Downwelling occurs in areas such as in the subpolar gyre of the North Atlantic where several surface currents meet, where
cold waters meet warmer waters
, such as along the outermost boundary of the Southern Ocean where cold Antarctic water sinks below warmer South Pacific and South Atlantic waters
Which region would you expect to find downwelling occurring?
Downwelling reduces biological productivity and transports heat, dissolved materials, and surface waters rich in dissolved oxygen to greater depths. This occurs
along the west coast of Alaska in the eastern boundary region of the Gulf of Alaska gyre
(driven by winds in the Aleutian low).
What causes downwelling quizlet?
What does downwelling cause?
Causes water to be forced down
. … Surface water is transported off-shore and replaced by deeper water, that moves inshore and is upwelled. Reverse occurs when the wind is oriented in the opposite direction.
Under which conditions is upwelling likely to occur?
Conditions are optimal for upwelling along the coast
when winds blow along the shore. Winds blowing across the ocean surface push water away
. Water then rises up from beneath the surface to replace the water that was pushed away. This process is known as “upwelling.”
What direction do ocean currents in the South Pacific move under El Nino conditions?
Winds moving westward in the South Pacific drive ocean currents
toward the west
; deep water rises to replace water driven westward.
Where does downwelling occur in the ocean?
Locations. Downwelling occurs in areas such as in the
subpolar gyre of the North Atlantic where several surface currents meet
, where cold waters meet warmer waters, such as along the outermost boundary of the Southern Ocean where cold Antarctic water sinks below warmer South Pacific and South Atlantic waters.
Which of the following ocean currents would you expect to be densest?
According to the graph,
Antarctic Bottom Water
is the densest, Antarctic Intermediate Water is the least dense, and North Atlantic Deep Water has a density between the others.
Where does downwelling occur quizlet?
Downwelling occurs
along the coastline of Antarctica
.
What causes upwelling and downwelling quizlet?
Winds blowing from the north
cause upwelling along the continents’ eastern coasts in the Southern Hemisphere. Upwelling and downwelling also occur in the open ocean where winds cause surface waters to diverge (move away) from a region (causing upwelling) or to converge toward some region (causing downwelling).
What three ways do the stirring movements associated with upwelling and downwelling benefit the ocean?
Upwelling and downwelling describe mass movements of the ocean, which affect both surface and deep currents. These movements are essential in stirring the ocean,
delivering oxygen to depth, distributing heat, and bringing nutrients to the surface.
Which force creates upwelling or downwelling in the coastal ocean?
In winter,
winds blow from the south to the north
, resulting in downwelling. During the summer, winds blow from the north to the south, and water moves offshore, resulting in upwelling along the coast.
Are subtropical gyres downwelling or upwelling?
It is more of a slow drift of cooler water that rarely exceeds 10 centimetres (about 4 inches) per second. Associated with these currents is
coastal upwelling
that results from offshore Ekman transport. The subtropical gyres are anticyclonic circulation features.
How does downwelling affect productivity?
Downwelling is where surface water is forced downwards, where it may deliver oxygen to deeper water.
Downwelling leads to reduced productivity
, as it extends the depth of the nutrient-limited layer. … As the surface waters diverge, deeper water must be brought to the surface to replace it, creating upwelling zones.
Which direction do ocean currents in the South Pacific move under El Niño conditions quizlet?
-Winds moving westward in the South Pacific drive ocean currents toward
the west
; deep water rises to replace water driven westward.
What climate condition occurs during El Nino?
An El Niño condition occurs when
surface water in the equatorial Pacific becomes warmer than average and east winds blow weaker than normal
. The opposite condition is called La Niña. During this phase of ENSO, the water is cooler than normal and the east winds are stronger. El Niños typically occur every 3 to 5 years.
What is the effect of the presence of El Nino in the western Pacific Ocean?
During an El Niño event,
sea surface temperatures over the central and eastern Pacific become warmer than normal
. The normal easterly trade winds weaken and sometimes, the winds will switch and blow from the west to the east!
What causes downwelling in the oceans?
What causes downwelling? Downwelling occurs
when the water on the surface of the sea becomes denser than the water beneath it and so it sinks
. Seawater gets denser when it gets colder or saltier. … And once it gets to high latitudes, the water becomes even more saline as ice forms and further concentrates sea salts.
In which ocean does the Labrador Current Flow?
The Labrador Current is a cold current in
the North Atlantic Ocean
which flows from the Arctic Ocean south along the coast of Labrador and passes around Newfoundland, continuing south along the east coast of Canada near Nova Scotia.
Which conditions in the ocean promote high productivity?
The proximity to land and its nutrient sources,
the interception of sinking organic matter by the shallow seafloor
, and the propensity for coastal upwelling all result in highly productive ecosystems.
What is the meaning of downwelling?
a downward current of surface water in the ocean
, usually caused by differences in the density of seawater.
Where are the two densest patches of seawater located?
The densest ocean water is formed in two primary locations near the poles, where the water is very cold and highly saline as a result of ice formation. The densest deep water mass is formed in the
Weddell Sea of Antarctica
, and becomes the Antarctic Bottom Water (AABW).
How does salinity affect ocean water density?
High salinity makes water denser
. This is because there is more salt packed into the water. High temperature makes water less dense. As water gets warmer, its molecules spread out, so it becomes less dense.
Does downwelling occur in Antarctica?
One prominent current in Fig 1 is the Antarctic circumpolar current. South of Australia and New Zealand, this current is
convergent
, producing downwelling. The Antarctic Convergence zone is a well-defined line where northwards cold surface water from Antarctica meets warmer waters from the oceans of lower latitude.
Why is downwelling important?
Why is downwelling important?
It brings down oxygen that animals in deeper water need
. Why is upwelling important? It brings up nutrients that algae and other animals need that live close to the surface.
What is the most abundant gas found in ocean water?
Gas Percent of volume or pressure Partial pressure, Torr | Nitrogen 78.03 593.02 | Oxygen 20.99 159.52 | Argon 0.94 7.144 | Carbon 0.03 0.228 |
---|
How are ocean surface currents organized?
Surface currents are organized by
distribution of continents, gravity, friction, and the Coriolis Effect
.
What is the great ocean conveyor belt?
The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity. The great ocean conveyor
moves water around the globe
. … Cold, salty water is dense and sinks to the bottom of the ocean while warm water is less dense and remains on the surface.
Why do upwelling and downwelling make animal life possible at all depths of the ocean?
Because of upwelling nutrients,
krill are abundant enough to feed the largest animals on earth
, baleen whales, as well as myriad penguins, seals, and seabirds. … The importance of upwelling to surface organisms is matched by the need of sea bottom life for downwelling, or the sinking of surface water.
Does El Nino cause downwelling?
Upwelling
: the transport of deeper water to shallow levels. One oceanic process altered during an El Niño year is upwelling, which is the rising of deeper colder water to shallower depths.
What is true about upwelling and downwelling currents quizlet?
Upwelling currents are
caused when surface water is blown away by the wind and deeper water rises
(moves) to replace the water that has blown away. Downwelling currents are the opposite of upwelling currents and occur when the wind blows towards a coastline, causing the water on the surface to sink.
What is the Coriolis effect and what causes it?
The Coriolis effect is a
natural event in which objects seem to get deflected while traveling around and above Earth
. The planet Earth is constantly rotating, or spinning, from west to east. Every 24 hours, it completes a full rotation. This rotation causes the Coriolis effect.
Why is the movement of ocean water called thermohaline circulation?
Water with a high salinity is also denser than less saline water.
Deep ocean currents are driven by differences in the water density, which is controlled by temperature (thermo) and salinity (haline)
, hence the name “thermohaline circulation”.
What is downwelling radiation?
Downwelling short-wave radiation at the surface has a component due to the direct solar beam,
and a diffuse component scattered from atmospheric constituents and reflected from clouds
. Upwelling short-wave radiation comes from reflection at the surface.
How does thermohaline circulation differ from surface wind driven circulation?
thermohaline circulation
Wind-driven circulation, which is strongest in the surface layer of the ocean, is the more vigorous of the two and is configured as large gyres that dominate an ocean region. In contrast, thermohaline circulation is
much slower
, with a typical speed of 1 centimetre (0.4…
Which of the following two factors cause Geostrophic circulation within a gyre?
Which of the following two factors cause geostrophic circulation within a gyre?
temperature and pressure
.
Is upwelling caused by the Coriolis effect?
Upwelling is a process
in which currents bring deep, cold water to the surface of the ocean
. … This is known as the Coriolis effect and is largely responsible for upwelling in coastal regions. The Coriolis effect also causes upwelling in the open ocean near the Equator.
Which ocean basin has circumpolar circulation?
The
Antarctic
Circumpolar Current (ACC)—a clockwise circulation around the Southern Ocean composed of strong jet filaments—approximately marks the boundary between waters dominated by polar processes and those of the warmer subantarctic.
Which ocean currents is associated with Indian ocean?
The Indian Ocean gyre is composed of two major currents:
the South Equatorial Current
, and the West Australian Current.
What drives thermohaline circulation?
These deep-ocean currents are driven by
differences in the water’s density
, which is controlled by temperature (thermo) and salinity (haline). This process is known as thermohaline circulation. … This initiates the deep-ocean currents driving the global conveyer belt.
Which process causes downwelling off the coast of Antarctica quizlet?
The Coriolis effect causes surface waters to move at an angle relative to the wind direction.
Ekman transport
can result in both upwelling and downwelling.
What direction do ocean currents in the South Pacific move under El Nino conditions?
Winds moving westward in the South Pacific drive ocean currents
toward the west
; deep water rises to replace water driven westward.
Why is the Sargasso Sea called a sea?
The Sargasso Sea is
named for the Sargassum seaweed that creates its unique ecosystem
. This Sea has been called a golden floating rainforest.