Thursday, May 5, 2011

Emperor Penguins



Habitat....
Gathered in huge groups sort of like colonies, emperor penguins live off the coast of Antarctica. Unlike other penguins, the emperor penguin do not migrate to warmer climates during the winter. This would be would of the toughest penguins because they survive in harsh  weather conditions and breed during that time as well. Emperor penguins usually use the coastal ice cliffs for shelter. They can generally spend most of their life without ever having to come on the land.


Predation & Prey...
Emperor penguins are very good swimmers and they are very strong making them good predators. They are alos great divers, diving as deep as 1750 ft holding their breath for about 18 minutes. Emperor penguins usually feed on fish, krill, and squid. And larger marine mammals prey on them and sharks as well during the spring.


Reproduction...
emperor-penguin_8Honestly I think the breeding system is cute. The emperor penguins breed during the winter months so that by the time it gets warmer the chicks will be mature to leave mom and dad. Thats smart because the weather conditions are much better. The emperor penguin reproduces internally, and early winter is when they start mating. Around May the female penguin lays one egg and passes it onto the father immediately after and he will be in charge of the egg for 3-4 months with out food. But of course he fills up his belly for the long days ahead. All of the males huddle together to keep warm, while the females store up food for their young. When it is time for the chick to be born, at the beginning of September the female returns from the ocean to find her baby. The chicks can recognize their parents from their call. The parents take turns going back and forth getting food for the newborn until they old enough to get on their own and venture out.
Adaptations...
The emperor penguins has 4 layers of skin to protect them from such cold Antarctic weather. Even though they wobble while walking their feet, to speed up the process they flop on their stomachs and slide using their wings to push themselves along the ice. As mentioned the males huddled together, each taking turns so each of them in a group can feel the warmth in the interior to help them survive.
Conservation....
The emperor penguin is not listed as endangered but there is a concern because scientist say that by the way the climate keeps changing, human distrubance and global warming can decling breeding. Melting is a big factor for breeding locations as well.
Classification
Aptenodytes forsteri

Interesting Facts
  • The emperor penguin is the tallest and heaviest of all known penguins. They reach up to a weigh anywhere from 22 to 45kg.
  • emperor-penguin_2Even though it considered a bird and has wings, highest feather density of any bird species, it cannot fly.
  • The emperor penguins can start mating when they are 4 years of age.
  • Emperor penguins have a life span of about 20 years.Emperor Penguins, Weddell Sea, Antarctica

Monday, November 22, 2010

THIEVES Project

Title: Coastal Dynamics
Heading: Long shore Drift
Introduction: 
How does long shore drift move material along the coastline?
  • Long-shore drift is helped but long shore currents, from waves approaching the beach at an angle and wind pushing water on shore.When the waves move on shore, they stir up sediment.
Every 1st Sentence: One of the most significant forces shaping the coast is long shore drift, which is the net transport of sediments along the coast by a long-shore current.

Visuals and Vocabulary:
long shore current- a current parallel to shore caused by waves approaching the beach at an angle.
long shore drift- the movement of sediment and materials along the coast, caused by a long shore current.



Title: Coastal Dynamics
Heading: Beach Dynamics
Introduction: 
Where does sand come from? 
  • Most sand comes from erosion, which results from streams and rivers that carry it onto the ocean. Sand may come from local rocks, and can also come from portions of coral reef.
A beach is composed of what three sections?
  • Its composed of the foreshore, back shore, and offshore.
What factors affect the shape and appearance of a beach? 
  • Interacting factors include the grain size of beach sediments, wave energy, and the degree of beach slope.
What is a coastal cell?
  • A coastal cell is a local region of material transport mechanisms that, when combined, form an area with no net sand gain or loss.
Every 1st Sentence: Long-shore drift explains one of the major ways that sand moves along the coast.

Visuals and Vocabulary:
bioerosion- erosion caused by species eating coral polyps and excreting sand as digestive waste, the parrotfish is one species that performs this process. 
forshore- the region of a beach from the high tide mark to the low tide mark.
backshore- the region of a beach rarely touched by seawater, including dunes or grasses all the way to "non-beach" ground.
lowtide terrance- the flat portion of the foreshore of a beach where the waves break.
offshore- the beach area beyond low-tide terrace; it includes a long shore trough and shallow sandbar that both parallel the shore.
longshore trough- a slightly deeper area in the offshore section of a beach, running parallel to shore.
coastal cell.



Title: Coastal Dynamics
Heading: Large-Scale Sand Features
Introduction:
What causes a spit to form?
  •  A spit forms when a long shore current turns a beach corner into the relatively calm water of a bay. The current slows and cannot carry as much sediment. Sand settles out of the water, forming the spit.
What causes tombolos to form?
  •  Tombolos are spits that extend between two islands or from an island to the mainland. When there is a slower water flow, sand doesn't move that much. The sand eventually accumulates and forms two spits that eventually grow together into a tombolo.
Why are barrier islands temporary coastal features?
  • Barrier islands are rarely the same each day, they gradually move inland as the sea erodes the coast. High winds and storm surges can alter barrier islands within a short period. That's why most people living on barrier islands risk vulnerable situations during hurricanes.
What five features make up a "typical" barrier island? 
  • An ocean beach, sand dunes, a barrier flat, a salt marsh, and a lagoon.
What are difference between river-dominated, tide-dominated, and wave-dominated deltas?
  • River dominated  deltas have strong rivers, mild waves, and tidal action. They also tend to have a triangle shape, an example is the Mississippi River delta. Tide-dominated deltas occur in areas with strong tidal changes. They usual form tidal channels from ridge sediments. and an example is the Essex River in Massachusetts. Wave-dominated deltas have significant wave energy that redistributes river sediments. An example is the Senegal delta in west Africa.
Every 1st Sentence: Sand movement and accumulation form significant coastal features.

Visuals and Vocabulary:
spit- a length of accumulated sand attached to land at one end, pointing in the direction of the long shore drift.
bay mouth barrier- a sand barrier created by a spit accumulating so much sediment near the edge of a larger water body.
tombolo- a spit that extends between two islands or between an island and the mainland.
barrier flat- a broad, relatively level area behind the dunes of a barrier island, with vegetation ranging from grasses to woodlands.
salt marsh- an intertidal grassland that is usually biologically diverse and productive.
lagoon- an area of shallow water separated from the ocean by a barrier island or other obstruction.
river-dominated deltas- a delta with a strong river and mild wave and tidal action.
tide-dominated deltas- a delta in an area with strong tides that redistributes accumulating sediments.
wave-dominated deltas- a delta in an area with high wave energy that redistributes accumulating sediments as dunes and spits.


End of Reading:
True/False
1. There are two basic types of dominated deltas 
2. A beach is composed of three sections: offshore, foreshore, and backshore.
 
Multiple Choice
3. Factors that affect the shape and appearance of a beach are: 
       a) grain size of beach sediments, wave energy, and the degree of beach slope.
       b) wave energy, and long shore current
4. Barrier islands are temporary coastal features because:
       a) they hardly move at a rapid rate
       b) they are very good especially during hurricanes
       c) high winds and storm surges can altar them in a short period


Fill-in 
5. A _________ delta has the characteristic of a triangle shape.
6. The _________ is that part between the high-tide mark and the low-tide mark.


Summary:

There are many dynamic changes in the world but, the constant change takes place on our coasts. The beach is a common area that moves constantly. Dynamic marine factors that affect this movement are: the wind, the change in sea levels, waves, erosion and many other factors. This section show how sediment and other materials are transported along the coast by longshore currents and longshore drift.  It goes into detail about what a beach is composed of and how its appearance can change through energy created by high wave action and backwash. This section also shows significant coastal features and how these features affect the water flow and shape our environment. 


Current Research

The impact of climatic change on coastal landsystems: What lies in the future?


The impact of climatic change on coastal landsystems: What lies in the future?
Global warming and its associated climate changes will cause worldwide sea level to rise in this century and beyond, and although dramatic sea-level change has been common throughout the Quaternary, and even in the Holocene, it will impact in a major way on coastal landsystems and the populations that inhabit the coast. The aim of this section is to provide a summary of the likely effects of sea-level rise on the various types of coast and then undertake a detailed case study to examine the effects in more detail.
Currently there are several calculations of the extent of future sea-level rise, but most predict a rise of 10–15 cm by 2030, accelerating to 30–80 cm by 2100. Such rises will cause major coastal changes around the world. Eventually all of the world’s coastlines will be submerging coastlines, even in areas that are stil emerging after the effects of the last glacial, like the Gulf of Bothnia. There will be extensive submergence of low-lying coastal areas and current intertidal areas will be no more. On rocky coastlines sea-level rise will just raise the high- and low-tide levels, although the amount of marine erosion is likely to increase. As sea-level rises, coasts that are now stable will be increasingly eroded, and this erosion will accelerate on coastlines that are already receding. This will be exacerbated by more-frequent and higher-energy storms than are now apparent, which will cause surges further inland than they have appeared in the past. In particular, coasts already suffering storm surges due to hurricanes, like the Gulf and Atlantic coasts of North America, will have more frequent, persistent and extensive marine flooding.
However, although there will generally be a deepening of near-shore environments, some coasts may receive an increased sediment supply from longshore or river sources, which may maintain or even diminish the near-shore profile as sea level rises. Wave energy here will not intensify and there might even be progradation. So predictions are usually speculative when it comes to precise impacts, but nevertheless some generalizations are possible and useful.
The impacts of global warming will also cause a migration of climate zones. Tropical cyclones will become more frequent and severe and will extend to higher latitudes, for example. There will be changes in coastal currents like the El Ni˜no Southern Oscillation (see Chapter 8). Some areas will receive more rainfall, increasing river flooding, which will result in a water-table rise and add to that caused by sea-level rise. These climatic changes will have a major impact on coastal ecosystems and their distribution.