Topographic Maps 101

Topographic Maps 101 The intricate details on a topographic map can be befuddling, even frustrating, if you are leaing throughout the hinterland. But once you get familiar with signs and symbols, reading maps will become friendly assistance rather than a daunting task. Topographic Maps network lines of latitude are parallel to the equator (east and west), and lines of longitude are perpendicular to the equator (north and south). These lines form a patte of squares across the surface of the earth like a chessboard. A square, formed by lines of longitude and latitude, measures 90 degrees x 90 degrees. Grades are divided into minutes and seconds. ? 1 degree = 60 minutes? 1 minute = 60 seconds The important thing to understand when we are looking for a topographic map of our hiking adventure, which is located in the larger context of degrees, minutes and seconds. Fortunately, it is also usually be identified with a place name. Another method of notation within the system of coordinates of the area is in decimal degrees. The decimal system of degrees, minutes and seconds are replaced by a percentage of a certain level, expressed as a maximum of four decimal digits long. It is often used in geographic information systems (GIS), applications, maps and topographical maps to scale Explained a topographic map lists its scale in the margin or legend. The scale is the ratio between distances on a map and the corresponding distance on the ground. For example, a map with a scale of 1:50,000 means that 1 unit on the map equals 50,000 equivalent units on the ground. The units can be inches, feet, centimeters or meters, depending on the scale map of what you are seeing and what measuring system the country uses. Most of the USGS 1:24,000 maps, also known as 7? maps minutes. In this map, 1 inch = 24.000 inches on the ground. In Canada, most hiking maps are 1:50,000 scale, where 1 cm = 50,000 centimeters on the ground. A small map (eg 1:100,000) covers a wide area, it shows less detail, with less functionality. A large map (eg 1:10,000) covers a small area, which shows a lot of details and small features. A 1:2,500, large-scale map shows individual buildings and lighting. Topographic maps symbols and colors of the symbols and colors used on the maps are quite simple:? Black - man-made? Cultural? features such as roads, buildings, etc. It 'also used to show geographical names (toponymy), certain symbols, geographic coordinates, precise elevations, border information and surround information. ? Blue? Streams, lakes, rivers, streams, etc. The list of water bodies and rivers are also shown in blue, as are magnetic declination and UTM (Universal Transverse Mercator) network. ? Brown - contour lines, contour increases, increases in place, the sand. ? Green - areas with vegetation of a forest, orchard or vineyard? Gray - used on the back of the card where the different symbols and a glossary of terms and abbreviations can be found. ? Orange - unpaved roads and highways and roads. ? Viola - Features added to the map of the first survey. These characteristics are based on aerial photographs but has not been verified on the ground. ? Red - major roads, the boundaries of public lands. A red color is used to show urban development. ? White - areas with little or no vegetation, also used to describe the permanent snow and glaciers Topographic Maps Glossary? Bearing - Angular direction expressed in degrees. ? Contour lines? A line on a map joining points of equal elevation. These lines are used to illustrate the importance on a map. ? Distortion - The difference in shape between the curves of the earth and the surface representation of a topographic map. ? Grid - A system of horizontal and vertical lines that provide coordinates to locate points on a picture. ? Magnetic declination - the angle between magnetic north and true north, expressed in degrees and minutes, east or west of true north. ? Magnetic North - The direction of the compass needle points. ? Projection - A method by which the curved shape of the earth is represented on a flat surface, overcoming the bias. ? Relief? Changes in the elevation of the earth? S surface. ? Scale? The relationship between the distance on a map and the corresponding distance on the ground. For example, a map with a scale of 1:50,000 means that 1 unit on the map equals 50,000 equivalent units on the ground. ? Topographic map? An illustration of the earth? The different levels of elevation contour lines. They are both natural and artificial. ? True North - Direction of the northe part of the rotation of the earth? the North Pole.