Topic 5 Introduction to Earth Systems PDF

Topic 5 introduction to Earth systems Lesson 2 surface features in the geosphere Grade 6 Prepared by Miss Dania Hamwiah Objectives  Understand Topography and Landforms  Explore Earth-Shaping Forces  Utilize Mapping Tools Topography of the geosphere Topogra...

Topic 5 introduction to Earth systems Lesson 2 surface features in the geosphere Grade 6 Prepared by Miss Dania Hamwiah Objectives  Understand Topography and Landforms  Explore Earth-Shaping Forces  Utilize Mapping Tools Topography of the geosphere Topography: The shape of the land, described using elevation, relief, and landforms. Elevation: Height above sea level (e.g., the highest point in the USA is Mount Whitney: 4,418m;and the lowest point is Badwater Basin: -86m). Relief: Difference in elevation between the highest and lowest points in an area. Landforms: Features such as mountains, plateaus, dunes, and rivers, different landforms have different combination of reliefs and elevations. Pg. 187  Construction and destructive forces in the geosphere The Earth's surface is continuously shaped by Pg. constructive forces that build up land and 188 destructive forces that wear it down, forming the Earth’s topography over time. 1. Constructive Forces: Definition: Forces that create or build landforms by adding material to the Earth's surface.  Examples: Mountain Formation: The Himalayan mountain range was formed as tectonic plates collided, pushing up sections of the ocean floor. Creation of new landmasses, such as volcanic islands or uplifted plateaus. Pg.18 9 Construction and destructive forces in the geosphere 2. Destructive Forces: Definition: Forces that break down or erode landforms, reducing elevation and relief.  Examples: Erosion of rocks: Caused by rain, wind, ice, and temperature changes. Natural events like landslides, earthquakes, and volcanic eruptions that release ashes into the atmosphere killing living organisms in the biosphere, but it can also enrich the soil with nutrients. Rock erosion happens due to the constant collision between water and rocks Pg. 188 1.5 times taller Exploring Earth’s surfaces  Mountains: A landform with both high elevation and high relief; grouped as ranges, systems, or belts. A. Mountain Range: A group of mountains closely related in shape, structure, location, and age. B. Mountain System: A collection of mountain ranges within a region (e.g., the Rocky Mountains). C. Mountain Belt: A larger unit formed by long, connected chains of mountain systems and ranges.  Plateaus: landforms that have high elevation, low relief; can be shaped by rivers and streams.  Plains: A landform that has low elevation and low relief, a plain that lies near the seacoast we call it coastal plains (e.g., Atlantic coastal plain).  Coastlines: The boundary the between land and the ocean or lake.  Dunes: Hills of sand piled up by the wind; they protect coasts from waves.  Rivers: Natural streams of water that flow into larger water bodies, such as oceans, lakes, or other rivers.  Delta: When a river reaches an ocean, its water slows down, and the sediments (sand, clay, and silt) sink and accumulate, forming a delta at the mouth of the river, for example, In Florida, the Apalachicola River creates a delta by supplying sand to St.  Pg. 191 mountain s glacier s Plateau s lake River Plain Coastlin Dune Delta e  Group activity- using graphical intelligence identify the names of these 1 landforms 4 2 3 lake Plateaus Delta 6 5 Mountains Glaciers Coastline 7 8 9 Plain Dunes River Modeling landforms  Modeling Landforms: Before advanced technology, scientists and mapmakers spent a lot of time walking over land and sailing along coastlines to create maps. They used a method called surveying, which involved measuring distances and elevations using tools and geometry.  Modern Mapping: Now, maps are made using computers, aerial photos, and satellite images.  Topographic Maps: These maps show the shape of the land (elevation, relief, and slopes) as if viewed from above, as bird’s-eye view.  They use contour lines to connect points of the same elevation:  The spacing of contour lines tells us about the slope: o Far apart(The outermost contour loops)=Flat areas or gradual slopes, that have low elevation. o Close together(The innermost contour loops)=Steep slopes areas that have high elevation  Contour intervals: The elevation difference between contour lines is always the same on a map “consistent”. Important note: The outer most contour loop represents the lowest elevation, like the  Index contours: Every fifth contour line is known as the index contour, they are darker base of a hill or mountain. and The easier tocontour innermost read. loop represents the highest elevation, like the peak of the mountain. Pg. 192 Around 2640 m  Reading a topographic map  Scale of Topographic Maps:  In the U.S., 1 cm on the map = 0.24 km on the real ground.  Maps show features like rivers, coastlines, and human-made structures (e.g., highways as outlines, houses as symbols).  Finding Elevation on the map:  Start at an index contour line (thicker, labeled line).  Count the number of contour lines up or down to the feature and multiply by the contour interval.  The shape of a contour line provides information:  V-shaped lines pointing away from a summit = Ridge line.  V-shaped lines pointing toward a summit = Valley.  Closed loop = Hilltop.  Closed loop with dashes inside = Depression or hollow. Ridge Depression Valley Using graphical intelligence read this topographic map, indicating valley, depression, line ridge, and hilltop Pg. 193  Aerial Photography: o Photos are taken from airplanes with cameras. o The photos capture strips of land, which are pieced together like a puzzle to create a detailed image of a large area. Pg. 194 Satellite Imagery: o Computers and satellites make mapping easier and more accurate. o Satellites collect data about Earth's surface and create satellite images made up of pixels, showing details like color and brightness. o Images reveal features such as plants, soil, rocks, water, snow, and ice. o Satellites orbit Earth to collect and store surface data. o Computers process the data to produce detailed maps and images. Pg. 194 White areas are snowy, and brown areas are deserts   Global Positioning System (GPS): Definition: A navigational system using satellite signals to determine the location of a radio receiver on Earth. Uses: Helps users (e.g., on phones or in cars) find their location or navigate. How it works: 24 satellites orbit Earth and continuously send their location and time to GPS receivers. A receiver needs data from at least 3 satellites to calculate its position accurately.  Geographic Information System (GIS): Definition: A computer-based system for creating interactive maps by combining data from GPS, satellite images, statistics, and other maps. Uses: Analyzes geographic data to identify patterns, relationships, and trends. Helps in solving problems, such as flood risk analysis by using layers of data. Data Layers: Include features like rivers, floodplain boundaries, and streets to aid city Pg. planning and decision-making. 195 Pg. 195  Thank you Prepared by Miss Dania Hamwiah