Earth Subsystems PDF

The Earth By: Ms. Maria Niña R. Cresencia Learning Competency: Describe the characteristics of Earth that are necessary to support life.  EARTH It is the third planet from the Sun and the fifth largest planet in the solar system in terms of size and mass. Its nea...

The Earth By: Ms. Maria Niña R. Cresencia Learning Competency: Describe the characteristics of Earth that are necessary to support life.  EARTH It is the third planet from the Sun and the fifth largest planet in the solar system in terms of size and mass. Its near-surface environments are the only places in the universe known to harbor life.  EARTH It is located in the Orion-Cygnus Arm, one of the four spiral arms of the Milky Way, which lies about two- thirds of the way from the center of the Galaxy.  EARTH Earth and other planets in the solar system formed about 4.6 billion years ago. The early Earth had no ozone layer and no free oxygen, lacked oceans and was very hot. Characteristics of the Earth 1. Shape of the Earth The shape of the Earth is oblate spheroid. Astronomers believed that because of the shape of the Earth, if affects the weight of the person, motions of the moon and other artificial satellites as the Earth is on its rotation. 2. Motions of the Earth 2.1. ROTATION The Earth moves around its imaginary line known as axis. 23 hours & 56 minutes or 24 hours (complete solar day or one day) 2. Motions of the Earth 2.2 REVOLUTION The Earth orbits around the Sun. 365 and ¼ days (one solar year or one year) APHELION – the Earth is far from the Sun PERIHELION– the Earth is near to the Sun Revolution of the Earth around the Sun 3. Earth’s Seasons The Earth is tilted on its axis at an angle of 23 and ½ degrees with the North Pole that points to the same direction. Spring, Summer, Autumn, Winter 3. Earth’s Seasons Spring (Vernal) Begins on 20th or21st of March in the Northern Hemisphere. The daytime and night time of the Earth is same as 12 hours. Summer Begins on 20th until 22nd day of June. Northern Hemisphere is directly exposed in the Sun hence, days become warmer and longer. Autumn (Fall) Begins on 22nd or 23rd day of September. The Sun is directly above the equator in the Northern Hemisphere. There is a 12-hour of days and nights all over the globe. Winter Begins on 21st until 22nd day of December. Nights are longer compared to days. The longest night occurs every 22nd day of June in the South while 22nd day of December in the North. Solstice vs. Equinox Solstices are the longest and shortest days of the year, while equinoxes occur when the day and night are equally as long. 4. Magnetic Field of the Earth Earth is considered as a “giant magnet”. It enables or protects every living and non- living matter against harmful coming from the Sun. It is also the reason why we are able to see the beautiful auroras at night in the thermosphere as the layer of the atmosphere. 5. Earth’s Moon LUNA – The only moon of the Earth. It is a natural satellite of the Earth. It orbits around the Earth travelling at a speed of 3,679 km/hr. Distance varies from about 356,334 kms. 5. Earth’s Moon Its perigee (closest approach to Earth) is 405,503 kms while its apogee (farthest point) is 384,392 kms. It revolves together with the Earth every year. 5. Earth’s Moon CRUST – composed of lighter materials MANTLE – rich in silica CORE – with high presence of metallic materials Phases of the Moon Solar Eclipse It happens when the moon is between the Sun and the Earth having alignment on the same plane. The moon casts a shadow on Earth causing the sun to go dark. Solar Eclipse PENUMBRA – space of partial illumination UMBRA – central dark part of a sunspot. Lunar Eclipse It happens when the Earth is between the Sun and the moon having the alignment on the same plane. The Earth casts a shadow on the moon causing the moon to go dark. Solar and Lunar Eclipse 6. Earth’s Composition Earth is composed of bodies of water and areas of land which also make up its outermost structure.  The Earth Subsystems By: Ms. Maria Niña R. Cresencia Learning Competency: Explain that the Earth consists of four subsystems, across whose boundaries matter and energy flow.  SYSTEM It is defined as a set of interconnected components that are interacting to form a unified whole. Earth Science looks at the entire planet as a system of interacting parts called SUBSYSTEMS.  CLOSED SYSTEM It is a system in which there is only an exchange of heat or energy and no exchange of matter.  The Earth Subsystems  1. GEOSPHERE The geosphere refers to the solid Earth. The lithosphere refers to the crust and uppermost mantle. Earth’s Layer  Layers of the Earth CRUST – continental & oceanic MANTLE – upper & lower CORE – inner and outer  CRUST It’s the light and very thin outer skin of the Earth. Two types: a. Continental (land) b. Oceanic (water)  Element Amount in % OXYGEN 46.60 % SILICON 27.72 % ALUMINUM 8.13 % IRON 5.00 % CALCIUM 3.63 % SODIUM 2.83 % POTASSIUM 2.59 % MAGNESIUM 2.09 % TITANIUM 0.40 % HYDROGEN 0.14 %  MANTLE Less dense layer Made up of silicate rocks, mostly made of the elements: Si, O, Fe, Mg CORE Denser layer The Earth’s magnetic field strengthens the idea that the Earth’s outer core is molten/liquid and the inner core is solid.  2. HYDROSPHERE About 70% of the Earth is covered with liquid water (hydrosphere) and much of it is in the form of ocean water. 2. HYDROSPHERE It is the totality of Earth’s water, including the permanently frozen parts called cryosphere. 2. HYDROSPHERE 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. Hydrologic/ Water Cycle 1. Evaporation 2. Condensation 3. Transpiration 4. Precipitation 5. Infiltration 6. Surface Runoff EVAPORATION It is the process by which water changes from a liquid to a gas or vapor. CONDENSATION It is the process by which vapor in the air is changed into liquid water.  TRANSPIRAT ION It is the evaporation of water through minute pores, or stomata, in the leaves of plants. PRECIPITAT ION It is water released from clouds in the form of rain, freezing rain, sleet, snow or hail. INFILTRATION It is the process by which precipitation or water soaks into subsurface soils and moves into rocks through cracks and pore spaces. SURFACE RUNOFF It is water, from rain, snowmelt, or other sources, that flows over the land surface, and is major component of the water cycle. 3. ATMOSPHERE It is the thin gaseous layer that envelopes the lithosphere. 3. ATMOSPHERE It is the mixture of gases that surround the planet such as N, O, Ar, CO2 and water vapor. 3. ATMOSPHERE The present atmosphere is composed of 78% nitrogen (N), 21% oxygen, 0.9% Argon and 0.1% trace amount of other gases. TROPOSPHERE It is the lowest and thinnest layer. The boundary between the troposphere and stratosphere is called the tropopause. STRATOSPHERE It is less dense (less water vapor), temperature increases with altitude, almost no weather occurrence, contains high level of ozone. MESOSPHERE Gases are less dense. Temperature decreases as altitude increases. This is where meteorites burn up before they reach the Earth. THERMOSPHERE Temperature increases with altitude. Readily absorbs solar radiation. THERMOSPHERE EXOSPHERE – is where the satellites orbit Earth THERMOSPHERE IONOSPHERE – contains a high concentration of ions and free electrons and is able to reflect radio waves. 4. BIOSPHERE It includes all life forms, even organic matter that has not yet decomposed. 4. BIOSPHERE Most life on Earth exists within a zone no wider that 20 km where interactions between the lithosphere, hydrosphere, and atmosphere create a habitable environment. THANK YOU!