The Earth a solid planet surrounded by water
The Earth, a solid planet surrounded by water and gases. Dr. María D. Ortega
The origin of the Earth’s atmosphere What do you not know about the origin of our atmosphere?
Origin of the Earth’s atmosphere 4600 million years ago our planet, the Earth, was an immense sphere of melted materials that spun around a young star, the Sun. As time passed the heaviest materials moved to the centre of the planet and the Earth’s layers formed. Our planet cooled and a solid crust was formed. At this stage many volcanoes released lava and gases from inside of the Earth. These gases formed the original or primitive atmosphere that was mainly made of carbon dioxide, nitrogen, water vapour and other gases such as methane and sulphur dioxide, but there was no free oxygen. This atmosphere was very like the atmospheres of Mars and Venus. As the Earth cooled, water vapour rose and condensed forming clouds and for hundreds of millions years torrential rains filled the Earth’s surface forming the seas, the hydrosphere, which began to dissolve carbon dioxide. Approximately 50 percent of the carbon dioxide was absorbed into the oceans. According with the Miller theory, in these warm seas organic molecules were formed with the atmospheric gases and the energy from the lightning and solar radiation. 3500 million ago the first cells appeared in these warm seas. They were like current bacteria. These ancient bacteria lived on carbon dioxide, expelling oxygen gas as waste. This oxygen changed the primitive atmosphere and formed a new one with a bigger amount of oxygen. The living beings changed our planet forever and instead of being a brown and red dead planet, like Mars and Venus, our Earth is a blue planet full of life. http: //www. youtube. com/watch? v=b. IEv 0 cd_x 4 k
New York Madrid Dublin Singapore What is the town I want to go to? Lima Hong Kong Rome Manila Paris Suva Seville Wellington Berlin Tokyo Rabat London Auckland
1. What is the town I want to go to? Rome 1. Where did the first living beings appear? L: on land R: in water 2. The first living beings were: L: Unicellular R: multicellular 3. CO 2 is used by plants to carry out L: photosynthesis R: respiration 4. The main component of the current atmosphere is: L: oxygen R: nitrogen
2. What is the town I want to go to? Manila 1. The main component of our primitive atmosphere was: L: nitrogen R: carbon dioxide 2. Our current atmosphere is like the atmosphere of Mars and Venus L: False R: True 3. The first cells appeared L: 3500 m. y. a. R: 4600 m. y. a. 4. The oceans were formed with the water released by L: volcanoes and comets R: living beings
3. What is the town I want to go to? Berlin 1. 4600 millions years ago our planet was a L: big sphere of melted rock R: big sphere of dust and gases 2. The primitive atmosphere was formed with the gases released by R: living beings L: volcanoes 3. Venus has a thick atmosphere where the main component is L: oxygen R: carbon dioxide 4. The huge amount of oxygen in the current atmosphere was created by bacteria and plants L: False R: True
The Earth is an interacting system of matter and energy, that as part of its functioning produces phenomena like volcanoes, glaciers, mountain ranges, oceans, and continents. The energy that keeps this system going is on one hand the internal heat (from radioactive decay) that drives plate tectonics, and on the other hand solar energy that maintains ocean and atmosphere circulation and helps to drive erosion. The Earth an interacting system
SOLAR ENERGY Hydrosphere Atmosphere Biosphere Lithosphere GRAVITY AND INTERNAL HEAT
The atmosphere is a layer of gases surrounding our planet and retained by the Earth's gravity. The main components of the atmosphere are: 78%: Nitrogen 21%: Oxygen 1%: Noble gases Carbon dioxide =0, 03% Water vapour = variable This mixture of gases is commonly known as air and it contains also solid particles from forest fires and volcanoes as well as bacteria and pollen grains http: //www. youtube. com/watch? v=1 YAOT 92 wu. D 8
Layers of the atmosphere Scientists have divided the atmosphere in layers according to the way its temperature changes with altitude. • Troposphere. The temperature . . . . • Stratosphere. The temperature. . . . • Mesosphere. The temperature again. . . . • Thermosphere. The temperature again …………… In the Tropopause, Stratopause and Mesopause the temperature ……………………. .
• Troposphere is the atmosphere's • • • lowest and densest layer. It starts from the Earth's surface and reaches up 12 km ( 7 km at the poles and 17 km at the equator). The air rises and falls and here all weather phenomena take place. The upper boundary of this layer is called the tropopause. Stratosphere. In this layer the air doesn’t mix and remains in layers or strata. It contains the ozonosphere, a layer made of ozone (O 3) which protects us from ultraviolet rays from the Sun. This layer reaches 50 km. Mesosphere. It reaches 80 -85 km. In this layer meteors are heated due to friction with air molecules and most of them are disintegrated. Thermosphere. It is also called Ionosphere, because the gases here are ionized due to the absorption of extremely energetic solar radiation. This enables the propagation of the radio waves signals. It reaches up 650 km. The solar wind interacts with the Earth’s magnetic field and produce Polar lights or Aurora http: //www. youtube. com/watch? v=A 8 wwe 3 L 1 v. QI
Troposphere It is the atmosphere's lowest and densest layer. It starts from the Earth's surface and reaches up 12 km ( 7 km at the poles and 17 km at the equator). The air rises and falls and all weather occurs here. The upper boundary of this layer is called the tropopause.
Stratosphere In this layer the air doesn’t mix and remains in layers or strata. It contains the ozonosphere, a layer made of ozone (O 3) which protects us from ultraviolet rays of the Sun. This layer reaches 50 km. .
Mesosphere It reaches 80 -85 km. In this layer meteors are heated due to friction with air molecules and most of them are disintegrated. http: //www. youtube. com/watch? v=Rzm 8 d. Q 5 k. Uq 4 Meteors passing through atmosphere http: //www. youtube. com/watch? v=8 mb. A 606 ZRWI Meteor in Gaudalajara
Barringer crater, Arizona, USA
Thermosphere It is also called Ionosphere, because the gases here are ionized due to the absorption of extremely energetic solar radiation. This enables the propagation of the radio waves signals. It reaches up 650 km. The solar wind interacts with the Earth’s magnetic field and produce Polar lights or Aurora http: //www. youtube. com/watch? v=YJBr. MXSn-h. U Aurora borealis
Exercise. Write the words in the appropriate place: rain, polar lights, meteors disintegration, ultraviolet rays absorption, high energy solar radiation absorption, air stays in strata, air moves up and down, gases are ionized, wind, commercial flights, artificial satellites
Role of the atmosphere in the life of our planet 1. What is the role of some of the gases that form the atmosphere? 2. What is the role of some of the layers of our atmosphere? .
Role of the atmosphere in the life of the planet • Oxygen is needed for respiration by animals and plants. • organic matter+ oxygen carbon dioxide + water + energy Carbon dioxide is taken by land plants and seaweeds to carry out photosynthesis that releases oxygen. light Carbon dioxide + water +mineral salts organic matter + oxygen Chlorophyll • Carbon dioxide and water vapour act as “green house gases” that keep • • earth warm enough to maintain life. Without them our average surface temperature would be - 15º Celsius degrees instead of the current 14º. Water vapour is part of the water cycle that produces precipitation (such as rain and snow). Ozone forms the ozonosphere or ozone layer that protects us against ultraviolet rays. Mesosphere protects us against meteors. Thermosphere protects us against high energetic radiations, such as X rays.
Exercises 1. Which layer of the atmosphere absorbs the ultra violet rays? . . Where is it? . . 2. Why do you need to heat a balloon in order for it to rise? . . . . 3. In which layer are meteors disintegrated? . . 4. In which layer does precipitation takes place? . . 5. Why do living beings need oxygen? . . . 6. Why do plants need to carry out photosynthesis? . . . . . 7. In which layer do man made satellites move? . . 8. What would be the temperature of our planet without atmosphere? . . Why? . . 9. In which layer do commercial flights move? . . . 10. Why is our atmosphere thicker over the Equator than over the Poles? . . . . . . . . . . . . 11. What are the main components of our atmosphere? What is its concentration?
Weather and climate Weather is the day-to-day state of the atmosphere, and its short-term variation (minutes to weeks) in a given place at a given time. Climate is the average weather in a location over a long period of time (al least 30 years).
Measuring weather. Do you remember it? Write the name of the instruments that measure • The air temperature. . . . • The amount of rain that has fallen over a specific time period. . . . • The air pressure. . . . . • The wind speed. . . • The amount of water vapour content in the air or humidity. . . • The direction from which the wind is blowing. . . Thermometer, rain gauge, barometer, anemometer, hygrometer, wind vane
Atmospheric pressure and wind • Atmospheric pressure is a direct result of the weight of the air. • It is highest at the Earth's surface and • decreases with altitude. This is because air at the surface is compressed by the weight of all the air above it. For example, the pressure at the top of the Mont Everest is lower than the pressure in Auckland. • Wind is moving air, it moves from the high pressure regions to the low pressure regions. The greater the pressure difference, the stronger the wind. • All of the energy that reaches the earth comes from the sun, so it is the sun’s energy that produces air movement wind
Lows and highs Regions of rising air are called lows, low pressure regions, depressions or cyclones. Pressure is. . . . in the centre of a cyclone. Winds blow in a …………. direction to the centre of a cyclone. ………. , …………and strong winds often occur in these regions. http: //www. bom. gov. au/l am/Students_Teachers/ pressure. shtml#highpres s Regions of sinking air are called highs, high pressure regions or anticyclones. Pressure is ………in the centre of an anticyclone. Winds blow in an …………direction from the centre of an anticyclone ………… skies and ………. . weather usually occur in these regions highest, fair, anticlockwise , rain, clockwise, clear, lowest, clouds
A weather map The curved blue lines are called isobars. These pass through areas with the same air pressure. When the isobars are close together the winds will be strong. The black arrows show the wind direction. High and low pressure regions do not stay in the same place. They move over the Earth's surface. The purple line with triangles is a cold front. The triangles point in the direction the front is moving
A warm front
Reading a map Look at the map and say what is the forecast for Adelaide. …………………………. . How will be the winds in Adelaide? …………………………. . • http: //www. metservice. com/national/maps-rain-radar/index Look at the map and say what is the forecast for New Zealand? …………………………. In which direction will the wind flow in the Steward Island ……………… in Auckland ………………. . and in Wellington ……………
What are breezes?
Breezes During the day land heats up faster than water. Hot air rises from the land, creating low pressure and cooler air comes in from over the sea, where the pressure is relatively higher. This creates a cool onshore breeze that blows from sea to land. When the sun goes down the land loses heat quickly and become colder than the sea. Now the circulation of air reverses creating an offshore breeze. 23ºC 20ºC 32ºC 15ºC
18 C 17 C 28 C 25 C 26 C
Foehn wind and rain shadow Westerlies Warm and moist air • In the South Island of New Zealand, the Southern Alps intercept the moist air coming off the Tasman Sea (Westerly winds). When the air rises it cools and the water vapour condenses forming clouds. Every year more than 7000 mm of rain and snow fall over the mountain range. When the air crosses the Alps it has lost much of its initial moisture and it sinks and warms (Foehn winds), so the water evaporates and the clouds disappear. On the East (leeward) side of the Alps the yearly rainfall is ten times less than on the West (windward) side and the temperature is much higher too.
Exercise. Odd one out. Circle the odd one out in each group and give reasons for your answer in each case. 1. High pressure, fine weather, air spinning anticlockwise, air rises. ……………………………………………………. 2. Rain weather, air spinning clockwise, low pressure, air sinks. …………………………………………………… 3. Thermometer, barometer, wind vane, compass. …………………………………………………… 4. Highs, lows, wind vane, barometer. ………………………………………………………. . 5. Wind vane, breezes, westerlies, hygrometer. ……………………………………………………. . 6. Isobar, milibars, rain gauge, pressure. ……………………………………………………… 7. Day, lows over the sea, land breeze, highs over the land. ……………………………………………………… 8. . Night, lows over the land, onshore breeze or sea breeze, highs over the sea ………………………………………………………. .
Tropical cyclones tracks 1. Why do most of the tropical cyclones that form in the South Pacific die away before reaching New Zealand? 2. Why all the hurricanes are born near the Equator? 3. Why are the tropical cyclones that affect N. Z. formed in December- May period, rather than at other times of the year?
Hurricanes, typhoons, tropical cyclones Tropical cyclones (Hurricanes in the ……………ocean and Typhoons in the …………. . , near China and Philippines) are large tropical storms with strong ………………. . (more than 90 km per hour) and heavy ……………. . The strong winds and excessive rainfall also produce abnormal ……………in sea levels and ………………. . Hurricanes begin as tropical storms over the ………… waters (over 26ºC) of the Atlantic and Pacific Oceans near the ……………. The relatively peaceful centre of the hurricane is called the ………. In this point the pressure is extremely ………. . , so around it winds move at ………. . between 90 and 250 km per hour and big storms are formed with the warm and ………. . air that rises up from the sea. While the hurricane remains over …………… waters, it continues to pull moisture from the surface and grow in size and force. When a hurricane crosses …………. . or ………. . waters it loses its source of power and its wind gradually slow and the hurricane become just a normal ……………. . Atlantic, Pacific, winds, rain, rises, flooding, warm, equator, eye, low, speeds, moist, warm Land, cooler, storm
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Greenhouse effect and global warming http: //www. yo utube. com/wat ch? v=o. JAb. ATJ Cugs
1. What are the causes of the global warming? 2. What are the consequences? 3. What individuals can do about it? 4. What governments can do about it? .
Causes of global warming • Human use of fossil fuels is the main • • • source of excess greenhouse gases. By driving cars, using electricity from coalfired power plants, or heating our homes with oil or natural gas, we release carbon dioxide and other heat-trapping gases into the atmosphere. Deforestation is another significant source of greenhouse gases, because burning trees releases carbon dioxide to the atmosphere and because fewer trees means less carbon dioxide conversion to organic matter. Agricultural activities such as raising cattle and growing rice release methane that is a very active greenhouse gas. As the concentration of greenhouse gases grows, more heat is trapped in the atmosphere and less escapes back into space, so the Earth’s surface temperature increases leading to global warming.
Consequences of global warming • Global temperatures are expected to • • increase 2 to 5 degrees Celsius by 2050. Rising temperatures will alter global weather patterns. There will be more droughts and heat waves and deserts will expand because the sea temperature is rising too, hurricanes will become more frequent. Polar ice caps and many glaciers will melt and the sea level will rise 50 cm by 2100. Coastal areas and many islands will be flooded and millions of people will have to migrate to higher areas Many species will disappear. Rising temperatures will increase the areas where mosquitoes can breed so more people will be exposed to diseases such as malaria or yellow fever.
Things you can do to reduce global warming 1. Reduce, Reuse, Recycle 2. Use Less Heat and Air Conditioning 3. Change a light bulb 4. Drive less and drive smart 5. Buy Energy-Efficient Products 6. Use Less Hot Water 7. Use the "Off" Switch 8. Plant a tree 9. Encourage Others to do the same
Hydrosphere The hydrosphere is composed of all the water on the earth. This includes the oceans, rivers, lakes, and even the moisture in the air and water inside the ground. http: //www. youtube. com/ watch? v=Bvrz. M-Bav. Dg
3% • 97% of the earth's water is in the oceans and it is salt water. • 3% of the earth’s water is fresh water Ø three-quarters of the fresh water is solid and exists in polar ice and glaciers, Ø so only 1% of the Earth’s water can be used by the land livings beings and humans 97%
Water properties and life • Water is a. . . . with one oxygen atom and two hydrogen atoms. • Water molecules tend to. . . . . each other because they have a • • . . charge in one side and a. . . charge in the other side, and the. . . electrical charges attract Water is the only natural substance that appears as a. . . , . . . and. . . at the normal Earth’s temperature. Water is a superb. . . , meaning that other substances easily. . . . . into it. This allows water to. . . . . nutrients to cells, and carry waste away from them. Water has the unique property of. . . as it freezes. Because water expands becoming. . . . , frozen water, or ice. . . This is very important, because it protects the water underneath, . . it from freezing. Water is the main. . . . . of living beings. negative, positive, liquid, less dense, carry, gas, molecule, dissolve, component, attract, floats, expanding, solvent, opposite, solid, , insolating
The hydrologic cycle is the process, powered by the sun's energy, which moves water between oceans, the sky, and the land.
Exercise. Complete the text with the words from the list. The sun. . . . . oceans and lakes and the water. . . . . As air rises, it cools and the water vapour. . . . into tiny droplets of water over the. . . . particles forming clouds. Air. . . . move water vapour and clouds around the globe and the water. . . to the land as. . . or. . . This is called precipitation. Some water can. . . . . forming streams and rivers that finally reach oceans. Water in the soil can be absorbed by. . . . and is then transferred to the. . . . by a process known as. . . Water from the. . is evaporated into the atmosphere and it can. . . . . into the land form. . . . or aquifers. Groundwater reaches oceans where the whole cycle begins again. evaporates, rain, dust, atmosphere, infiltrate, plants, condenses evapotranspiration, heats, currents, falls, snow, runoff, soil, groundwater,
Label the picture with the words of the list Evaporation, transpiration, condensation, transportation, run off, infiltration Percolation, groundwater, precipitation, river flow
The ocean conveyor belt Oceans absorb, store and redistribute vast amounts of the Sun's heat around the globe. The ocean conveyor belt plays a crucial role in the Earth's climate. So, global climate changes could alter, or even halt, the current as we know it today. http: //w ww. yout ube. com /watch? v =3 ni. R_Kv 4 SM
Where does Auckland’s water come from? Auckland’s water supply is obtained from three different types of sources: dams, rivers and groundwater. Water Treatment In a treatment plant the untreated water or row water is removed unsafe contaminants such as suspended solids, bacteria, algae, minerals, and man-made chemicals pollutants. What is wastewater? It is water that has been used for washing, flushing or in a manufacturing process and so it contains waste products http: //www. aucklandcity. g ovt. nz/council/documents/ networkconsents/default. a sp
Water pollution is the contamination of water of lakes, rivers, oceans and groundwater. The more important humans activities that cause water pollution are: • Domestic wastewater Faeces, urine, household cleaning products, microorganisms • Agricultural activities Pesticides Fertilizers Animal manure: urine and faeces • Industrial activities Solvents Heavy metals
Water Pollution 1. What are three most important causes of 2. 3. 4. 5. water pollution? How can agricultural activities produce water pollution? Why shou. ld you not pour chemical products into the storm water system? Where does the rain water go? Where does the water from the toilet and the shower go?
A solid planet made up of minerals and rocks
Structure of the earth: crust, mantle and core
The crust is the outermost part of the Earth. It comprises the continental crust and the oceanic crust. The crust has a variable thickness (between 10 -70 km), being thicker in the continents than in the ocean basins. The rocks of the oceanic crust are less than 200 million year old and they are mainly dense rocks like basalt. The rocks of the continental crust are older than the oceanic crust, some of them are 3. 800 years old. The continental rocks are less dense and the most abundant rock is granite.
It is about 2900 km thick and it is separated into the upper and lower mantle. Here is where most of the internal heat of the Earth is located. Large convective cells in the mantle circulate heat and may drive plate tectonic processes. The mantle
The core is divided into two layers, the liquid outer core and the solid inner core. The outer core is 2300 km thick and it is composed mainly of a nickel-iron alloy. The inner core is 1200 km thick and it is almost entirely composed of iron. The Earth's magnetic field is believed to be controlled by the liquid outer core. The core
The lithosphere is the hard and rigid outer layer of the earth and is made up of the crust and the solid portion of the upper mantle. The lithosphere floats over a plastic layer call Asthenosphere. The lithosphere is divided into many plates that move in relation to each other due to convective currents in the mantle.
Minerals and rocks A mineral is a naturally occurring, inorganic, solid which possesses a characteristic internal atomic structure and a definite chemical composition. Cl Na Halite (Na Cl) or rock salt, a salty mineral A rock is a natural aggregate of one or more different kinds of minerals. Marble is formed by calcite and granite is made up of quartz, feldspars and mica
Minerals can be formed by only one kind of atoms (element). P. e. : gold (Au), silver (Ag), diamond (C) graphite (C), etc But most minerals are compounds, which means they are composed of two or more different kinds of atoms, chemically combined: halite (Na Cl), calcite (Ca CO 3), quartz (Si O 2), etc
Most common minerals can be identified by inspecting or testing their physical properties such as colour, hardness, lustre or crystal form The hardness of a mineral is the resistance to scratching. Mineral hardness is rated from 1, talc (soft) to 10, diamond (hard) on the Mohs hardness scale. http: //www. sdnhm. org/kids/minerals/game s/true-false/index. html
Mach the minerals with their use 1. The main ore of aluminium is. . . 2. It is used to make glass. . . . 3. It is used to make steel. . . 4. Salty mineral extracted mainly from the sea-water. . . 5. It contains copper and sometimes gold and silver. . . . 6. It makes the lead for pencils 7. It is used in electronic components. . . 8. The main ore of lead. . . . 9. It is used to make plaster. . . . 10. It is used to cut rocks. . . Pyrite, diamond, gypsum, graphite, gold, bauxite, magnetite, quartz, halite, galena
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