ENV100 Blue Planet Keywords

Mixed layer

upper part of the ocean, direct contact with the atmosphere, nearly uniform properties, boundary layer

Coriolis effect

Moving objects are deflected to the left due to the earths rotation

Ekman Transport

1. Surface layer moves by force of the wind

2. Layer gains momentum and as energy is transferred down layers, they move further left

3. Friction consumes all energy at depth of 100m

Upwelling

1. Surface winds push surface water away from an area

2. Deficit of water at the coast

3. Deep, cold, nutrient-rich water rises from beneath surface to replace water pushed away

Downwelling

Occurs when surface waters converge, pushing surface water downwards

Subtropical Gyres

Big circular movements of ocean currents occurring in subtropics, close to equator

Western boundary currents

Return warm water towards the poles, warm water from equator transported into cooler regions, radiates heat warming, regulating

Gulf Stream

Narrow western boundary current moving warm water from tropics to pole

Thermohaline Circulation

Process that drives deep ocean currents in regards to the waters density, controlled by temperature and salinity

AMOC

Atlantic Meridional Overturning Circulation, system of ocean currents circulating water within the Atlantic Ocean

Ocean Bathymetry

Refers to ocean’s depth relative to sea level, depths and shapes of underwater terrain

Equilibrium Theory

The moons gravity tugs on Earth, distorting the shape. As primary bulge is drawn towards the moon the secondary bulge is left behind because of the weaker gravitational pull

Diurnal Inequality

Two high tides and two low tides of unequal sizes in the same day, influenced by the position of the moon

Conjunction and Opposition

Changing position of the moon and sun and monthly variation in tidal range, sun and moon are in line with each other, pulling in the same direction = combined gravitational effect = spring tides

Quadrature

Changing position of the moon and sun and monthly variation in tidal range, sun and moon are not in line, pulling in different direction, 90 degrees out of phase

Apogee & Perigee

Once a month where the moon and the earth are closest = apogee and furtherest = perigee from each other

Tidal Range

Height of the tide minus height of successive

Aucklands Tides

Average = 1.5m high, range = 2.7m, semi diurnal

Ocean Currents

Masses of ocean water that flow from one place to another

Tides

The alternate rising and falling of the surface of the ocean