2 GSAR EXPECTATION Map and compass skills are not optional for searchers. All searchers MUST be able to use a map and compass easily and effectively.
3 TOPOGRAPHIC MAPS A MAP is a pictorial representation of a portion of the earth s surface. The most useful and commonly used map by the searcher is the TOPOGRAPHIC MAP, which can be defined as: A two dimensional representation of the three dimensional configuration of a land surface.
4 Example of a 1:10000 scale Searcher Map
5 Example of an Orthographic Map
6 TOPOGRAPHIC MAPS Advantages Of A Topographic Map: Represent physical features of the earth s surface without distortion. Made to scale (1:10000) which means there is a ratio of a distance on the map to the actual distance on the ground. Have grids which allow the searcher to describe a point on a map with great accuracy. Provide a wealth of information about a particular location.
7 MAP CONVENTIONS Topographic maps have a wide variety of applications, but all follow the same general conventions. Maps are made with North at the top. A black margin frames the ground area represented. The Title, Scale, Contour Interval, Reference Systems, Legend and other information are shown outside and are usually displayed along the bottom or right margin. Topographic map symbols are usually displayed on the back of the map.
8 SCALE The scale of a map is a ratio between a unit of length on the map and the actual distance represented on the ground. The 1:10000 map scale is the most commonly used by ESGSAR. This scale simply states that 1cm on the map equals cm (100 m) on the ground.
9 MEASURING DISTANCE Two common methods searchers use to measure distance are: Estimating distance by counting the number of map squares between two objects. On our 1:10000 searcher maps, the distance between each grid line is 200 m. Measuring the distance between two objects with a metric ruler. On a 1:10000 map, each cm on the ruler equals 100 m. Each mm equals 10 m.
10 Measuring distance between SCHOOL and CAMP
11 MEASURING DISTANCE EXERCISE Using the provided 1:10000 searcher map, determine the following distances in meters: A) The distance between the ESGSAR BUS and the SCHOOL. B) The distance between the SCHOOL and the CAMP. C) The distance between the CAMP and the ESGSAR BUS. D) The distance between Waypoint #4 and the SCHOOL.
12 MEASURING DISTANCE EXERCISE ANSWERS A) BUS and the SCHOOL: 410 m B) SCHOOL and the CAMP: 1200 m or 1.2 km C) CAMP and the BUS: 1130 m or 1.1 km D) Waypoint #4 and the SCHOOL: 710 m
13 GRID REFERENCE SYSTEMS Topographic Maps have two types of grid reference systems: Geographic (Latitude and Longitude) Universal Transverse Mercator (UTM) SAR in Nova Scotia uses UTM
14 Latitude and Longitude are NOT generally used by GSAR teams.
15 GRID REFERENCE SYSTEMS Universal Transverse Mercator (UTM) The UTM grid is a ground based system. The grid consists of a system lines forming squares over the entire map. The area of a square depends on the map s scale.
16 GRID REFERENCE SYSTEMS (UTM cont d) The entire UTM grid system is comprised of 100 x 100 kilometre blocks. The grid lines are numbered and printed along the borders of the map and at intervals on the map area. Using the UTM system, any point can be designated to an increment of 1 metre. The UTM system is commonly called the Military Grid Reference System.
18 GRID REFERENCE SYSTEMS (UTM cont d) A grid map reference is given by a zone and pair of numbers (an Easting and a Northing). The zone for mainland Nova Scotia is 20 and does not have to be given. A UTM map reference looks like: E N The Northing represents the distance from the Equator in meters.
19 GRID REFERENCE SYSTEMS (UTM cont d) The Easting represents the distance from the centre of the zone arbitrarily set at meters The Easting has 6 digits and the Northing has 7. The Easting is always read first. Using a metric ruler and a 1:10000 map, you can determine the location of an object within 10 meters or better.
20 Center of Zone Line Zone 20
21 500,000E Center of Zone line passing through Jeddore 500,000E
22 MAP CONVENTIONS 