Oceans and Circulation Flashcards
What is the mass of the oceans versus the atmosphere? Consider units.
Ocean Mass = 1.4x10^21 kg
Atmospheric Mass = 5.0x10^18 kg
How many parts per thousand of the ocean consists of salt?
35 parts per thousands
What is meant by specific heat capacity?
The amount of energy required to cause a solid, liquid or gases temperature to increase by 1 degrees Celsius. It is usually expressed per kilogram of the given state.
What is the specific heat capacity of oceans compared to atmosphere compared to rock? Consider units.
Oceans = 4.2 kJ kg^-1 K^-1 Atmosphere = 1.0 kJ Kg^-1 K^-1 Rock = 0.79 kJ Kg^-1 K^-1
What is heat energy capacity?
The amount of energy stored within a body (regardless of mass - we just want to know how much energy it can hold)
How do you calculate heat energy capacity, why? What is the unit?
Mass (kg^+1) X Specific Heat Capacity (kJ Kg^-1 K^-1). The answer, we take the mass unit (kg) out because of indices therefore the answer is expressed as kilojoules per kelvin (kJ K^-1)
What is the heat energy capacity for oceans? In other words how much energy is required to cause it to warm one degree Celsius.
Mass (1.4x10^21 kg) x Specific Heat Capacity (4.2 kJ kg^-1 K^-1) = 5.9x10^21 kJ
What is the heat energy capacity for atmosphere? In other words how much energy is required to cause it to warm one degree Celsius?
Mass (5.0x10^18kg) x Specific Heat Capacity (1.0 kJ kg^-1 K^-1) = 5.0x10^18 kJ
Which is responsible for transporting the majority of energy from the equator to the poles? Why?
Although the oceans can transport and store more energy they are much slower compared to the atmosphere which therefore allows it to transfer energy at a faster rate and more over a short period of time.
What percentage of the energy trapped by the greenhouse gas layer is absorbed by the oceans? Why? What does this therefore help to mitigate?
90%. This is due to its immense heat capacity. global warming.
Describe and explain the relationship between temperature and density of oceans
The starting point of oceans is ice, an increase in temperature causes them to melt which increases their density, but at point (~5 C) the water starts to become less dense as it gets warmer
Describe the relationship between ocean salinity and density
Perfect linear positive relationship - an increase in salinity leads to a proportionate increase in density.
What has a greater impact upon seawater density at cooler temperatures? Think
Salinity - because at cooler temperatures the gradient of density changes of the oceans is steady
What has a greater impact upon seawater density at higher temperatures (~>15C)?
Temperature - the gradient becomes much steeper compared to salinity changes
Despite the oceans absorbing such a large percentage of the atmospheric radiation, what allows them to conserve their temperature?
Immense Mass and the High Heat Capacity means that it can overpower the only source of this incoming radiation at the surface
What is the major distributor of the changes in density at the surface throughout the rest of the ocean?
Thermohaline (Temperature and Salinity) Circulation
What is the basis of the thermohaline circulation?
Bodies of water flow travel across different oceans and at different depths
What allows the thermohaline circulation to happen?
Variations in salinity concentrations due to differences in the inputs of rainfall and freshwater systems from rivers and ice causes the density of different parts of the ocean to move horizontally, from equator to poles, and vertically
What are the ‘distribution centres’ of the thermohaline circulation?
Antarctic and Arctic
How does the Coriolis force influence thermohaline circulation?
In the Northern hemisphere the currents are diverted to the right of primary direction of travel, in the southern hemisphere they are diverted to the left
How and why does the oceanic circulation pattern contrast to the atmosphere?
Because the oceans are bounded by the continents, instead of continuously diverting to the right and forming a cycle they are largely contained to keep to the equator to poles patterns and kept on track.
What process allows the cooler saline water to reach and mix with the shallower depths of the ocean that are less saline and warmer?
Upwelling
What is upwelling?
Wind travelling in one direction over the ocean will experience friction with it causing the surface of the ocean to be dragged in the same direction as the wind. This then allows the water below the surface to well up and fill the void left by the surface water movement.