Abbreviation for East Australian Current.
- Early Medieval Warm epoch
See Little Climatic Optimum.
Acronym for the European Association of Remote Sensing
Laboratories. See the
EARSeL Web site.
- Earth Orientation Parameters (EOP)
Parameters used to describe the irregularities of the earth's
rotation due to the gravitational torque exerted by the moon,
sun and planets, displacement of matter in different parts of
the earth, and other excitation mechanisms. The oscillations
can be interpreted in terms of mantle elasticity, earth
flattening, the structure and properties of the core-mantle
boundary, the rheology of the core, underground water, and oceanic
and atmospheric variability. The EOP are the parameters that
provide the rotation of the ITRS to the
ICRS as a function of time.
EOP Web site.
- earth tide
To be completed.
Abbreviation for East Asian Seas Action Program.
Acronym for the European Arctic Stratospheric Ozone Experiment, the
aim of which was to take measurements of key chemical species that
would provide information to explain the observed northern
hemisphere ozone loss. See the
EASOE Web site.
- East Africa Coast Current
See Somali Current.
- East Arabian Current
A strong northeastward flowing current along the Saudi
Arabian coast. It is part of the monsoonal circulation
in the area and as such exists from about April through
October, being fully established by mid-May with
velocities ranging form 0.5-0.8 m/s. It is also part
of a strong coastal upwelling system during those months
when it flows strongest.
- East Arabian Sea Water
See Bay of Bengal Water.
- East Auckland Current
The continuation of the
East Australian Current
east of New Zealand. It forms and is part of an anticyclonic
eddy near 37 S off of East Cape. This eddy is found in
the same location throughout the years and as such is thought
to be topographically controlled. The further extension of
this current has a bimodal nature that changes seasonally.
During the summer most of its transport continues along the
New Zealand coast all the way to Chatham Rise as the
East Cape Current. In the winter part of it separates from
the shelf and continues as a zonal flow into the open
ocean, forming a temperature front near 29 S that
is distinguishable from another shallow front near
25 S called the Tropical Front, the northern limit of
eastward flow in the subtropical gyre.
See Tomczak and Godfrey (1994).
- East Australian Current
The western boundary current of the southern hemisphere in the
Pacific Ocean. It is the weakest of the world's boundary
currents, carrying about 15 Sv in the annual mean near
30 N, yet is also associated with strong current
instabilities. The relative weakness is due mostly to
the flow through the
Australasian Mediterranean Sea and the instabilities probably result
from the current following the coast and then suddenly
separating somewhere near 34 S to follow the
east coast of New Zealand (where it is known as the
East Auckland Current).
It is stronger and reaches further
inshore during the summer, with flow speeds reaching
1 m/s during the summer, and the maximum transport has been
estimated at around 30 Sv (although the intermittent nature
of the current makes such estimates somewhat suspect).
The path it follows from Australia to New Zealand is called
the Tasman Front, which separates the warmer waters of the
Coral Sea from the colder waters of the Tasman Sea. This
front develops meanders which travel westward, impinge upon
the Australian coast, and ultimately separate from the current
and form eddies. About 3 eddies are spawned per year (with
4-8 existing at any one time in recognizable form) with most
being anticyclonic or warm core eddies since the meander
closest to the coast always extends to the south.
The meandering and eddy-shedding behavior of the current
combined with its weak flow sometimes make it difficult to even
distinguish it as a current, and the location of the Tasman
Front can be meaningfully defined only in statistical terms.
See Tomczak and Godfrey (1994).
- East Cape Current
See East Auckland Current.
- East China Sea
See Tomczak and Godfrey (1994).
- East Coast Ocean Forecast System (ECOFS)
A cooperative program among NOS,
NCEP, GFDL, and
AOS to develop a system capable of
producing useful nowcast and
forecast information for the east coastal region of the
ECOFS Web site.
- East Greenland Current
See Foldvik et al. (1988).
- East Greenland Ice Stream
See Wadhams (1986).
- East Greenland Polar Front
See Johannessen (1986).
- East Icelandic Current
See Swift (1986).
- East Indian Current
A seasonal and northward flowing current found in the western part of
the Bay of Bengal from about January
until October. The weak and variable currents found early in the
year strengthen with the Northeast Monsoon, exceeding 0.5 m/s
by March and ranging from 0.7-1.0 m/s through May and June.
This current flows counter to the wind, apparently as an
extension of the
North Equatorial Current,
although a convincing dynamical explanation has yet to be offered.
The northward flow gradually weakens with the advent of the
Southwest Monsoon, with the currents to the north and close
to the shelf beginning to reverse in September. By late October,
the East Indian Current has completely reversed into the
East Indian Winter Jet.
See Tomczak and Godfrey (1994).
- East Indian Winter Jet
A seasonal southwestward flowing
western boundary current
found in the western Bay of Bengal
from late October through around late December. It features
velocities consistently above 1 m/s as it flows southwestward,
eventually turning west and following topographic contours as it
passes Sri Lanka and feeds all its waters into
the Arabian Sea. In late December
its northern part fades, eventually to become the
East Indian Current, and
the southern part merges with the developing
North Equatorial Current.
- East Korea Current
See Tsushima Current.
- East Siberian Sea
One of the seas found on the Siberian shelf in the
Arctic Mediterranean Sea.
It is located between the Laptev Sea
to the west and the Chuckchi Sea
to the east, and adjoins the
Arctic Ocean proper to the
- East Spitsbergen Current
See Pfirman et al. (1994).
- East Wind Drift
The westward flowing current close to the Antarctic continent
driven by the polar easterlies.
- eastern boundary current
See Wooster and Reid (1963).
- Eastern Equatorial Pacific (EEP)
See Wyrtki (1966).
- Eastern Mediterranean Deep Water (EMDW)
See POEM Group (1992).
- Eastern North Pacific Central Water
In physical oceanography, a water mass
formed in the region of the surface salinity maximum just south of
30 N where salinities greater than 35 are found year round.
This is reflected in the portion of ENPCW above 17 C, which
has salinities higher than those of all other water masses in the
vicinity. It is fresher than both WNPCW
and NPEW at temperatures below 17 C,
and saltier in the upper thermocline waters warmer than this.
It is bounded to the west from WNPCW
at about 170 E, and to the south from NPEW
at about 12-14 N.
See Tomczak and Godfrey (1994), p. 165.
- Eastern South Pacific Central Water
In physical oceanography, a water mass
formed between 150-180 W (by processes not yet well understood)
and separated from the
WSPCW by a gradual transition zone
from 145-100 W., from which it is distinguished as being
fresher at all T-S values. It is bound to the north by
SPEW, from which it is also distinguished
by being fresher at all T-S points, to the south by the
STC, and to the east by a not yet well understood
area having salinities as low as 34.1 east of 90 W.
See Tomczak and Godfrey (1994), p. 164.
Acronym for Eastern Tropical Pacific, a research project.
East Arabian Sea Water.
Abbreviation for Energetically Active Zones of the Ocean.
- ebb current
The tidal current existing during any time the height of the
tide is decreasing. These generally flow in a seaward
direction. This has been erroneously called ebb tide.
- ebb interval
The interval between the transit of the moon over a meridian
and the time of strength of ebb of the following tide.
- ebb strength
See strength of ebb.
- ebb tide
See falling tide.
Abbreviation for Energy Balance Bowen Ratio, a measurement system
used in the ARM program. It is a ground-based
system using in situ sensors to estimate the vertical fluxes of
sensible and latent heat at the local surface. The flux estimates
are made from measurements of net radiation, soil heat flow,
and the vertical gradients of temperature and relative humidity
via the Bowen ratio energy balance technique. See the
EBBR Web site.
Abbreviation for Eastern Boundary Current.
See energy balance model.
This describes the
variations in the ellipticity of the earth's orbit around the
sun, which varies between near circularity and an ellipticity
of about 0.06 at a main period of 413,000 years. The eccentricity
is one of three chief components of the
Milankovitch theory, the
other two being obliquity and
Abbreviation for the European Climate Computer Network, a proposal
to link the four dedicated climate computer centers in Europe, i.e.
the Hadley Center in Bracknell, Meteo-France
in Toulouse, the
IPSL in Paris, and the DKRZ in
Hamburg, to a common facility offering access to supercomputer
resources as well as a hierarchy of climate models, diagnostic
software and analysis procedures to all climate researchers in
Europe. For more details see the
ECCN Web site.
Abbreviation for European Center for Medium Range Weather Forecasts
modified in HAMburg model,
an atmospheric circulation model series developed and used
at the DKRZ. They are low-resolution versions
of the numerical weather forecasting model developed at
ECMWF, modified for climate applications.
The modifications include introducing cloud water as a prognostic
variable, the inclusion of a diurnal cycle, parameterization of
sub-grid scale processes such as radiation, cloud formation,
precipitation, convection and turbulent mixing, and the inclusion
of runoff into the ocean via a simple surface hydrology
A member of the phylum
A phylum of marine invertebrates including the classes
These are usually coelomate and radially symmetric with either
calcareous plates forming a more or less rigid skeleton or
scattered plates and spicules embedded in the body wall.
This includes such animals as sea cucumbers, sea stars, brittle
stars, sea urchins, sand dollars, sea lillies and
Introduction to the Echinodermata
U.C. Museum of Paleontology.
A class of marine invertebrates in the phylum
The more than 600 species of these are commonly known as
sea urchins and sand dollars. Most live in shallow water
although a few deep water species are known.
Acronym for European Climate and Hydrological Project on Interactions
between Vegetation, Atmosphere and Land.
Acronym for a global coupled ocean-atmosphere circulation model developed
and used at the DKRZ. It consists of a version
of ECHAM coupled with a version of
- echo integration
A process (performed in either hardware or software) whereby
echo intensities are summed over a time interval to estimate
echo energy. This is used to quantify scattering from
schools of fish or plankton in bioacoustics.
- echo ranging
- echo sounder
Acronym for Etudes Climatiques dans l'Atlantique Tropical, a
multidisciplinary program designed to become the French
contribution of CLIVAR in
the tropical Atlantic. The PIRATA
program will be part of ECLAT.
ECLAT Web site.
Acronym for the Experimental Cloud Lidar Pilot Study.
See Platt and co authors (1994).
- eclipse year
The interval of time between two successive passages of the Sun
through the same node of the Moon's orbit. It is equal to
The great circle in which the plane containing the centers of the
Earth and the Sun cuts the celestial sphere.
Abbreviation for European Centre for Medium-Range Weather Forecasts, an
international organization whose objectives are to develop numerical
methods for medium-range weather forecasting, prepare medium-range
weather forecasts for distributions to the meteorological services
of the member states on a regular basis, perform research directed
towards improving forecasts, and collecting and storing appropriate
ECMWF Web site.
Acronym for European Collaboration on CO2 Responses applied to Forests
and Trees, an EU funded program whose objectives are to: (1) define
and describe growth processes in trees that are affected by the
rise in atmospheric CO and the increase in temperature; (2) develop
process-based models that include the explicit representation of
the biochemical and physiological processes involved in those
growth processes; and (3) the test the models against flux
measurements made with eddy covariance measuring systems to also
use them to predict the consequences of global change.
ECOCRAFT Web site.
Acronym for European Consortium for Ocean Drilling, an organization
through which scientists from Europe participate in the
ECOD Web site.
East Coast Ocean Forecast System.
- ecogeographical rule
A rule that summarizes observations about how warm-blooded species
vary in a regular way with climate.
- ecological efficiency
In marine ecology, the amount of energy extracted from a given
trophic level divided by that
supplied to the same trophic level. This is the product of
two other coefficients, the
ecotrophic efficiency and
the growth efficiency.
See Barnes and Hughes (1988).
- ecological race
Acronym for European Committee for Ocean and Polar Sciences.
All the individuals, species and populations in a spatially defined
area, the interactions among them, and those between the
organisms and the abiotic environment.
See Heywood (1995).
- ecotrophic efficiency
In marine ecology, the proportion of the annual production of
a trophic level
taken by consumers.
This is one of two factors comprising the
See Barnes and Hughes (1988).
A genetically distinct
local population of a species made up of individuals with similar
environmental tolerances and that are specialized to meet local
environmental conditions. These populations show minor changes
in morphology and/or physiology but are still able to interbreed,
although they have to potential to develop in a new species. This
is also called an ecological race.
See Collinson (1988).
Abbreviation for Experimental Climate Prediction Center,
located at the Scripps Institution of Oceanography.
The center develops new methods for predicting short to
long term climate variations.
ECPC Web site.
Abbreviation for the European Climate Support Network.
ECSN Web site.
Abbreviation for equatorial cold tongue, a tongue of relatively
cold water between the NWT and the
SWT at the eastern boundary of the
WPWP. It is located on the equator and
disappears during an El Nino event.
See Ho et al. (1995).
A biologically active substance whose presence
in minute quantities can control
marine productivity. Laboratory experiments have demonstrated
that many substances excreted by lower forms of marine life can
either promote or inhibit growth, although there is no direct
evidence that they are important under natural conditions.
The most extensively investigated growth promoting compounds are
vitamin B12, B1 (thiamine) and biotin.
See Riley and Chester (1971).
Abbreviation for EROS Data Center, a
data management, systems development, and research field center
of the USGS's National Mapping Division. It was established in
the early 70s to receive, process and distribute data from
NASA Landsat satellites and holds the world's largest collection
of space and aircraft acquired imagery of the Earth. EDC also
develops and oeprates advanced systems for receiving, processing,
distributing, and applying land related Earth science, mapping,
and other other geographic data and information.
EDC Web site.
- eddy conduction
See eddy heat flux.
- eddy conduction coefficient
See eddy conductivity.
- eddy conductivity
The exchange coefficient for the transfer of heat by eddies
in turbulent flow, i.e. eddy heat flux. This is also
called the eddy conduction coefficient.
- eddy diffusivity
- eddy heat conduction
See eddy heat flux.
- eddy heat flux
In physical oceanography, the total meridional heat transport due
to mesoscale eddies. This has also been used to refer to the
correlation of time-dependent fluctuations of velocity and
temperature across a section, which is not indicative of the
total heat transport due to eddies. Eddies can also induce
a thermally driven, overturning cell in subtropical gyres that
is analogous to the Ferrel cell
in the atmosphere. This cell contributes to the time-averaged
transport and its contribution may be as large as that of the
This is also called eddy conduction or eddy heat conduction.
See Cox (1985).
- eddy-induced transport velocity
An additional velocity which must be added to the large-scale
velocity to properly advect large-scale tracers in numerical
circulation models. This is due to the effective transport
velocity not being equivalent to the Langrangian-mean
velocity when the diffusivity is not spatially homogeneous.
See Gent et al. (1995).
- eddy viscosity
A coefficient used to achieve
closure in the
Reynolds equations for
turbulent flow. The assumption is made that the
Reynolds stresses are related
to the velocity gradients of the flow by a viscosity analogous
to the molecular viscosity, i.e. a turbulent
or eddy viscosity.
The utility of the analogy is strained by the fact that while
the molecular viscosity is a property of the fluid, the eddy
viscosity is a property of the flow. As such the specification
of the eddy viscosity has more than a little of the air of the ad hoc
about it since it is usually found via a trial-and-error procedure
wherein it is varied until a numerically simulated flow reasonably
replicates a known flow. The value thus obtained diagnostically
is then used for prognostic simulations, a procedure that is
questionable due to the abovementioned fact of the eddy viscosity
being a property of the flow rather than the fluid. That is, if the flow
is remarkably different, then the eddy viscosity may also be
In the ocean eddy viscosity values range typically from
10 to 10**5 m2/s in the horizontal and from 10**-5 to 10**-1 m2/s in
the vertical, with both values more often found towards the higher
ends of their ranges.
- edge wave
A wave which travels parallel to a coastline with crests normal
to the coastline. The height of the wave diminishes rapidly
Acronym for European Directory of Marine Environmental Data,
a computer searchable directory of datasets relating to the
marine environment compiled in collaboration with research
and/or data centers in eleven European countries.
The aim of EDMED is to provide a comprehensive reference
to the marine environmental data held within Europe to provide
marine scientists, engineers, and policy makers with the
means of identifying potentially useful data sets.
It was developed and is coordinated by the
BODC and was funded by
EDMED Web site.
Abbreviation for Eddy Damped Quasi-Normal Markovian, a subfilter
closure model applied in spectral wavenumber space rather than
physical space which considers interactions between resolved
and subfilter wavenumbers by considering the statistics
of their possible interactions.
The EDQNM achieves closure by modeling the 4th spectral
moments. The is one of several closure techniques used when applying
large eddy simulation model.
See Mason (1994).
Abbreviation for European Earth Observation System, an initiative
based on a partnership between the ESA
and the EC to provide a framework within which
the data, technical knowledge and other information within Europe
can be accessed as a coherent whole.
EEOS Web site.
Abbreviation for eastern equatorial Pacific.
Abbreviation for Earth and Environmental Sciences Center, a division
of PNL whose mission is to solve society's environmental
and earth resources problems through interdisciplinary work founded
on developing research capabilities maintained as a national resource
by the DOE. See the
EESC Web site.
Abbreviation for Exclusive Economic Zone.
Acronym for European Field Experiment in Desertification
- effective scattering cross-section
The ratio of backward scattering intensity to density of
See Kagan (1995).
- effective rainfall
The proportion of precipitation that is not evaporated and is therefore
available for various uses. It is defined as precipitation less
evaporation and normally computed monthly or annually.
- effective transport velocity
The sum of the large-scale velocity and the
eddy-induced transport velocity. This is velocity at which
tracers are advected in large-scale circulation models.
See Gent et al. (1995).
- e-folding time
The time it takes a system to reduce an imposed displacement to
a factor of 1/e of the displaced value. This is a common way
of expressing the
equilibration time of a system.
The e-folding concept is often applied
to distances as well as times.
Abbreviation for Eddy-resolving General Circulation Model.
European Geophysical Society.
Abbreviation for EGS Working Group on
Abbreviation for extremely high frequency, an electromagnetic spectrum
waveband ranging from 30 to 300 GHz.
Acronym for the European Emiliania huxleyi program,
a comprehensive experimental and modeling program focused on
the calcium carbonate and organic carbon productivity
and ocean carbon flux induced by E. huxleyi in the
Northeast Atlantic region. It is a component of and
complementary to the GEM program.
This project aims to characterize the nonlinear nature of
the biological involvement in ocean chemistry and the
coupling of the fluxes of particulate organic carbon (POC)
and particulate inorganic carbon (PIC).
The fundamental objective is the improve understanding of
the processes involved in the growth, distribution and
role of E. huxleyi in the oceanic carbon cycle.
The specific aims include the morphological and genetic
characterization of clones from different areas and elucidation
of the life cycle; characterization of PIC, POC, biomarker
and CO productivity as a function of cellular and molecular
organization and life cycle stages; parallel mesocosm experiments;
quantification of these processes in natural blooms at different
stages of development and development of carbon budgets for
well defined spring bloom conditions; and the development
of descriptive and predictive models.
entrainment interfacial layer.
Abbreviation for Echo Integration-Midwater Trawl.
A unit equal to 6.022 x quanta, or one mole of
Acronym for European Incoherent Scatter Radar.
Acronym for European Ice Sheet Modelling Initiative, an LESC
project whose aim is to examine the critical links between global
climate change and ice sheets by improving mathematical modeling
in a number of key areas.
EISMINT Web site.
Abbreviation for eddy kinetic energy.
- Ekman current meter
A mechanical current meter that comprises a propeller with
a mechanism to record the number of revolutions, a compass
and a recorder with which to record the direction, and a vane
that orients the instrument so the propellor faces the current.
It is mounted on a free-swinging vertical axis suspended from
a wire and has a weight attached below. The balanced propellor,
with from four to eight blades, rotates inside a protective
ring. The position of a lever controls the propeller. In
down position the propellor is stopped and the instrument is
lowered, after which reaching the desired depth a weight called
a messenger is dropped to move the lever into the middle position
which allows the propeller to turn freely. When the measurement
has been taken another weight is dropped to push the level to
its highest position at which the propeller is again stopped.
The propeller revolutions are counted via a simple
mechanism that gears down the revolutions and counts them
on an indicator dial. The direction is indicated by a
device connected to the directional vane that drops a small
metal ball about every 100 revolutions. The ball falls into
one of thirty-six compartments in the bottom of the compass
box that indicate direction in increments of 10 . If the
direction changes while the measurement is being performed
the balls will drop into separate compartments and a weighted
mean is taken to determine the average current direction.
This is a simple and reliable instrument whose main disadvantage
is that is must be hauled up to be read and reset after each
measurement. Ekman solved this problem by designed a repeating
current meter which could take up to forty-seven measurements
before needing to be hauled up and reset. This device used
a more complicated system of dropping small numbered metal balls at
regular intervals to record the separate measurements.
See Sverdrup et al. (1942).
- Ekman repeating current meter
See Ekman current meter.
- Ekman dynamics
In oceanography, the process of surface wind stress driving a
relatively shallow upper ocean flow that transports water to the
left/right and the southern/northern hemisphere.
- Ekman layer
To be completed.
- Ekman number
In oceanography, a dimensionless number expressing the ratio of
frictional (or viscous) to Coriolis forces.
It can be expressed as
where is the kinematic viscosity, D a vertical length scale,
and f the Coriolis parameter.
A small Ekman number can be interpreted as the condition that frictional
forces are sufficiently weak such that the natural decay time due to
viscous dissipation in the Ekman layer is large compared to a rotation
period, i.e. that the spin-down is dominated by rotational rather
than frictional processes.
See Kraus and Businger (1994) (p. 31) and
Pedlosky (1982) (p. 180).
- Ekman pumping
In oceanography, a process that is the result of a combination
of Ekman dynamics and horizontal variations
in the wind stress. The resulting convergence and divergence of
the surface flow will force vertical water motion called
Ekman pumping or suction, respectively.
- El Nino/Southern Oscillation
El Nino refers to a massive warming off the coastal waters of Peru
and Ecuador and the Southern Oscillation to the related atmospheric
component of this phenomenon, often abbreviated as ENSO.
The ocean warming covers a band from 10 N to 10 S and extends
more than 90 of longitude. Typically, the warming starts late in
the boreal spring or summer and builds to a peak at the end of the
year, with the event usually over by the following summer.
It is a quasi-periodic phenomenon with global consequences in the
form of flooding, droughts, and other phenomena. See
Cane (1986), Enfield (1989),
Neelin et al. (1994), Philander (1990), and
Philander and Rasmusson (1985).
A member of the class Elasmobranchii.
A class of marine vertebrates of the subphylum
Vertebrata of the
These are primitive fishes whose endoskeleton is composed of
cartilage and that have both paired fins and a lower jaw.
Examples include sharks, rays, and skates.
See Kuhl (1972).
The Electra Doppler Radar is an airborne Doppler weather radar
instrument designed to provide
high-resolution measurements of the air motion and rainfall
characteristics of very large storms that
are frequently too large or too remote to be adequately
observed by ground-based radars. It is commonly known as
ELDORA in the United States and as ASTRAIA (Analyese Stereoscopic
par Impulsions Aeroporte) in France, and more fully known as
See Hildebrand et al. (1996).
Abbreviation for European Lake Drilling Program, a project whose
aim is to recover specific annually laminated lake sediments
to study the paleoenvironmental conditions of Europe.
ELDP Web site.
- elevation angle
See local elevation angle.
Acronym for European Land-Ocean Interaction Studies.
The Scandinavian name given to the Kansan
Acronym for the European Multi-Sensor Airborne Campaign.
EMAC Web site.
In meteorology, a diagram of the temperature (T) versus the
natural log of the pressure (ln p). The energy available
for vertical convection is calculated by measuring the
areas between the prevailing lapse rate
and the adiabatics followed by and ascending parcel on an
See Byers (1944).
Eastern Mediterranean Deep Water.
1. Acronym for Equatorial Mesoscale EXperiment, an experiment
conducted over the tropical oceanic area north of Australia
in Jan.-Feb. 1987. It explored the vertical air motions
and other kinematic properties of tropical mesocale
convective-cloud systems by direct aircraft penetration.
The objectives of EMEX were to document, as intensively
and directly as possible, the vertical profile of vertical
velocity and other kinematic structures over the ocean near
the equator with the most up-to-date instrumentation
available and to investigate the physical mechanisms responsible
for the convective and stratiform components of the
observed cloud systems.
See Webster and Houze Jr. (1991).
2. Acronym for Equatorial Monsoon Experiment.
The ratio of the emittance from a body to that of a black body
emitter at the same temperature, i.e. the degree to which a real
body approaches a black body radiator.
The rate at which radiation is emitted from a unit area.
- empirical orthogonal function
EOF analysis provides a convenient method for studying the spatial
and temporal variability of long time series of data over large
areas. It splits the temporal variance of the data into orthogonal
spatial patterns called empirical eigenvectors. A set of orthogonal
spatial modes can be identified such that, when ordered, each
successive eigenvector explains the maximum amount possible of the
remaining variance in the data, and each eigenvector pattern is
associated with a series of time coefficients that describe the
time evolution of the particular spatial mode.
The modes are orthogonal, which means that any two modes are
uncorrelated in space and time and, as such, no one mode is related
to any other. See Peixoto and Oort (1992)
and Preisendorfer (1988).
See Eurafrican Mediterranean Water.