THE EARTH SOLAR SYSTEM :Planets-MECURY - SUN-VENUS - STARS ( BALLS OF GAS )-EARTH-MARS-JUPITER-SATURN-URANUS-NEPTUNE-PLUTO ( DWARF PLANET )
ABOUT THE EARTH-EARTH IS A SPHERE SHAPED PLANET .-IT IS THE 3RD PLANET FROM THE SUN.- THE DISTANCE FROM THE EARTH TO THE SUN IS 150 MILLION KILOMETERS.- IT IS THE 5TH LARGEST PLANET IN THE SOLAR SYSTEM- The surface of the Earth is 70% water and 30% land masses .- There are 7 continents - There are 5 oceans 1)Europe 1) Pacific ocean 2) Asia 2) Indian ocean 3) North America 3) Southern ocean 4) South America 4)Atlantic ocean 5)Africa 5) Arctic ocean 6) Australia 7)Antarctica
LIFE ON EARTHATMOSPHERE - Oxygen ( 21%) , Nitrogen (78%), Carbon Dioxide (0.03%), Water Vapour (1%).Plants flourish Animals flourish FoodTemperature – Not too cold and Not too hot ideal for lifeCarbon dioxide keeps average temperature bearable to 15 Degree Celsius Glaciers/Ice =2%97% of the Water on Earth – sea water3% of the water on Earth – Fresh water Rivers = 1%
Temperatures oLowest temperature on Earth : -20 C oHighest temperature on Earth : 47 C oLowest temperature in the solar system : -500 C oHighest temperature in the solar system : 400 C
Earth’s Movements Earth has 2 movements – Rotation about its AXIS Revolution around the SunThe Earth is rotating while it is revolving .- The movement of the Earth involves a rotating Earth , revolving round the Sun . * It takes 24 hours / 1 day to complete 1 rotationThe Earth rotates from the West to the East .= Rotation causes day and night * Earth moves along the Orbit (Path the Earth follows) It takes 365.25 days to complete 1 revolution¼ x 4 = 1 extra day365+1=366 days ( leap year ) : every 4 years ( February 29 )
Earth’s TiltEarth tilts at 66.5 degrees ( has a major impact ): tilts towards the sun = gets more heat & sunlight : tilts away from the sun = gets less heat & sunlight As Earth moves around the sun , different parts of the Earth will tilt towards the sun at the different times of the year. E.g. ) China (Northern hemisphere ) Australia ( Southern hemisphere)Causing the 4 seasons
Day in Summer : sun’s ray directly shining on Earth North Pole – 24 hours of sunlightDay in Winter : no sun’s ray - Winter solstice - North Pole – 24 hours of darknessTwice a year : Equal hours of sunlight and darkness - Equinox - Spring and Autumn
STEPS TO DRAWING EARTH’S REVOLUTIONSTEPS1) Draw the sun FOR PICTURE PLEASE REFER2) Draw 4 positions of the Earth ( smaller than the sun) TO THE NEXT SLIDE.3) Directions of revolution ( West to East )4) Draw the tilted axis (to show northern & southern hemisphere )5) Draw equator ( to show hemispheres also )6) Label diagram7) Label months EXTRAS !!!!!!!!8) Divide Earth : summer and winter Different countries9) Label solstices and equinox experience seasons in different times of the year . Longest day in Singapore is always Day when there summer or facing towards the sun are equal hours winter of daylight
HUMAN’S POSITIVE AND NEGATIVE IMPACTS ON THE ENVIRONMENT(INTERRELATIONSHIP) POSITIVE NEGATIVECloud seeding DeforestationRe-planting IMPACT … LEADS TO – SOIL EROSION
Introducing the Physical EnvironmentNatural vegetation , such as trees , takes in carbon dioxidefrom the surrounding air and gives out oxygen throughthe process of photosynthesis . The trees also take inwater that has fallen onto Earth’s surface when it rainsand that flows into the river and lakes the moisture givenout by the trees, evaporate and becomes water vapour inthe air .The trees grow in soil that is from broken rocksand the trees take in nutrients that are from decayednatural vegetation . These are some ways thecomponents of the physical environment areinterrelated. When something happens to onecomponent , the others will be affected too.
CLIMATE & NATURAL VEGETATION INTERRELATIONSHIP• Rainfall & temperature determines type of natural vegetation found in an area• Water(rainfall) & heat(temperature) affect plant growth• Forests thrive in places with high rainfall (>1500mm annual rainfall)• Grasslands thrive in places with moderate rainfall (< 750mm annual rainfall)• Desert vegetation are found in places with low rainfall (<250mm annual rainfall )
Acid Rain • Burning of fossil fuels releases sulphates and nitrates into air • Sulphates and nitrates mix with water vapor in air and form sulphuric acid and nitric acid
Contamination of lakes• Lakes and ponds can become so contaminated that no life can live in them and we will have no food to eat .
Deforestation • Population growth leads to the loss of natural habitats • Cut down trees to build new homes • Loss of biodiversity • Loss of oxygen producers and CO2 eliminators
CFC’s• Carbon-Flouro-Carbons in aerosols were leaking into the atmosphere and eating away the ozone layer .
Pollution• Water Pollution – Oil Spills – Gasoline spills Gets into drinking water
Global Warming• Increase in CO2• Increase in greenhouse effect• Increase in global temperatures
HOW THE !KUNG BUSHMEN ADAPT TO THE PHYSICAL ENVIRONMENTThe !kung bushmen live in the Kalahari Desert in Africa . They only take what they need not what they want . They live in huts that are easily washed or blown away .The hunter-gatherer will hunt for food and collect berries and some plants to eat . For water bottles , the !kung bushmen use ostrich eggs .The !kung bushmen live closely to the physical environment unlike Singaporeans who destroy the physical environment . Transportation is also an issue in the Kalahari desert , they walk as far as 3 kilometers with an empty stomach to help the villagers to find food ( THEY WALK BAREFOOTED ON THE ROCKY GROUNDS AND UP AND DOWN HILLS).
LONGITUDE AND LATITUDE- Measured in degrees- Imaginary lines encircling THE EARTH- All latitude lines are parallel to each other- All longitude lines are parallel to each other- Latitude lines : EW ( HORIZONTAL)- Longitude lines: NS (VERTICAL )- CALCULATE latitudes BEFORE longitudes• How To remember this … A comes before O in the alphabet
LONGITUDE-Lines that encircle in NS direction- Cuts through the north and south pole- Increases in value as you move away from the Prime meridian / Greenwich meridian ( 0-180 degrees E,0- 180 degrees W): same line- -reference lines are the Prime meridian / Greenwich meridianInternational date line Place in England*separates 2 consecutive days called Greenwich*gain +(1) day if you travel from EW
LATITUDE- Lines that encircle in EW direction- Increases value as you move away from the equator (0-90 degrees NORTH ,0-90 degrees SOUTH)- 90 degrees N : north pole 90 degrees is- 90 degrees S : south pole the MAX- Equator – 0 degrees , divides Earth into 2 hemispheres (northern and southern hemispheres)*major latitudes -Arctic circle (66.5 degrees N) -Tropic of cancer (23.5 degrees N) -Tropic of Capricorn (23.5 degrees S) -Antarctic circle (66.5 degrees S)
Special Latitudes• Tropic of Cancer (23.5degrees N)• Tropic of Capricorn (23.5degrees S)• North Pole (90 degrees N)• South Pole (90degrees degrees S)• Equator ( 0 degrees )• Arctic circle (66.5 degrees N)• Antarctic circle (66.5 degrees S)SINGAPORE :1 degrees 22’0” North (Latitude)103 degrees 48’ East (Longitude)
MAPS*different maps have different features using symbols , colours and scales .*LEGENDS- help us locate a placeTYPES OF MAPS-1) Political Maps- countries , cities (NO physical features)2) Climate Maps- weather , temperature , rainfall3) Economic Maps/Resource Maps- economic activities , type of natural resources .4) Road Maps – roads , highways , streets , train tracks5) Physical Maps – physical features ( e.g.-: hills , rivers..)6) Topographical Maps- HUMAN environment features+shape and elevation/ height of physical features –REPRESENTED BY CONTOUR LINES
Reading maps• The darker the colour in the climate maps , the more the rainfall….• Mountain ranges , deserts …... are all reflected in the physical maps .• Topographical maps have IMAGINARY lines measuring the height of some physical features called CONTOURS or contour lines .• Atlases are books that contain many different kind of maps – of different countries , cities , neighbourhood , world and more …
THE EARTH’S LANDFORM -Mount Elbert : in Colorado , highest peak in therocky mountain- Andres : world’s longest continental mountain range- Mount Everest: In Himalayas , Nepal . Tallest mountain ever- Mount Fugi : 3000m in height , dormant volcano*Volcanoes ARE mountains BUT a mountain maynot be a volcano.
HillsGentler slopesLess than 600 m in heighte.g :loess hills
MountainsSteep slopesMore than 600m in heighte.g: Himalayas ,Alps , the Rockies ,Andes
PlateauPlateau : “flat”- “plate” in FrenchRaised flat surface landformcollapsed mountainsolder than mountainsbounded on one or more sides by steep slopese.g : Tibetan plateau , mount Conner’s plateau
PlainsExtensive piece of flat landUsually lower than land around theme.g : Tone Sap in Cambodia
ValleyLong and narrow stretch or land found betweenhigher ground .E.G : V-shaped valley in Nepal
HOW LANDFORMS AFFECT PEOPLEPositive Effects: Negative Effects:Natural resources – Natural Barriers – Hydro-electric power , Mountains limit movement ,Geothermal energy , mining , human barriers to construction of networkssettlement and agricultural activities and poor accessibility.Academic value -: Technological Hindrance- Knowing how Earth changes over Steep terrain difficult to use.time. Difficult on farms difficult to farm Natural Hazards- Avalanches “snow slides” , landslides , volcanic eruptions.
VOLCANOES AND HOW THEY AFFECT HUMANS• Positive impacts • Negative impactsRocks and Minerals EruptionsGeothermal Energy Ash CloudsFertile soils Lava FlowTourist attraction
COREIt is the innermost part of the Earth.It is 2900 km THICK and is made out mainly ofiron and nickelIt is also subject to very high temperatures (about 5000 Degrees Celsius )
MANTLEIt lies above the core and it makes up nearly80% of the Earth’s volume . It is about 2900 kmthick.It is mostly solid except for its upper layers ,which consists of molten rocks or MAGMA
CRUSTIt is the outermost layer of the Earth , the surface on whichwe are living .It floats on the DENSER mantle and it is about 60 km thick .It is broken up into pieces called CRUSTAL PLATES.There are 2 kinds of crustal plates , namely the CONTINENTALPLATE and the OCEANIC PLATE .The continental plate is lighter than the oceanic plate
CRUSTAL PLATESTHE ARROWS SHOW THE DIRECTIONS IN WHICH THE PLATES MOVE . The place wheretwo PLATES MEET is called the PLATE BOUNDARY .
CRUSTAL MOVEMENTS THE CONVECTION CURRENTS WITHIN THE EARTH’S CRUST . The Earth’s crustal plates float on the mantle . Extreme heat from the interior of the Earth’s crust causes convection currents to be generated . These internal forces cause crustal movements on the Earth’s surface .
PARTS OF A VOLCANOCone : It is build up by successive layers of cooled and solidified lava , mixedwith ash and rock fragments .Crater : It is the opening at the top of the volcano through which lava , rockfragments , gases and ash are ejected .Lava : It refers to molten rocks that have been erupted onto the Earth’s surfacePipe : It is the channel that joins the magma chamber to the top of the volcanoand through which molten rock flows .Vent : It is the opening in the Earth’s crust which allows magma to rise to thesurface .Magma chamber : It is an underground cavity which contains molten rocks.
VULCANICITY AND VOLCANOESVulcanicity is the process which molten materialsare forced onto the Earth’s surface .A volcano is a mountain formed by the successivelayers of cooled and solidified lava that eruptedfrom a VENT .Volcanoes are normally formed along plateboundaries where plates either collide or spreadapart .
VOLCANIC ERUPTIONSVOLCANIC ERUPTIONS occur when hot magma , driven by itsgases , rises up from the Earth’s mantle and breaks throughthe Earth’s surface.As it rises , the molten rock pushes and fractures whatever gets in theway, causing earthquakes.Enormous amounts of ash and rock fragments can beejected hundreds of metres into the atmosphere because of intenseheat and pressure . A violent eruption is often characterised.It is characterised by an enormous ejection of ash and rock fragmentsinto the atmosphere followed by gushing torrents of red hot lava flowingdown the slopes of the volcano .
Crustal Plates move towards each other When the convection currents within themagma pulls two crustal plates towardseach other , the plates collide . The lighterplate will float above the denser plate asthey collide INDIAN PLATE EURASIAN (Moving North PLATE (Moving and East) South )
Crustal Plates move away from each other Plates can also move away from eachother when the heat within the magmadrives the plates apart.
FRACTURE ZOESIn some cases , two plates slide horizontallypast one another . This forms a fracturezone when a large crack called a faultdevelops . The most famous example is the SanAndreas Fault in California , western U.S.A.
FOLD AND FOLDING MOUNTAINSWhen two crustal plates collide , thetremendous forces created by the collisioncauses some rock layers to be folded andwarped , forming mountains . This process iscalled FOLDING . The Andes (Aconcagua ,6960m) , the Rocky mountain (Mt Elbert ,4399m) and the Himalayas (Mt Everest ,8848 m) are the world’s three LONGESTmountain ranges . THEY ARE ALL FORMEDBY FOLDING. THE HIMALAYAS IN ASIA IS STILL GROWING TALLER EVERY YEAR .
THE LOUDEST SOUND IN THE WORLD – THE ERUPTION OF KRAKATAUIn 1883 , Krakatau erupted , producing the loudest sound everhistorically recorded by the human beings . The eruption was heard asfar away as the Philippines , Australia and even Rodriguez Island inMauritius 4653 km away. The island erupted with a loud of 100megatons of TNT ( Trinitrotoluene , an explosive ), which is similar to thepower of 21548 atom bombs . During the eruption , a lot of volcanic materials were ejected andthese materials settled over and area of 777000 KM(2) .(about 1000times the SIZE of SINGAPORE)! The eruption ejected huge amounts ofash (fine volcanic materials ) which blocked out the sunlight andplunged Jakarta into complete darkness. The catastrophic eruption was caused when sea water entered themagma chambers of Krakatau . The superheated steam generated bythis mixture built tremendous pressure within the volcano , resulting in amassive explosion . The force was so great that the volcano collapsed acaldera that was 6km in diameter . Two-thirds of the original Krakatauwas destroyed.
CLASSIFICATION OF VOLCANOES- Can be classified in 3 types : active , dormant andextinct . It is a volcano that is currently erupting or is likely to erupt It is a volcano that It is a volcano soon . that is not is presently expected to inactive but may erupt again erupt in the future
WEATHER , CLIMATE AND PEOPLEPOSITIVE IMPACTS1)Harness energy from sun (solar energy )Solar panels on roofs can covert solar energyinto electricity used for heating and supplyinghot water to homes .
2) Harness energy from windWind power can help to generate electricity that does not pollute the environment .: Commonly found in countries that receive anabundance of strong winds (eg; China , USA ,Germany ….)“wind turbines”
3) FarmingFavorable weather conditions ensure good quality of crops grown .(eg; carrots need short frost period in order to besweet . )Certain climate allows more than one crop to be grown ( MORE VARIETY OF CROPS )(eg; tropical climate ) Singapore can grow a lot
4) TourismWeather and climate can attract tourists to visit a particular country .(eg ; tourists from colder regions may flock toMaldives to sun tan and swim at the tropical beaches)
NEGATIVE IMPACTS1) Extreme water issues ( floods and droughts) heavy and prolonged rain can cause rivers tooverflow their banks and flood the surroundingareas lives lost , damages buildings andtransportation networks Prolonged and abnormally dry periods can issuerivers and reservoirs to dry up drought cropfailure famine (widespread food scarcity )
RAINFALLRain is a type of precipitation.Snow is also a type of precipitation.How is rainfall measured?Rainfall is measured using a rain gauge.Rainfall is usually measured in millimetres(mm).
PARTS OF A RAIN GAUGE- FUNNEL- CYLINDER- COLLECTING BOTTLE- OUTER CYLINDER
Where should the rain gauge be placed?• In an open area / field – So that nothing will block the rain from being collected in the rain gauge.
Where should the rain gauge be placed?• A rain gauge should not be place near trees. – So that excess water collected from the leaves will not drip into the rain gauge making reading inaccurate . OR – The tree prevent water from being collected in the rain gauge make the reading inaccurate.
Where should the rain gauge be placed?• A rain gauge should not be place near buildings. – So that excess water from the rooftop will not drip into the rain gauge making reading inaccurate . – The building could also radiate heat causing the water collected to evaporate.
Where should the rain gauge be placed?• It should be partially buried in the ground – to prevent it from being topple.
Where should the rain gauge be placed?• It should be placed 30 cm above the ground – to prevent rain splash entering the rain gauge making the reading inaccurate.
Climograph• It is a graph that shows the monthly precipitation and temperature conditions for a selected place.• Precipitation is shown by the bar graph.• A line graph shows temperature.
• What is the rainfall for the month of July?• Which month experiences the highest temperature?• What is the temperature range for the whole year?• What is the average precipitation from May to July?
SIX’S THERMOMETERA Minimum and MaximumThermometer ( Six’s Thermometer)Minimum thermometer Maximum thermometerContains alcohol , mercury and a metal indexMeasure the minimum temperatureTemperature rises> mercury expandsWhy is alcohol used?mercury pushes the index upTemperature falls > mercury contracts and stays in placeHow do you reset t he thermometer?
STEVENSON’S SCREEN1 .) White in colorreflects heat2.) Raised above groundshelters the instruments form the heat radiating from the ground3.)Face north and southDo not get the direct heat from the sun4.) Placed in open fieldDoes not have interruptions
Oblique Photographs• Photographs that are taken at a high point taken at an angle. – These can be taken from aircraft such as a plane or hot air balloon. – Can also be taken from a cliff looking down at an oblique angle• Using this angle we are able to discover more of the features in the background
Vertical Photographs• Usually taken from a specially equipped plane with a camera mounted underneath – pointing straight down. • The maximum tilt of the camera is 3° degrees, If it goes over this angle it will be classified as an oblique photograph• These photos will show less detail but more area of the environment
Satellite Imagery• A satellite is an object that orbits a planet. These are able to capture larger areas of the Earth’s Surface. – Gathering information from satellites is called Remote Sensing.