Earth Science Course Material No.2 PDF

EARTH SCIENCE COURSE MATERIAL NO. 2 Source: https://na.eventscloud.com/ehome/index.php?eventid=657302&  EARTH & EARTH AS A SYSTEM WHAT WILL...

EARTH SCIENCE COURSE MATERIAL NO. 2 Source: https://na.eventscloud.com/ehome/index.php?eventid=657302&  EARTH & EARTH AS A SYSTEM WHAT WILL WHATS’ INSIDE YOU LEARN? THIS MODULE? This module has been designed to…. describe the compositional and 2 Learning Outcomes structural layer of Earth’s interior; identify the possible source of Earth’s 3 Pre-Activity magnetic field; list the characteristics of Earth’s four major spheres; 3 Earth’s Interior identify four processes in which matter and energy cycle on Earth. 4 Earth As A Magnet 5 Earth’s Gravity 5 Earth System Science 6 The Earth System 7 Earth’s Energy Budget 8 Geochemical Cycles 11 Lesson Summary 12 References Source: https://www.alamy.com/earth-core-structure-with-geological-layers-3d-rendering-image371511204.html 2|Page 1st Term, A.Y. 2024-2025 Earth Science Pre-Activity: Let’s define Earth’s system! Read the statement below and answer the question that follows. Imagine walking along a rocky coast as a storm blows in from the sea. The wind whips the ocean into whitecaps, and waves crash onto the shore. Before you have time to escape, blowing spray has soaked your clothes. A hard rain begins as you scrambled over the rocks to your car. During the adventure, you have observed the spheres of the Earth. List down the terms that are used in the statement that reflects to what made up the Earth. Categorize them based on the following: Air Water Land With Life What are the four spheres of Earth? FOCUS QUESTIONS What are the two main sources of energy in the Earth system? What are the four processes in which matter and Earth is the third planet from the sun in our solar system It is the only planet in the solar system that support life. Earth is mostly made of rock. Approximately 70% of Earth’s surface is covered by a relatively thin layer of water called the global ocean. As viewed from space, Earth is a blue sphere covered Fig. 1: Although from afar, with white clouds. Although from afar, Earth looks like Earth looks like a sphere, it is a sphere, it is an oblate spheroid or slightly flattened. an oblate spheroid. Earth’s pole-to-pole circumference is 40,007 km and Source: Allison, DeGaetamo, its equatorial circumference is 40,074 km. Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. 27pp. Explain why scientists have to rely on indirect observations to study Earth’s interior? 3|Page 1st Term, A.Y. 2024-2025 Earth Science  Earth’s Interior Scientists determined the compositions of Earth by studying seismic waves produced during earthquakes and explosions near Earth’s surface. The three compositional zones of Earth’s Interior are: crust – the thin and solid outermost layer of the Earth above the mantle mantle – the layer of rock between Earth’s crust and core core – the central part of the Earth below the mantle The boundary between crust and mantle is called mohorovicic (MOH hoh ROH vuh CHICH) or moho. Structural Zones of Earth’s Interior The three compositional zones of Earth’s interior are divided into five structural zones. Lithosphere – the solid, outer layer of Earth that consists of the crust and the rigid upper part of the mantle. Asthenosphere - the solid, plastic layer of the mantle beneath the lithosphere; made of mantle rock that Fig. 2: Earth’s interior flows very slowly, which allows tectonic plates to move on top of it. Source: https://www.google.com/search?q=parts+ of+earth&sxsrf=ALiCzsbaYCoTuaXgKQTKd_ Mesosphere - literally, the “middle sphere”; the VSrBhvv5nsnQ:1660672902496&source=l strong lower part of the mantle between the nms&tbm=isch&sa=X&ved=2ahUKEwi0zM asthenosphere and the outer core. PT- Mv5AhWCJrcAHYgIAvsQ_AUoAXoECAEQA w&biw=795&bih=915&dpr=1#imgrc=EbQf UhBioga9gM Earth as a Magnet Earth has two magnetic poles. The lines of force of Earth’s magnetic field extend between the North geomagnetic pole and the south geomagnetic pole. Earth’s magnetic field extends beyond the atmosphere and affects a region of space called the magnetosphere. Scientists believed that the source of the Earth’s magnetic field may be the liquid iron in Earth’s outer core. However, recent research indicates that the magnetic field may have another source. 4|Page 1st Term, A.Y. 2024-2025 Earth Science  Fig. 3: The magnetic field lines around Earth show the shape of Earth’s magnetosphere. Earth’s. Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Earth’s Gravity Earth, like all objects in the universe is affected by gravity. Gravity is the force of attraction that exists between all matter in the universe. Earth’s constant gravitation value is 9.8 m/s2. Weight Vs Mass Weight is a measure of the strength of the pull of gravity on an object. On Earth’s surface, a kilogram of mass weighs about 10 N. The mass of an object does not change with location, but the weight of the object does. An objects weight depends on its mass and its distance from Earth’s center. What does the difference Fig 4: As the distance between an between your weight at the object and Earth’s center increases, equator and your weight at the the weight of the object decreases. poles suggest about the shape of An object’s mass is constant as its Earth? distance from Earth’s center changes. Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. 30 pp. 5|Page 1st Term, A.Y. 2024-2025 Earth Science Earth System Science The operation of the Earth system is a result of interaction between the two most basic components of the universe: matter and energy. Matter is anything that has mass and takes up space. Energy is defined as the ability Fig 5: This threadfin butterfish is part of a system that to do work. includes other living organisms, such as coral. Together, the A system can be described by organism are part of a larger system. the system or to and from other Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. system. Holt, Rinehart and Winston. 31 pp. Closed System A closed system is a system in which energy, but not matter, is exchanged with the surroundings. Open System An open system is a system in which both energy and matter are exchanged with the surroundings. The Earth System Technically, all systems that make up the Earth are open. But the Earth system is almost a closed system because matter exchange is limited. Energy enters the system in the form of sunlight and is released into space as heat. Only a small amount of dust and rock from space enters the system, and only a fraction of the hydrogen atoms in the atmosphere escape into space. Fig 6: Energy is exchanged in both the closed system (left) and the open system (right). In the open system, matter is also exchanged. Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. 32 pp. 6|Page 1st Term, A.Y. 2024-2025 Earth Science Earth’s Four Spheres Matter on Earth is in solid, liquid, and gaseous states. The Earth system is composed of four “spheres” that are storehouses of all of the planet’s matter. Atmosphere – it is the gaseous layer above the Earth’s surface, primarily composed of 78% nitrogen and 21% oxygen. Other gases like argon, carbon dioxide, carbon monoxide, ozone, and other inert gases made the remaining 1%. The atmosphere Fig 7: Distribution of Earth’s atmosphere. supports life because animals and oxygen, Source: and plants need both carbon dioxide and https://www.toppr.com/guides/science/air- around-us/components-of-air/ oxygen. In addition, the atmosphere supports life indirectly by regulating climate. Air acts as both a blanket and a filter, retaining heat at night and shielding from direct solar radiation during the day. Biosphere – the zone of Earth where all forms of life exist: in the sea, on land, and in water. It is sometimes called as the large ecosystem. This is the zone that life inhabits. Biosphere is a very thin layer of the earth’s surface. Geosphere – the solid Earth, consisting of the entire planet from the center of the core to the outer crust. It includes the core, mantle, and crust of the Earth. Hydrosphere – the water part of the Earth which circulates among oceans, continents, glaciers, and atmosphere. Oceans cover 71% of the Earth and contain 97.5% of its water. Earth’s Energy Budget Earth’s four main spheres are open systems that can be thought of as huge storehouses of matter and energy. Matter and energy are constantly being exchanged between the spheres. This constant exchange happens through chemical reactions, radioactive decay, the radiation of energy (including light and heat), and the growth and decay of organisms. Internal Sources of Energy Earth’s interior was heated by radioactive decay and gravitational contraction. Since the Earth was formed, the amount of heat generated by radioactive decay has declined. But the decay of radioactive atoms still generates enough heat to keep Earth’s interior hot. Earth’s interior also retains much of the energy from the planet’s formation. The hot materials from Earth’s interior transfer its heat through the process of convection. 7|Page 1st Term, A.Y. 2024-2025 Earth Science Radioactive decay Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Since its formation, the Earth has been losing heat to space. Certain elements, known as radioactive elements such as potassium, uranium, and thorium, break down through a process known as radioactive decay, and release energy. This radioactive decay in Earth’s crust and mantle continuously adds heat and slows the cooling of the Earth. Primordial Heat Primordial heat is the internal heat energy accumulated by dissipation in a planet during its first few million years of evolution. The main contributions to the primordial heat are accretional energy – the energy deposited by infalling planetesimals – and differentiation energy. The latter is mainly released by core formation and is basically potential energy that is dissipated upon formation of a gravitationally stable layering of the planet. In addition to the primordial heat, the planet’s internal heat source is mainly provided by the radioactive decay of long-lived unstable isotopes such as 238U, 235U, 232Th, and 40K and by latent heat. External Energy Sources Solar energy is the most external energy source of the Earth. It supports life to continue operating. Solar radiation warms Earth’s atmosphere and surface. What do you think will happen to the materials that is less dense and to the materials that are denser? How do you think solar energy supports life on Earth? Fig 8: Incoming solar energy is balanced by Solar energy is changed into stored energy solar energy reflected or reradiated by in the wheat kernels by chemical processes several of Earth’s systems. in the wheat plant. When the wheat is Source: Allison, DeGaetamo, Pasachoff.2006. eaten, the stored energy is released from Earth Science. Holt, Rinehart and Winston. 34 pp. the wheat and used or stored by consumer. 8|Page 1st Term, A.Y. 2024-2025 Earth Science The Nitrogen Cycle Nitrogen is the most abundant element in the air. It plays vital role in building proteins. However, most organisms cannot use the atmospheric nitrogen. Nitrogen must be altered, or fixed, before organisms can use it. Nitrogen fixing is an important step in the nitrogen cycle. In the nitrogen cycle, nitrogen moves from air to soil, from soil to plant and animals, and back to the air. Nitrogen is removed from air mainly by the action of nitrogen-fixing bacteria. These bacteria live in soil and on the roots of certain plants. The bacteria chemically change nitrogen from air into nitrogen compounds, which are vital to the growth of all plants. When animals eat plants, nitrogen compounds are returned to the soil by the decay of dead animals and in animals’ excretions. After nitrogen compounds enter the soil, chemical processes release animals take part in a similar nitrogen cycle. Fig 10: The balance of nitrogen in the atmosphere and biosphere is maintained through the nitrogen cycle. Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. 36 pp. The Carbon Cycle Carbon is an essential substance in the fuels used for life processes. Carbon moves through all four spheres in a process called the carbon cycle. Part of the carbon cycle is a short-term cycle. In this short-term cycle, plants convert carbon dioxide, CO2, form the atmosphere into carbohydrates. Then, organisms eat the plants and obtain the carbon back into the air as carbon dioxide, CO2. Organisms also release carbon into the air through their organic wastes and by the decay of their remains, which release carbon into the air as carbon dioxide, CO2, or as methane, CH4. 9|Page 1st Term, A.Y. 2024-2025 Earth Science  Part of the carbon cycle is a long-term cycle in which carbon moves through Earth’s four spheres over a very long time period. Carbon is stored in the geosphere in buried plant or animal remains and in a type of rock called a carbonate. Carbonate forms from shells and bones of one-living organisms. Fig 11: Carbon moves through Earth’s four spheres in a combination of short-term and long- term cycles. Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. 37 pp. The Phosphorus Cycle Phosphorus is part of some molecules that organisms need to build cells. During the phosphorus cycle, phosphorus moves through every sphere except the atmosphere, because phosphorus is rarely a gas. Phosphorus enters soil and water when rock breaks down and when phosphorus dissolves in water. Some organisms excrete their excess phosphorus in their waste, and this phosphorus may enter soil and water. Fig 12: Phosphorus returns to the environment through decomposition. Source: https://www.google.com/search?q=phosphor us+cycle&sxsrf=ALiCzsYuRjaZAAcqM_V6POLC pt2AtZOtBQ:1660919159659&source=lnms&t bm=isch&sa=X&ved=2ahUKEwiy_4uEjtP5AhU XAIgKHXRJCMUQ_AUoAXoECAIQAw&biw=78 6&bih=915&dpr=1#imgrc=5M9JW- Ypd1w94M 5|Page 1st Term, A.Y. 2024-2025 Earth Science Plants absorb this phosphorus through their roots. The plants then incorporate the phosphorus into their tissues. Animals absorb the phosphorus when they eat plants. When the animals die, the phosphorus returns to the environment through decomposition. The Water Cycle The movement of water from the atmosphere to Earth’s surface and back to the atmosphere is always taking place. This continuous movement of water is called the water cycle. In the water cycle, water changes from liquid water to water vapor through the energy transfers involved in evaporation and transpiration. Fig 13: The water cycle is the continuous movement of water from the atmosphere to Earth’s surface and back to the atmosphere. Source: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. 38 pp. How do you think human activities affect the alteration of natural cycles? 6|Page 1st Term, A.Y. 2024-2025 Earth Science Lesson Summary ✓ Earth is an oblate spheroid that has an average diameter of 12,756 km. About 70% of Earth’s surface is covered by a relatively thin layer of water ✓ Seismic waves have revealed that Earth’s interior is composed of a series of layers of various densities. ✓ Earth has a magnetic field that extends into space in a region known as the magnetosphere. ✓ A closed system is a system in which energy enters and exits but matter remains static-neither enters nor exits. An open system is a system in which both energy and matter enter and leave. ✓ The Erath system can be thought of as consisting of four spheres-the geosphere, hydrosphere, atmosphere, and biosphere-that influence the operation of one another. ✓ Matter and energy are not created or destroyed. Matter and energy cycle between Earth’s systems. Energy, most of which is solar, is required to maintain this cycling. REFERENCES Book: Allison, DeGaetamo, Pasachoff.2006. Earth Science. Holt, Rinehart and Winston. Modeling Earth’s System. 2019. Core Knowledge Science Physical Science with Earth Science. 2009. National Geographic. McGraw-Hill. Online Sources: (2021). Retrived 3 January 2021, from https//www.esrl.noaa.gov/gmd/education/info activities/pdfs/TBI earth spheres.pdf Contributors: LESLIE Q. SARTE, LPT 7|Page 1st Term, A.Y. 2024-2025 Earth Science