October 9 th, 2011

 Let's look at our first topic under Mapping Skills - Contour Lines.

 A contour line on a map is a line that joins points of equal elevation.

 The contour line represented by the shoreline separates areas that have elevations above sea level from those that have elevations below sea level

 Lets review the basics of Latitude and Longitude

 (shown as a horizontal line) is the angular distance, in degrees, minutes, and seconds of a point north or south of the Equator. Lines of latitude are often referred to as parallels.

 Degrees latitude are numbered from 0° to 90° north and south  Each degree of latitude is about 69 miles (111 km) apart

 (shown as a vertical line) is the angular distance, in degrees, minutes, and seconds, of a point east or west of the Prime (Greenwich) Meridian. Lines of longitude are often referred to as meridians

 The degrees continue 180° east and 180° west where they meet and form the International Date Line in the Pacific Ocea

 To precisely locate points on the earth's surface, degrees longitude and latitude have been divided into minutes (') and seconds

 Scale  A map represents some portion of the earth or sky on a two dimensional surface. The size of the individual features need not be indicated if a map scale is given

 two dimensional feature of the earth’s surface.  eg road map, city plan, drainage network map, map showing political boundaries

 shows three dimensional features of the earth’s surface, that is, the relief or topography of the land surface or ocean floor through the use of contour lines

 Map scale expresses the relationship(ratio) between distance on the map and the true distance on the ground (In reality)  Every Map should have its scale clearly indicated  Ex: 1:90000

Lesson 2: October 22, 2010

 According my source in BC there would be no reason to use a calculator on the Geography Provincial exam  Review Homework  Scale  Gradient  Military Grid and Map Symbols  Topographic map Interpretation  Air Photo Interpretation

 Let's look at how to calculate gradient which is a measurement of the steepness of the land or simply slope

 A method to locate points on a map.  With this method, a system of numbered lines is superimposed on a map and position is stated by quoting the numbers of the lines that intersect at the point in question.

 Let's look at some basic guidelines to assist you in interpreting an air photograph

 Shape  Cultural features: - some features such as airport runways have a distinctive shape which make them easy to identify  Natural features-- quite easy to tell the difference, for example, between an orchard (rows of trees with regular spacing) and a forest area with irregular tree growth

 formed by the repetition of a feature eg farm fields, rows of trees in an orchard, oil storage tanks at a refinery

 - high objects such as towers, chimneys, bridges, or high buildings cast shadows which help you to identify the object

 Cultural Features  - roads and tracks will usually have a light grey tone as they are fairly reflective of light - railways: medium grey - bridges: vary according to construction material

 Natural Features  Water - generally appears dark grey or black since it absorbs much of the light

 Vegetation - most will vary from shades of grey to black

 Soil - bare ground usually has a light colour but the wetter it is, the darker the tone

 Crops - cultivated fields and fallow fields are almost white in tone

 General Guide Spring: sharp, distinct field patterns due to differences in tillage and crop development Summer: dark tones for maturing crops and heavily leafed trees Fall: distinct field patterns because of the various stages of crop development and harvesting Winter: when there is little or no snow cover, tones are generally drab and dull

 See Notes for Interpretation  t2/U02L09.htm t2/U02L09.htm  Homework