Lesson 1: Earth Systems PDF

1st Quarter LESSON 1 Week 1 Earth and Life Science  OBJECTIVES At the end of the lesson the student must be able to: Describe the uniqueness of earth in terms of its physical properties Identify the properties possessed by Earth necessary to support life Descri...

1st Quarter LESSON 1 Week 1 Earth and Life Science  OBJECTIVES At the end of the lesson the student must be able to: Describe the uniqueness of earth in terms of its physical properties Identify the properties possessed by Earth necessary to support life Describe the four subsystems of Earth Explain the water cycle  INTRODUCTION Earth Science looks at the entire planet as a system of interacting parts called subsystems. It focuses on the changes within and among these parts. Each subsystem can be separately, but ultimately, they are dependent on and connected with the other subsystems. Earth is composed of four basic subsystems: geosphere, hydrosphere, atmosphere, and biosphere.  The Earth is Unique! § The planet Venus, Earth and Mars are part of the terrestrial or rocky planets. Their composition and densities are not too different from each other. § Venus is considered to be the Earth’s twin planet. It has a very similar size and mass with the Earth. § Mars is about half of the Earth’s mass.  The Earth is Unique! Orbital period and velocity are related to the planet's distance from the sun. Among the three planet, Venus is the nearest and Mars is the farthest from the Sun. Rotational speed of Earth and Mars are very similar. Rotational speed of Venus is extremely slow. Abundance of liquid water on Earth, hence the blue color. The Earth is a habitable planet. FACTORS THAT MAKE A PLANET HABITABLE FACTORS THAT MAKE A PLANET HABITABLE Why is there life on Earth? by OpenMind https://www.youtube.com/watch?v=Y2BclOxSvfk THE EARTH SYSTEM A system is a set of interconnected components that are interacting to form a unified whole. The Earth system is essentially a closed system. It receives energy from the sun and returns some of this energy to space. THE EARTH SYSTEM The Earth is a system consisting of four subsystems : 1. Atmosphere 2. Geosphere 3. Hydrosphere 4. Biosphere  ATMOSPHERE The word atmosphere comes from the Greek roots “atmos” which means gas, and “sphaira “which means globe or ball. The atmosphere makes up of all the gases on Earth. The atmosphere is the thin gaseous layer that enveloped the geosphere. The present atmosphere is composed of 78% nitrogen (N), 21% oxygen (O2), 0.9% argon, and trace amounts of other gases. ATMOSPHERE One of the most important processes by which the heat on the Earth's surface is redistributed is through atmospheric circulation. There is also a constant exchange of heat and moisture between the atmosphere and the hydrosphere through the hydrologic cycle. GEOSPHERE Geo is a Greek root which means ground. Geosphere includes all the soil, rocks, and minerals present in the crust to the core of the Earth. It is divided into three layers namely crust, mantle, and core (metallic liquid outer core, and the solid metallic inner core).  GEOSPHERE The geosphere includes the rocks Plate Tectonics is an important of the crust and mantle, the process shaping the surface of metallic liquid outer core, and the Earth. The primary driving the solid metallic inner core. mechanism is the Earth's internal heat, such as that in mantle convection. BIOSPHERE The biosphere is the set of all life forms on Earth. It covers all ecosystems—from the soil to the rainforest, from mangroves to coral reefs, and from the plankton-rich ocean surface to the deep sea. BIOSPHERE For the majority of life on Earth, the base of the food chain comprises photosynthetic Carbon Dioxide (CO2 )is sequestered from the atmosphere, while oxygen is released as a by-product. The biosphere is a CO2 sink, and therefore, an important part of the carbon cycle. HYDROSPHERE Hydro is a Greek root which means water. About 70% of the Earth is covered with liquid water (hydrosphere) and much of it is in the form of ocean water. Only 3% of Earth's water is fresh: two-thirds are in the form of ice, and the remaining one-third is present in streams, lakes, and groundwater. WATER CYCLE Water cycle, also called hydrologic cycle, cycle that involves the continuous circulation of water in the Earth-atmosphere system. Of the many processes involved in the water cycle, the most important are evaporation, transpiration, condensation precipitation, and run-off. Although the total amount of water within the cycle remains essentially constant, its distribution among the various processes is continually changing. WATER CYCLE EVAPORATION It is the transfer of water from the surface of the Earth to the atmosphere. Evaporation is one of the major processes in the cycle. By evaporation, water in the liquid state is transferred to the gaseous or vapor, state. This transfer occurs when some molecules in a water mass have attained sufficient kinetic energy to eject themselves from the water surface. WATER CYCLE EVAPORATION Evaporation from snow and ice, the direct The main factors affecting evaporation conversion from solid to vapor, is known as are temperature, humidity, wind speed, sublimation. and solar radiation. The direct measurement of evaporation, though desirable, is difficult and possible only at point locations. The principal source of water vapor is the oceans, but evaporation also occurs in soils, snow, and ice. WATER CYCLE TRANSPIRATION Transpiration is the evaporation of water through minute pores, or stomata, in the leaves of plants. For practical purposes, transpiration and the evaporation from all water, soils, snow, ice, vegetation, and other surfaces are lumped together and called evapotranspiration, or total evaporation. WATER CYCLE Water vapor is the primary form of atmospheric moisture. Although its storage in the atmosphere is comparatively small, water vapor is extremely important in forming the moisture supply for dew, frost, fog, clouds, and precipitation. Practically all water vapor in the atmosphere is confined to the troposphere (the region below 6 to 8 miles [10 to 13 km] altitude). WATER CYCLE CONDENSATION The transition process from the vapor state to the liquid state is called condensation. Condensation may take place as soon as the air contains more water vapor than it can receive from a free water surface through evaporation at the prevailing temperature. This condition occurs as the consequence of either cooling or the mixing of air masses of different temperatures. WATER CYCLE PRECIPITATION, INFILTRATION AND RUN-OFF By condensation, water vapor in the atmosphere is released to form precipitation. Precipitation that falls to the Earth is distributed in four main ways: 3. some percolates into the soil by 1. some is returned to the infiltration, and the remainder flows atmosphere by evaporation, directly as surface runoff into the sea. 2. some may be intercepted by 4. Some of the infiltrated precipitation may vegetation and then evaporated later percolate into streams from the surface of leaves, as groundwater runoff. WATER CYCLE PRECIPITATION, INFILTRATION AND RUN-OFF WATER CYCLE REFERENCES Earth and Life Science Teacher’s Guide Earth and Life Science Learner’s Material Earth and Life Science Teacher’s Manual https://www.youtube.com/watch?v=Y2BclOxSvfk) https://www.soas.ac.uk/cedep-demos/000_P500_ESM_K3736 Demo/unit1/page_15.htm https://www.britannica.com/science/water-cycle