Properties of water Flashcards
What is the water molecule made up of?
A covalent bond of two hydrogen and one oxygen
As ice what state are molecular structures in?
Water molecules are tightly bound to each other
As liquid what state are molecular bonds in?
Molecules are less tightly bound but closer together.
Why does ice float?
Ice has more inter-molecular space.
Ice is less dense than water, thus will float.
When does water density decrease?
When the water temperature rises
What does the heat buffering capacity of water do?
Reduces temperature fluctuations in aquatic environments
How much solar radiation is absorbed by ocean waters and land?
47%
How deep does solar energy penetrate in water?
Most heat is absorbed in the top 2m.
Solar energy is absorbed rapidly so it doesn’t penetrate far.
What is convection?
The movement of hotter less dense water to rise, and colder more dense water to sink. ⬆️⬇️
What is advection?
The transfer of heat or matter by the flow of fluid // heat is transferred by currents in ocean ⬅️➡️
What is turbulent mixing?
Fluid flow where it undergoes irregular fluctuations or mixing. 🔃
What is salinity?
Total amount of solid material dissolved in water.
- This includes dissolved gases.
- Doesn’t include dissolved organic substances.
What determines the density of water?
Heating and salinity
What drives water movement?
Water movement is indirectly driven by temperature through density changes.
What is thermocline?
The transition layer between the warmer mixed water at the surface and the cooler deeper water below.
What does insulation of surface waters cause?
Evaporation and Back Radiation
Cooling, density changes, convection currents
What disturbs thermoclines?
Wind generation
Turbulent mixing
What is an important consequence of thermocline formation?
Stratification
What does stratification mean?
Thé division of a water column into layers with different densities.
What can stratification do to a water column?
Suppress mixing
Depletes nutrients in surface layers
Create barriers to movement
