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Monday 11 November 2013

TSUNAMI


TSUNAMIS

KILLER WAVES






Photo: Great Nicobar Island after tsunami






tsunami is a series of ocean waves that sends surges of water, sometimes reaching heights of over 100 feet (30.5 meters), onto land. These walls of water can cause widespread destruction when they crash ashore.
These awe-inspiring waves are typically caused by large, underseaearthquakes at tectonic plate boundaries. When the ocean floor at a plate boundary rises or falls suddenly it displaces the water above it and launches the rolling waves that will become a tsunami.
Most tsunamis, about 80 percent, happen within the Pacific Ocean’s “Ring of Fire,” a geologically active area where tectonic shifts make volcanoes and earthquakes common.
Tsunamis may also be caused by underwater landslides or volcanic eruptions. They may even be launched, as they frequently were in Earth’s ancient past, by the impact of a large meteorite plunging into an ocean.
Tsunamis race across the sea at up to 500 miles (805 kilometers) an hour—about as fast as a jet airplane. At that pace they can cross the entire expanse of the Pacific Ocean in less than a day. And their long wavelengths mean they lose very little energy along the way.
In deep ocean, tsunami waves may appear only a foot or so high. But as they approach shoreline and enter shallower water they slow down and begin to grow in energy and height. The tops of the waves move faster than their bottoms do, which causes them to rise precipitously.
A tsunami’s trough, the low point beneath the wave’s crest, often reaches shore first. When it does, it produces a vacuum effect that sucks coastal water seaward and exposes harbor and sea floors. This retreating of sea water is an important warning sign of a tsunami, because the wave’s crest and its enormous volume of water typically hit shore five minutes or so later. Recognizing this phenomenon can save lives.
A tsunami is usually composed of a series of waves, called a wave train, so its destructive force may be compounded as successive waves reach shore. People experiencing a tsunami should remember that the danger may not have passed with the first wave and should await official word that it is safe to return to vulnerable locations.
Some tsunamis do not appear on shore as massive breaking waves but instead resemble a quickly surging tide that inundates coastal areas.
The best defense against any tsunami is early warning that allows people to seek higher ground. The Pacific Tsunami Warning System, a coalition of 26 nations headquartered in Hawaii, maintains a web of seismic equipment and water level gauges to identify tsunamis at sea. Similar systems are proposed to protect coastal areas worldwide.





TSUNAMI IN JAPAN




RESULTS OFF THE TSUNAMI


Source: National Geographic

Name: Chen Carmen
Class: 7 Kappa

Typhoon Haiyan: Philippines destruction 'absolute bedlam'

The head of the Red Cross in the Philippines has described the devastation caused by Typhoon Haiyan as "absolute bedlam".

Officials estimate up to 10,000 people have died in Tacloban city and elsewhere. Hundreds of thousands of people are displaced.

Rescue efforts are being hindered by damage to roads and airports.

The storm has now made landfall in north Vietnam, near the Chinese border, but has weakened to a tropical storm.

One of the most powerful storms on record to make landfall, Haiyan - named "Yolanda" by Filipino authorities - barrelled into the eastern coastal provinces of Leyte and Samar on Friday.

It then headed west, sweeping through six central Philippine islands.

Destroyed houses hit by Typhoon Haiyan in the town of Guiuan in Eastern Samar province, central Philippines on 11 November 2013

Almost 630,000 people have been reported displaced.

 More than nine million people have been affected in the Philippines. Many are now struggling to survive without food, shelter or clean drinking water.

  • The exposed easterly town of Guiuan, Samar province - population 40,000 - is said to be largely destroyed

  • Tacloban, Leyte province, was largely flattened by a massive storm surge and scores of corpses are piled by the roadside, leaving a stench in the air as they rot, say correspondents. Hundreds of people have gathered at the airport desperate for food and water, others trying to get a flight out

  • Disaster worker Dennis Chong told the BBC that assessments in the far north of Cebu province had shown some towns had suffered "80-90% damage"

  • Baco, a city of 35,000 in Oriental Mindoro province, was 80% under water, the UN said

  • For more informations, click here > http://bbc.in/1dXd7IA

    Jamie Tay
    7 Kappa :)


















    Phillippines Earthquake

    The quake happened at 00:12 on a national holiday. It struck below the island of Bohol.

    DEATHS
    • At least 93 people have been reported after a magnitude 7.2 earthquake hit the central Philippines.
    • There were also deaths in the province of Cebu.
    • 69 of the 93 people were confirmed dead from Bohol.
    • 15 people were killed in Cebu.
    • Many others are treated for injuries.
    • At least 5 people from died when part of a fishing port collapsed in Cebu.


    RESCUE
    • Search and rescue operations are being conducted, with rescuers finding themselves hampered by damaged roads.

    REPONSE
    • " There was a panic when the quake happened and there was a rush towards the exit."
    •  Officials from Bohol and Cebu have declared a state of emergency in their respective provinces.
    •  Strongest tremor felt in the area for the last 23 years.
    The collapsed facade of the San Pedro y San Pablo church in Loboc town, Bohol province
    7.2 earthquake

    Residents walk along huge cracks in a road after an earthquake struck Bohol province, central Philippines, October 15, 2013.
    Huge crack in the centre of a road in Bohol.


    Workers use a crane to lift up concrete block that fell on a car after buildings collapsed during an earthquake in Cebu city, central Philippines, 15 October 2013
    Damage in the neighbouring Cebu.

    Hospital patients are evacuated after an earthquake struck Cebu city, in central Philippines 15 October 2013
    Evacuation

    Rescuers shift through the rubble to recover an unidentified man at a fish port in Pasil, Cebu, central Philippines, 15 October 2013
    Part of the port building collapsed


    If you are busy doing geography work and have no time to read the news then just scroll through this. I took it from the BCC online news website. Enjoy!!

    Name: Soh Jing Wen
    Class: 7 Kappa

    Nile River

    • Longest river in the world
    • Stretches throughout Africa
    • Drainage basin covers 10% of Africa
    • Source is Lake Victoria


    TRIBUTARIES

    Atbara river

    •  Located below the confluence of Blue Nile
    • Source: north of Lake Tana
    • Only flows when there is rain in Ethiopia which dries very fast

    Blue Nile

    • 1400 kilometres long
    • Provides 59% of the water in River Nile
    • Source: Ethiopia
    • Largest tributary

    Yellow Nile

    • Former tributary connecting the Ouaddai Highlands of eastern Chad to the Nile river valley
    • Remains are known as Wadi Howar

    Hope you learn something!!

    Name: Soh Jing Wen
    Class: 7 Kappa

     


    Employment structure in Uk







                                                                                                                                                     Arif


    Parts of river





                                                                                                                                                       Arif

    Thursday 3 October 2013

    Prevailing Winds

    Prevailing Winds => Directions where the wind is likely to come

    Prevailing Winds in Britain from the South bring warm weather, whilst winds from the North brings cold weather.

    Tropical Maritime
    Source => Atlantic ocean/ Bermuda Triangle

    Characteristics
    1)Large amount of moisture
    2)Bring warm weather to UK

    Tropical Continental
    Source=>Africa (deserts)

    Characteristics
    1)The wind that blows to Southwest England does not bring normal rain, it brings orange rain (carries dust from Sahara desert) 

    Polar Continental (cold and dry) 
    Source=> Scandinavia/Russia

    The distance from source to UK is short therefore not much rainfall is brought. 

    Winters=>Very cold, brings snow
    Summer=>Warm, stable condition

    Arctic Maritime 
    Source=> Atlantic Ocean

    Winters and Springs=> Cold condition

    Duration of agriculture of the land that this winds blow to=> Very short

    Main activities of the land that this winds blow to=> Tourism, cattle ranching

    Polar Maritime
    Source=> Canada/ Greenland

    Characteristics
    1)The most common air mass to reach UK
    2) Brings cold conditions through the year 
    3)Brings more rain
    4) Forms clouds
    5) Showers during winter



    Prevailing winds of UK 


    Source: Google images, geo notes  

    Chow Jo Yi 7 Kappa