south. This is the primary path for water exchanges between these two oceanic regions. See Hunkins (1990).

Franklin, Benjamin (1706-1790)

See Peterson et al. (1996), p. 40.

f-ratio

The ratio of new production (i.e. resulting from new nutrients coming into the system) to total production (i.e. new plus regenerated, i.e. production from nitrogen recycled within the euphotic zone). In oligotrophic waters, this is around 0.1, while in eutrophic waters is is around 0.8. See Eppley and Peterson (1979) and Garside and Garside (1993).

FRED

Acronym for Frontal Eddy Dynamics experiment. See Boicourt et al. (1998).

freezing point (of seawater)

The freezing point of seawater in $^\circ$C is given by:

$${t_f}(S,p)\,=\,-0.0575S + 1.710523\times{10^{-3}}{S^{3/2}} - 2.154996\times{10^{-4}}{S^2} - 7.53 \times {10^{-3}} p$$

which fits measurements to an accuracy of $\pm$0.004 K. See Gill (1982).

friction velocity

A velocity calculated via dimensional analysis that defines the velocity scale for the flow near a wall. This is also called the dynamic velocity. See Kagan (1995).

fringing reef

One of three main geomorphological types of coral reefs, the other two being barrier reefs and atolls. These are formed close to shore on rocky coastlines by the growth of corals and associated hydrozoans, alcyonarians and calcareous algae. Fragments of limestone derived from such bioherms are welded together by the encrusting calcareous algae as well as by the deposition of interstitial calcium carbonate cement, the latter brought about by geochemical reactions and possibly bacterial action. The zone of living corals is separated from the shore by a shallow reef flat where reduced circulation, periods of tidal emersion, and the accumulation of sediments inhibit coral growth. See Barnes and Hughes (1988).

Froude number

In fluid mechanics, a dimensionless number expressing the ratio of nonlinear advection to the pressure gradient acceleration associated with the variation of fluid depth, i.e. of the fluid speed to a measure of the internal wave speed. It is defined by

$$Fr\,=\,u / \sqrt{gH}$$

where $u$ is the flow velocity, g the gravitational acceleration, and $H$ the fluid depth, and $\sqrt{gH}$ the approximate phase speed of shallow water gravity waves. A Froude number greater than unity is indicative of what is called supercritical flow, and one less than unity of subcritical flow.

When dealing with internal waves, an internal or densimetric Froude number is defined which corresponds to the ordinary Froude number with with the reduced gravity $g'$ replacing $g$ in the above. See Turner (1973) and Houze (1993).

FRRF

Abbreviation for Fast Repetition Rate Fluorometer. See Kolber and Falkowski (1993).

fully developed sea

A hypothesized situation in wave prediction methods in which storm duration and fetch are both long enough such that energy is being dissipated internally and radiated away at the same rate at which it is being transferred from the wind to the water in the form of waves. In a fully developed sea a steady state of maximum wave development is achieved. See Komar (1976).

FUMAGES

Acronym for the Future of Marine Geology and Geophysics, a workshop for geological oceanographers and marine geophysicists held at Ashland Hills, Oregon from Dec. 5-7, 1996. The goal was to evaluate the current status of research in marine geology and geophysics and to identify future opportunities and infrastructure needs. Similar workshops were held at the time for biological oceanography (sf OEUVRE), physical oceanography (APROPOS) and chemical oceanography (FOCUS).

Common issues and directions identified in the summary of the final report include:

• the societal imperative of making rapid progress in understanding complicated, nonlinear systems;
• the central role of focused fluids in producing volcanic, tectonic, and thermal modification of the planet;
• the recognition that present-day conditions may be unrepresentative of the whole of geologic history;
• the importance of explicitly incorporating effects of and on the biosphere into marine geology and geophysics;
• the appreciation that we must move beyond steady-state models to study geological events as they happen; and
• the limitations of present funding structures and technology for problems that span the shoreline.

[http://www.joss.ucar.edu/joss_psg/project/oce_workshop/fumages/]