Sunday, February 27, 2011

Year 10: Coastal Management Vocabulary List

Constructive waves- A low-frequency that spills the wave and a wavelength get longer and makes low crest which can run the slope of the beach.


corrosion- is a  wearing away of small/fine particles of rock on a  by a sandpapering action called abrasion

deposition- is the geological process by which material is added to a landform.
destructive waves- A plunging wave, with a short wavelength, a high frequency and a high crest, which breaks so that the water crashes downwards from the wave crest and erodes the beach

erosion- The group of natural processes, including weathering, dissolution, abrasion, corrosion, and transportation.


fetch-often called the fetch length, it means the length of water which can give wind blown.
foredune- A dune ridge built up behind a coastline. Generally higher and more extensive than a beachridge.
hydraulic action- is a form of erosion caused by the force of moving water currents rushing into a crack in the rock face. 
longshore drift-  is the movement of sediments, usually sand, along a coast parallel to the shoreline.
refractionRefraction is the change in direction of a wave due to a change in its speed. 
surf and swash zoneSwash (uprush and backwash), in geography, is the water that washes up on shore after an incoming wave has broken. 
vegetation succession- The gradual evolution of a series of plants within a given area. This series of communities occurs in a roughly predictable order.
wave height- The height of the wave.
wavelength- The length of the wave.
7.1
Breakwaters- Breakwaters are structures constructed on coasts as part of coastal defence or to protect an anchorage from the effects of weather and longshore drift. 
faecal coliform- A fecal coliform is a facultatively-anaerobic, rod-shaped, gram-negative, non-sporulating bacterium.
silting - Silt is granular material of a grain size between sand and clay derived from soil or rock. 
tidal flushing – The action of saltwater entering an estuary twice a day during the high tides.
7.2
ground swell - A broad deep undulation of the ocean, often caused by a distant storm or an earthquake.
plunging waves - A plunging wave occurs when the ocean floor is steep or has sudden depth changes, such as from a reef or sandbar. 
spilling waves - Spilling waves occur when the crest tumbles down the front or face. Spilling waves will usually form as the tide recedes leaving less water on banks on which waves are breaking
surging waves - A rise above normal water level on the open coast due only to the action of wind stress on the water surface

wind swell - In fluid dynamics, wind waves or, more precisely, wind-generated waves are surface waves that occur on the free surface of oceans, seas, lakes

7.3
aeolian - ?
spinifex - Spinifex is a genus of perennial coastal grasses.


7.4
dredging - Dredging is an excavation activity or operation usually carried out at least partly underwater,
erosion-accretion cycle- 
groynes - A groyne is an active structure extending from shore into sea, most often perpendicularly or slightly obliquely to the shoreline.
revegetation - Revegetation is the process of replanting and rebuilding the soil of disturbed land. This may be a natural process produced by plant colonization
sea walls - Seawalls or Sea Walls is a term used to describe an embankment that prevents the erosion of a shoreline by water.
7.7
environmental impact study – The study of the environmental impacts
impact assessment - Impact assessment is the process of identifying the future consequences of a current or proposed action.
7.8
bitou bush -  Bitou bush was once used to stabilise sand dunes, but has now become a significant weed in coastal areas.
marram grass -  A type of grass that grows and survives in the desert, sand.
noxious weed -  A noxious weed is an invasive species of a plant that has been designated by county, state or provincial.
7.9
anemometer - An anemometer is a device for measuring wind speed, and is a common weather station instrument.
hygrometer - A Hygrometer is an instrument used for measuring the moisture content in the environmental air, or humidity. 



Sunday, February 20, 2011

The Science of Big Waves

Previewing


1. Where do ocean waves come from? What gets them started?


Answer: Waves are generated by wind out on the ocean. On the ocean, with nothing to stop them and much deeper water under them, these ripples continue to grow as the wind continues to push them. There are heaps of variables which will affect the shape and size of waves. But to answer where waves come from is really to answer where wind comes from, and the answer is the Sun.


2. What do you think a surfer should know about waves before they try and ride a wave while surfing?


Answer: Stay away from heavy shore break beaches, reef breaks, point breaks. You want a mellow sandy bottom spot with slow peeling mushy waves, and not to many people out. You want to learn to surf, not get beat up and held down and thrashed around. Do your homework and this can make the difference in having a good first experience or a bad one.


Question for the Video


1. Observe all the waves that you see and describe how they form and break. Use as many words found in the segment for you descriptions.


Answer:There are two factors that waves breaks. First, The depth of the wave where it is breaking. Every waves breaks on a spot of the sand where the depth of the wave is half as deep as the wave is tall. For example.: if the wave is depth is 1 meter deep, then the height of the wave will be 2 metres. Second, The speed of the wave. If the wave is travelling at a high speed, then the barrel of the wave will shape like a lying-down almond.


2. Describe how waves are formed, how they originate, and how they are measured?


Answer: Also, waves can be formed by gravity under the water level and the light. They can measure the waves by looking at the wavelength. 


3. What is a maverick wave and what is special about the way it is formed?


Answer:When the sloping ramp leads up to the surface under the wave break. The presence of this ramp slows the propagation of the wave over it. The wave over the deep water troughs on each side of the ramp continues at full speed forming two angles in the wavefront centered over each of the boundaries between the ramp and the two troughs


4. How is energy stored and transferred during wave?


Answer:All the energy stored at the surface to half the wavelength and transfer to the front side of the waves.


5. List any kind of advice given by the surfers about how to survive these “big waves.”


Answer: Catch the wave before the wave falls down.



7.6 The Tweed River Entrance Sand Bypassing Project

1 Why did it become necessary to extend the Tweed River breakwaters?


Answer: It was necessary to extend the tweed river breakwaters due to further sand build-up. Around that time, the longshore drift became longterm effects..


2 What impact would the construction of the breakwaters have had on the replenishment of sand to the Gold Coast beaches after severe storm erosion?


Answer: It would be better to replenish the sand to Gold coast beaches after severe storm erosion like sand from beaches being naturally supplied of sand.


3 Why did the Tweed River become unsafe to shipping? Explain the natural process that caused sandbars to form over the mouth of the Tweed River.


Answer: The sandbats were forming across the river mouth in the Tweed river and the tweed river became dangerous place.


4 Why was the dredging of the Tweed River and the associated beach nourishment program only a short-term solution to coastal management of the area?


Answer:  It was only a short-term solution to coastal management as it was a expensive solution and one which would need to occur continually in order to maintain the sand supply to the beaches and 
safety of the river entrances.


5 Describe the way the TRESBP replaces the natural process of longshore drift.


Answer: the sand was pumping from where it is accumulated on the Southern side of the Tweed river which it aims to replicate the natural process of longshore drift.


8 Look at the aerial photographs in 7.28. Describe the changes that have occurred to the mouth of the Tweed River since 1962.


Answer: The Mouth of the Tweed River has a fair amount of sand on it but not enough to become a major hazard but in 1969 a large amount of sand has appeared on the right side of the beach. However the amount of sand hasn't built up obviously in 1994.


9 Using the topographic map in 7.25 on page 164, estimate the length of the breakwater along the Tweed River entrance in 1962 and in 1994. *


Answer: There was only 100 - 200m in 1962 while it has been extended to 250m in 1994.

Monday, February 14, 2011

Monday Feb 14 Year 10 (period 1 + 4): Mapping Skills 7.5 Coastal Management on the Gold Coast

7 Express the scale of the map as a statement: One centimetre on the map represents kilometres on the ground.
Answer: 1 cm represents 0.25km


8 What is the contour interval of the map?
Answer: the contour interval of the map is 10cm.


9.Calculate the following.
a) the width of the mouth of the Tweed Rive
Answer: 250m


b) the length of the breakwater on the southern side of the Tweed River
Answer: 375m


c) the length of the jetty extending into the ocean from the sand pumping station in AR 5483
Answer: 500m


d) the distance along the beach from the lookout at Greenmount Hill to the Rainbow Bay surf club
Answer: 350m


e) the time it would take you to walk along the beach from the Rainbow Bay surf club to the Coolangatta Beach surf club if you were walking at a speed of 5 kilometres per hour.
Answer: 16.5 minutes


10 Which is higher, the lighthouse at Point Danger or the lookout on Kirra Hill?
Answer: Lighthouse at Point Danger


11 What is the aspect of the slope where the electricity substation is located in AR 5283?
Answer: Downslope


12 What is the approximate height of the small electricity substation in AR 5283?
Answer: 80m


13 Name the human features location at the following grid references.
a) 532824
Answer: Island
b) 536823
Answer: Terranora inlet
c) 541844
Answer: light house
d) 513834
Answer: highway
e)528819
Answer: Caravan Park
f) 532828
Answer: wharf


14 Name the natural features located at the following grid references.
a) 524818
Answer: Boyds island
b) 537822
Answer: island
c) 514844
Answer: Kirra Beach
d) 521833
Answer: Mount Murraba
e) 544817
Answer: Island
f) 544839
Answer: River


15 Refer to 7.24 and the topographic map. Give the grid reference of the lookout that the photographer was standing at when the photograph was taken.
Answer: 526845


16 What is the density of buildings in AR 5483?
Answer: Low density


17 Which area has the greatest density of buildings per square kilometre—AR 5281 or 5282? Give a reason for your answer.
Answer: AR 5282 has a greater density of buildings per a square kilometer as the AR doesn't cover the Terranora creek like AR 5281.


18 Estimate the bearing of the following features from the water tank on the top of Mount Murraba
a) the groyne at Kirra Point
Answer: 30 degrees
b) the mouth of the Tweed River
Answer: 75 degrees
c) Boyds Island
Answer: 166 degrees
d) Snapper Rocks *
Answer: 55 degrees 



7.3 Geographical Processes Shaping the Coastal Environment

1. For the first image use Google maps to find a beach that is of similar shape. Capture it and label the picture with the information in the diagram 7.7. 




2. Find pictures for each of these coastal features in the next TWO pictures (do at least 10) (7.13 + 7.9). Copy them to your blog post and label them. (you don't have to do 'beach'). Post to blog.


Tombolo


Coastal lagoon


Offshore sandbar


barrier dune system


sand dune


sand spit


bay


blow hole


head land


natural bridge


wave cut platform


sea stacks


sea cave


3. Find a picture of a Headland with a Wave-Cut Platform and label it with the information in 7.8. Post to blog
4. Find a beach (any beach will work) and use all the labels from the longshore drift diagram below to annotate it. Post to blog.





Wednesday, February 9, 2011

Year 10 Geography 7.1

 1. Describe how the settlement pattern of Australia is related to issues in the coastal environment?
Answer: Population growth of coastal areas normally occurs, because of the current Australian trend for people to move from large cities to smaller towns making the population increase too much.. River entrances are still silting up as a result of human impacts.
2. Why is the sustainable development of the coastline the aim of coastal management strategies?
Answer: The development of coastlines is the purpose because then society is still developing the coast while keeping natural processes.
3.What trend has been labelled 'sea change'?
Answer: Population growth of coastal areas occurs due to the current Australian trend for people to move    from large cities to smaller towns making it overpopulated. "Sea change' is the name applied to this process.
 4. Describe one government response to 'sea change'.
Answer: Some towns have imposed  a population ceiling to prevent the overdeveloping of the coast.
 5. Select four of the geographical issues facing the coastal environment presented in this unit. For each issue identify the human actions that cause the issue.
Answer: Pollution has been caused because of sewage outfalls in the water; silting of river entrances caused by boats passing through them; native vegetation die out because of overrunning introduced plants; natural cycles interrupted because of urbanisation on coastlines
6. What role do geographers play in developing management solutions to issues in coastal environments? 
Answer: Geographers play an essential role in determining the suitability of developments and ensuring the sustainable use of coastline