Objectives for Hydrologic Cycle, Shorelines and Oceans (2)

1. Be able to reproduce the hydrologic cycle and the formula for the hydrologic budget of a watershed.

*(going to be a fill in the blank)

*see image

What percent of the Earth’s surface is covered by ocean, and what percent of the total water on Earth is contained in the oceans?

1. 71% of the Earth’s surface is covered by ocean

   1. 60% of northern hemisphere

   2. 80% if southern hemisphere

2. 97% of water on Earth is contained in the oceans

3. Average depth of 3.8 km

   1. Largest reservoir of freshwater on Earth is stored in glaciers

   2. Largest useable source of freshwater on Earth is groundwater

What percent of ocean water is dissolved salt?

3.5%

1. Which is most dense: a) salty or fresh water/ b) warm or cold water?

1. Saltier is denser

2. Colder is denser

1. What is the chemical reaction when CO2 dissolves in water, and what happens if this chemistry reacts with Ca or Mg?

1. CO₂ + H₂O -> H₂CO₃

2. H₂CO₃ -> H + HCO₃

3. Mg or Ca + HCO₃ -> H + Ca/MgCO₃

   1. Bicarbonate Chemistry System

   2. Hydrogen ions dissociate from the carbonic acid, to give bicarbonate, and then a carbonate ion, which then reacts with a calcium cation to form calcium carbonate

1. What two common gasses and one common mineral dissolve better in cold water?

1. CO₂

2. O₂

3. CaCO₃  (Calcite)

What drives surface currents, and what drives deep ocean currents?

1. Wind drives surface currents

2. Downwelling of dense water (cold and salty) drives deep currents (density differences)

1. What effects do these currents have on the heat distribution of the planet, and what would happen if these currents slowed down or were not as efficient at this process?

1. They move heat from the equator to the poles

2. Keeps equator cooler and poles warmer

What causes tides? When do you get the highest and lowest amplitude tides, and what are they called, and what astronomical configuration gives rise to each?

1. Gravitational pull of the Sun and Moon causes tides

2. Highest amplitude tides have higher highs and lower lows. They are called spring tides. Astronomical configuration is Earth, Moon, Sun in a straight line.

3. Low amplitude tides have smaller highs and less lows. Called Neep Tides. Destructive interference. Astronomical configuration is the right angle of moon, earth, and sun.

1. What effect do tides have on the Earth’s rotation, and the Moon’s revolution around and distance from the Earth?

1. Tides cause the Earth's rotation to slow down

2. Moon’s revolution is speeding up and it is getting farther from Earth

Know what factors affect the size and power of waves.

1. Wind speed

   1. Faster wind makes bigger waves.

2. Wind duration

   1. The longer the wind blows, the larger the waves will be.

3. Fetch

   1. The farther over the water the wind blows, the larger the waves will be.

On a picture showing a series of waves, be able to label the following features, crest, trough, wavelength (L), wave base.

(maybe a short response?)

 Know what happens to a wave as it approaches a shoreline.

1. Wave base touches bottom, and causes drag

2. Velocity drops

3. Wavelength decreases

4. Wave height increases

5. Waves break as they hit shoreline

 What is the difference between a primary and secondary coastline?

1. Primary coastline is on a plate boundary (west coast). Also called active coastlines.

   1. Sea Stacks, sea arches, sea cliffs

   2. Secondary Coastline is not on a plate boundary. Also called passive coastlines. (East Coast, Gulf of Mexico)

      1. Gentle sloping land leads to the ocean.

Understand the concept of wave refraction and its importance to coastal erosion.

1. Wave refraction is the bending of waves

2. It straightens out the shoreline

 Know the difference between longshore current and beach drift, and know if they go in the same or opposite directions.

1. Longshore current is the movement of the water and it is a current that runs parallel to the beach

2. Beach drift is the movement of sand and runs parallel to the beach

3. They move in the same direction

How do humans attempt to control beach erosion?

1. Add Groins

2. Add Jetties

3. Add Breakwater

4. Add Sand

 Between what two latitudes can hurricanes form?

1. Between 5 and 20 degrees latitude North and South of the Equator

1. What two factors compete against each other regarding hurricane formation in a warming world, and what prediction results from this?

1. Warming waters and upper atmosphere windsheer 

2. More upper atmosphere windsheer decreases number of hurricanes

3. Warmer waters increase number of hurricanes

4. We do not know if global warming will increase the number of hurricanes or not

1. Historically, what has been the main case of damage when a hurricane hits shore, and is it getting better or worse?

1. Storm Surge

2. Hurricanes will be bigger and stronger 

3. Therefore, storm surge will be getting worse

1. What are three ways to change global sea level, and which, if any, are we concerned about today?

1. Melting of glacial ice (concern)

2. Thermal expansion of sea-water (concern)

3. Increased rate of sea-floor spreading (not a concern)