Water and Ocean structure - Lecture 2 Flashcards
What are the characteristics of a water molecule?
Composed of 1 oxygen and 2 hydrogen atoms. A polar molecule. Hydrogen bonds hold water molecules together.
What is Cohesion?
The ability of water molecules to stick to each other, this creates surface tension.
What is Adhesion?
The tendency of water molecules to stick to other substances.
Define: Heat Capacity.
A measure of the heat (Calories) required to raise the temp of 1g of a substance by 1 degree Centigrade.
Define: Heat.
The energy produced by random vibrations of atoms of molecules.
Define: Temperature.
An objects response to heat.
What is water’s heat capacity? and what does this mean?
4.18J. Water resists changing temp when heat is added or removed, this is due to the strong H bonds.
What do ocean surface conditions depend on?
- Heavy Rainfall in equatorial regions “freshens” the ocean. - Much latent heat is used to evaporate water in tropics and is released when vapour is carried towards the poles and reprecipitated.
What does the principle of constant proportions imply about the chemical makeup of the ocean?
Although the salinity(total amount of dissolved solids) may cary between sea water in different locations, the ratio of major salts in the water is constant.
What is the ration of water:other components in sea water?
965.6g : 34.4g
What are the percent of gasses dissolved in sea water?
Nitrogen - 48% Oxygen - 36% Carbon Dioxide - 15% (60x more than in the atmosphere - 0.04%)
Why do these gas concentrations vary with depth?
Photosynthetic activity of marine plants dries these concentrations. In the ares near the surface carbon dioxide is being used and oxygen released. In the aphotic water where sunlight is minimal carbon dioxide builds up as photosynthesis cannot occur.
How are the zones of the ocean categorised?
The zones of the ocean are categorised by temperatures and salinity.
What are the three vertical zones of the ocean?
Surface zone(2%) - upper layer, least dense water. Pycnocline(18%) - zone in which density increase with depth. Deep zone(80%) - little change in density.
What are the different types of pycnocline?
Thermocline - The rapid increase in the pycnocline due to a decrease in temperature with depth. Halocline - The rapid increase in the pycncoline due to vertical cariations in salinity.
Which colour light does ocean water transmit the most efficiently?
Blue light is transmitted the most efficiently.
