| |
| |
|
Mahavir Information |
| ||||||||
|
Topographic Maps 101
The intricate details on a topographic map can be befuddling, even frustrating, if you are learning while out in the backcountry. But once you get familiar with the markings and symbols, reading maps will become a friendly aid, rather than a dreaded assignment. Topographic Maps Grid System Lines of latitude run parallel to the equator (east and west), and lines of longitude run perpendicular to the equator (north and south). These lines form a pattern of squares across the surface of the earth like a checker board. One square, formed by lines of longitude and latitude, measures 90 degrees x 90 degrees. Degrees are further subdivided into minutes and seconds. ? 1 degree = 60 minutes The important thing to understand, when we look for a topographic map for our hiking adventures, is that it will be located within this larger context of degrees, minutes, and seconds. Fortunately, it will also, usually, be identified with a place name. An alternative method of notation within the Geographic Coordinate System is the decimal degree system. In the decimal degree system, minutes and seconds are replaced by a percentage of a degree, expressed as a decimal up to four places long. It is often used for Geographic Information Systems (GIS) applications, Topographic Maps Scale Explained A topographic map lists its scale in the margin or legend. The scale is the relationship 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 of measurement on the map equals 50,000 equivalent units on the ground. Units can be in inches, feet, centimeters, or meters, depending on what scale map you are looking at and what measuring system the country uses. Most USGS maps are 1:24,000, also known as 7 ½ minute maps. On 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 cm on the ground. A small scale map (ex. 1:100,000) covers a large area; it shows less detail with fewer features. A large scale map (ex. 1:10,000) covers a small area; it shows great detail and small features. A 1:2,500, large scale map would show individual houses and street lights. Topographic Maps Symbols and Colors The symbols and colors used on Topographic maps are fairly straight forward: ? Black - man-made, "cultural," features such as roads, buildings, etc. It is also used to show geographical names (toponymy), certain symbols, geographic coordinates, precise elevations, border information and surround information. ? Blue -water, lakes, rivers, streams, etc. The names of bodies of water and water courses are also shown in blue, as are magnetic declination and UTM (Universal Transverse Mercator) grid information. ? Brown - contour lines, contour elevations, spot elevations, sand. ? Green - areas with substantial vegetation like a forest, orchard, or vineyard ? Grey - used on the back of the map where the different symbols and a glossary of terms and abbreviations can be found. ? Orange - unpaved roads and unclassified roads and streets. ? Purple - features added to the map since the original survey. These features are based on aerial photographs but have not been checked on land. ? Red - major highways; boundaries of public land areas. A red tint is used to show an urban development. ? White - areas with little or no vegetation; also used to depict permanent snowfields 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 relief on a map. ? Distortion - The difference in shape between the actual curved surface of the earth and the flat representation of a topographic map. ? Grid - A system of horizontal and vertical lines that provide coordinates for locating points on an image. ? Magnetic Declination - The angle between magnetic north and true north, expressed in degrees and minutes, east or west from true north. ? Magnetic North - The direction your compass needle points. ? Projection - A method by which the curved shape of the earth is represented on a flat surface, overcoming distortion. ? Relief - The variations in elevation of the earth's surface. ? Scale - The relationship between 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 of measurement on the map equals 50,000 equivalent units on the ground. ? Topographic Map - An illustration of the earth's different elevation levels by means of contour lines. They present both natural and manmade features. ? True North - Direction of the northern rotational axis of the earth - the North Pole. Outdoors Adventurer, Writer and Webmaster Will Robertson lives with his family in Little Rock, Arkansas. Explore the best hiking vacations and gear on the planet at: http://www.hiking-vacations-and-gear.com
MORE RESOURCES:
Acne - Google News |
|
|
|
RELATED ARTICLES
Trekking Poles And Walking Sticks Are walking sticks longer than trekking poles? What about hiking staffs and hiking sticks? Whatever you call them, and whatever their differences, they are supposed to help your knees more than anything. This they do very well, at least when you're going downhill. Zambia Safari Top Five National Parks Zambia is Africa's best kept secret as far as safaris go. The country is a virtual unknown in comparison to other more traditional destinations but a Zambia safari can be every bit as good and in some cases even better. Creative Camp Cooking For most people, outdoor cooking is synonymous with barbeque, but there are many other ways to cook outdoors. If you have been camping, you are probably at least familiar with the portable propane stoves which provide a burner or two similar to the stovetop burners you have at home. Bird Watching Journals - Preserve Your Bird Watching Experiences Bird Watching is a great way to escape the rat race and be one with nature. Alas, your bird watching experiences can fade with time. Spanish Courses in Spain Spain: sun, sea, sand and Spanish.. Inflatable Boats: An Overview Inflatable boats are made from flexible material, usually rubber, canvas, or neoprene, and hold air at high volume but low pressure. They need to be fitted with a frame to which an oarlock mount is firmly attached. The Kuan Yin Shrine, Bangkok - the Goddess of Mercy on the Chao Phraya The Kuan Yin Shrine in Bangkok is in an old Chinese building within a community on the Chao Phraya River where time seems to have stood still for the last 200 years.The site originally had two shrines built in the reign of King Taksin (1767 - 1782) by his Chinese supporters. Top Five African Safari Destinations Any vacations in Africa will not be complete without going on a safari to experience the wild animals and the peace and tranquillity of the bushveld.But there are literally hundreds of national parks and wildlife areas in Africa that you can travel to. Unforgettable Cape Cod Vacations: The National Seashore Gift Take a captivating trip through the Cape Cod National Seashore with miles of white sandy beaches, trails and hikes to take your breath away, and majestic dunes. Just keep reading and you can visit all those places right now. Protection from Lightning - Smart Strategies for Hikers and All Outdoor Enthusiasts Prevention is your best protection against lightning. Be sure to check your local weather report before you head outside. River Cruise in Bangkok - Sightseeing on the Chao Phraya A river cruise in Bangkok gives an insight to the community life on the Chao Phraya River and the legacies on this river of kings, a picture of stark contrasts.It needn't have to be an elaborate affair; you can cut the frills and expenses. Taking an Alaskan Cruise - What to Pack Packing in general can be a hassle. But when going on an Alaskan cruise, it can be even harder because of the colder weather. San Francisco Beaches When you are planning a vacation to Maui or Rio de Janeiro you may put beaches on the top of you list of things to see. However, when planning a trip to San Francisco, you may have heard of North Beach, but North Beach doesn't have any beaches (though the neighborhood was named after a beach that used to be on its north shoreline). Backcountry Safety - An Essential 10-Point Checklist The call of the wild can be seductive. The exquisite beauty of the wilderness, the incomparable solitude, the simplicity of life on the trail, and the rush of living a bit on the edge attract thousands of eager backcountry enthusiasts. Boston Vacations: Four Ways To Experience Beantown Boston is a great destination city for a vacation. There's plenty on tap to see and do, and it's an easy city to get around on foot. Kayak Travel and Trips If you love the thrill and adventure of kayak travel, the waters and lakes are yours to explore! Mankind has always been drawn to the sea and a kayak trip is truly one of the ultimate highs as far as kayak travel is concerned. Human beings have always invented useful devices that enhance our lifestyles and kayak travel is a great and marvelous feat, which blends excitement, fun and freedom of movement in one great adventure. True North & Magnetic Declination - A Trick to Make it Stick Magnetic declination is an essential principle to understand when navigating your way through the wilds with map and compass.Yet it's a tricky thing to remember, at least the way it has traditionally been taught, using an addition / subtraction method. Bird Watching Mecca - 338 Species At Acadia National Park When it comes to birding, Acadia National Park is a mecca for sightings. The Park has 338 bird species, which is a record for any national park in the United States. Holidays in Goa Sun, Sand and Surf - an apt description for Goa? But Goa is much more. Ancient temples and old churches? Yes. 4 Steps to an Enjoyable Hike Some people have fought many years of their lives to preserve the rich heritage of the outdoors and nature we now enjoy. That dedication and effort has been rewarded by fantastic hiking opportunities in our local, state, and national park systems.
|
||||||||||||||||||||
| Home | Site Map Copy Right 2006 Mahavir.com |
| NISL | Herbal Acne Solutions | Promotion Factory | Web Design | Online University Degree | College & University | GtpInfo | VPayU |
