Geography revision notes
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The following are notes I somewhat typed from the textbook, this contains only the chapter 1 and chapter 2 gateway 1 for my textbook, for sec 3 geography. Some of the explanation may be wrong, as I did some my self. its about 1800 words, should be helpful, contained most stuff... Natural hazard: a naturally occurring event that threatens lives and causes damage to property. Tectonic:earthquakes, volcanic eruptions, tsunamis. Climate related: droughts, floods, tropical cyclones. Core: 3300 km thick, temp in 3000 to 5000. Mantle, 2900km thick, between 800-3000 Crust, a few km to 70km thick. Lithosphere, crust and uppermost mantle. Why do tectonic plates move? Convectional currents are movements of heat within the mantle. Materials in the mantle is heated by the core, causing the mantle material to expand, rise and spread out beneath the plates. This causes the plates to be dragged along and to move away from each other. Then, the hot mantle material cools slightly and sinks, pulling the plates along. The sinking mantle material heats up again as it nears the core and the whole process repeats. The slab pull force occurs when a denser oceanic plate is forced beneath a less dense continental plate or oceanic plate in a process called subduction. As the plate subducts,it pulls the rest of the plate along. The subducting or sinking plates drives the downward-moving portion of convection currents. The mantle material which is found away from where the plates subducts drives the rising portion of convection currents. Divergent plate boundaries. Oceanic x2, ridges, such as the mid Atlantic ridge. The magma rises after the plates move apart, this causes the hot magma to rise. The magma rises and cools., volcanic islands are formed when the magma builds up to the sea level, and formes a island. Continental x2, rift valleys are formed, active volcanoes and earthquakes can be found along the rift valleys which the continental plates are diverging. Such as the east African rift valley. Convergent plate boundaries. Oceanic x2, trenches, such as the Mariana trench. The denser pacific plate subducts under, it melts and the magma rises and the Marianna islands are formed. Earthquakes may also occur, causing tsunamis. Continental x2, fold mountains are formed due to the pressure. The Himalayas is an example. Between the Indian plate and the Eurasia plate. Oceanic continental, the denser oceanic subducts under, forming a trench and fold mountains / volcanoes. This is as the plate melts and the magma rises. The Australian plate, the Sunda trench, the barisan mountains and the Eurasian plate. Transform plate boundaries, north Anatolian fault, fault lines are formed. Anticline is the highest part or the up part of an fold mountain and the down fold is called the syncline. Rift valleys and block mountains. They are formed along fault lines, the tensional force moves the block mountains apart from the fault line and then forming rift valleys. Pg23 Volcanoes A magma chamber(where magmas are stored) , vents(openings on the earth's surface linked to the magma chamber), the upward motion of volcanoes are known as vulcanicity. Magma rises from the magma chamber to the surface and it is know as lava after that. Lava builds up around the vent, solidifying to form a small volcanic cone. The bowl shaped opening is called the crater. When a volcano erupts, lava, ash and rock fragments are released. The force of the volcanic eruptions depends on the amount of pressure and gas in the magma. The summit of a volcano may be blown off during an explosive eruption. The sides of the crater collapse inwards due to the loss of structural support. As a result, a large depression known as a caldera is formed. New eruption of lava covers the ash layer and builds un the volcano. During the formation of the volcano, the vent may become blocked. This forces the magma to find a new exit route to the surface. A secondary cone of newer volcanic material will then develop. The viscosity refers to the stickiness of the lava or its resistance to flow, low-silica lava has a lower viscosity which results in less explosive volcanic eruptions. This type of lava allows gases to escape easily and flows more easily through the vent before reaching the surface. As shield volcano are formed by low silica lava or lava with low viscosity, there is a gentle slope. Strato volcanoes are formed by high silica lava or lava with high viscosity, this kind volcano has a higher and steeper volcano. Secondary vents are also formed when magmas rises out from its secondary vents. The pacific ring of fire, a ring of "fire" on the Pacific ocean. Earthquakes: The focus is the point which the earthquake happened, and the epicenter is the place directly above the focus on the earth's surface. For deep focus earthquakes, the focus is about 70km to 700 km below the earth's surface. There are smaller impacts.The shallow focus earthquake occurs in the upper 70km of the earth's crust. The factors: Population density,The level of preparedness,Distance form the epicenter,The time of occurrence , Type of soil,Location of earthquake. As seismograph is used to record the seismic waves released by an earthquake. Tsunami, caused by earthquakes, may start off even as just 1m, but as the water gets shallower, the wave becomes higher. Also, when the tsunami is about to hit, the water will retreat first. Earthquake can cause: Disruption of services, Fire, Landslides, Destruction of properties, Destruction of infrastructure, Loss of lives Indonesia, 9.2, 228000. Haiti, 7.0, 300,000. Volcanoes, landslide caused by the collapse of a volcanic cone during a volcanic eruption. Destruction by volcanic materials. Pollution Effects of the weather (volcanic winter) Benefits, fertile volcanic soil, precious stones and minerals; building materials. Tourism and geothermal energy. Fatalistic approach, accepted as unbelievable events. Acceptance approach, accepts the risks. Adaptation approach, well-prepared. Land use regulations, building design, infrastructure development, emergency drills and use of technology. Short term responses, tents, medical aid, food,water, calling for humanitarian aid, searching and rescuing, handling the status(emergency services etc) Long term, improving infrastructure, compensating people who lost their land and property, ensuring the affected region recovers economically, improving health options. Weather is the condition of the atmosphere at a particular place and time, the atmosphere is a layer of air surrounding earth. The weather affects how we live from day to day. The climate is the average condition of the atmosphere of a specific place over a long period of time, usually over 30 years. Temperature is the degree of hotness or coldness of a place. This is determined by the energy from the sun. High temperature is anything above 20 degrees celcius, and low temperature is anything below 10 degrees celcius The surface of teh earth heats up, which in turn heats up the atmosphere. Mean daily temperature, diurnal(day) temperature range, mean monthly temperature,mean annual temperature, annual temperature range. Factors: Latitude: the "concentration" of sun rays, or the amount of sunrays concentration. A place with latitude of 0n receives more sunlight concentration than a place with 90n Altitude: the height in short, above sea level. The higher the altitude, the colder it is as there are less air concentration and the air is less dense. Thus, less sunrays are absorbed. Also, the surface area is significantly smaller. Distance from the sea: the maritime effect of which is a preserving effect that large water bodies have on the climate of coastal areas. It causes coastal areas to have smaller annual temperature range. This is because the sea cools and heats slower than land. The continental effect is the effect that continental surfaces have on the climate of in land areas, it causes the land to have larger annual temperature ranges than the coastal areas near to the sea. Cloud cover: the clouds absorb the incoming solar rays and reflect the heat going out, thus, giving a preserving effect. This mean the more cloud cover the less day night temperature range. So the diurnal temperature range is smaller. Relative humidity: the amount of water in the air right now to the amount of water vapour the air can hold, the colder it is, the less water vapour the air can hold. Saturation of which happens at 100% relative humidity causes clouds to be formed with the help of condensation nuclei and also, the temperature of which saturation happens is known as dew point. Clouds are formed mainly due to evaporation of water vapors, which causes saturation at the dew point and which condensation takes place when there are tiny particles called the condensation nuclei for the water vapour to condense on. A cloud is a visible mass of water or ie crystals that are suspended in the atmosphere. The water droplets may eventually grow large enough to fall to the earth's surface as precipitation. Areas with above 1500 mm are considered having high rainfall, and areas with below 250 mm are classified as having low rainfall. Convectional rain occurs when the earth's surface is heated intensely, hence, this type of rain is common in the tropics where a larger amount of sunlight is received. The air heats up by the surface by the sun rays, and thus, become unstable. The air rises and expands and as the air rises, its temperature begins to drop and when it reaches dew point, condensation occurs and clouds become large and heavy enough, they fall to the ground as rain. Often associated with lightning and thunder. Last only a short time and is very intense. Relief rain: only occurs to places with a mountain(above 600m, which Singapore does not have) close a place with large amount of water bodies. This is because the warm moist air rises, cools and forms clouds. The rain falls on the mountain and when it reaches the leeward side(opposite to the windward side, which is the side facing the water) it is dry and no rain falls. Wind, formed by air pressure and of which blows from high pressure to low pressure. Beaufort scale is used to measure it. Land breeze:night Sea breeze: day Caused by pressure difference The southwest monsoon,between June and September. Where it is winter in Australia and summer in central Asia *insert 1000 word essay here on monsoons. The north east monsoon, between October and February. Winter in central Asia and summer in Australia. *insert 1000 word essay here on monsoons. Equatorial climate: between 10N south and north of equator, hot, small annual temperature. Monsoon climate: between 5 and 25 N north and south of the equator. High annual mean temperature, not as high, about 6c in temperature range. Cool climate, marine west coast climate: 45 to 60 south and north of the equator, 4 distinct seasons, ranging between -3 to 22. Range of about 25. Lower total rainfall, evenly distributed throughout the year. That's all -Bill.Cui
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if my notes were like this, it is no wonder i dun feel like studying.
it's ok, i just wait for the spark.
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There's one very easy way to get the spark.
Electrocute yourself while studying.
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I would study better if geography notes are like this :
