Ch- 7 Using Maps 1 K (What I know) W (Want to know) L (What I learned) Warm up- take out a piece of paper and do the “K” and the “W” for the above topic.

California State Standards – Ch. 7 I&E 1h – Read and interpret topographic and geologic maps

Ch 7 Using Maps 1 Main Ideas Details Why do we use maps? To help us find out how to get to places To help us see where geographic features of our Earth are. To show us our Earth on a flat surface To help us learn more about our Earth

Ch 7 Using Maps 2 Main Ideas Details Unfortunately, a flat map of a curved surface is distorted. Maps can be used for many things. The most accurate map of the Earth is on a globe.

Ch 7 Using Maps 3 Main Ideas Details Mercator projection- Mercator – shows true direction in straight lines but distorts distance in high latitudes. Types of maps Different types of maps help minimize distortion of shape, distance or direction.

Ch 7 Using Maps 4 Main Ideas Details Gnomonic projection- Gnomonic- good for plotting shortest distance between two points. Direction and distance is distorted. Types of maps

Ch 7 Using Maps 5 Main Ideas Details Polyconic projection- Polyconic- is a more accurate representation and is useful in making topographic maps. Types of maps

Ch 7 Using Maps 7 Main Ideas Details Latitude & Longitude Latitude- imaginary lines (on earth) that run East-West and measure North-South. Begin at the equator and runs to the poles. Maximum degrees = 90. Latitude lines are called parallels Latitude lines are called parallels.

Ch 7 Using Maps 8 Main Ideas Details Latitude & Longitude Longitude – imaginary lines that run North-South and measure East- West. Begin at the Prime Meridian = 0º. Max degrees = 180º Max degrees = 180º meridians

Ch 7 Using Maps 9 Main Ideas Details Map Scales Map scales- tell us how the map compares in size to the Earth’s surface. This map scale is a ratio of distance on the map to distance on Earth. 1:24,000 1:100,000 1 inch =.4 mile1 inch = 1.5 miles 7.5 minutes latitude 7.5 minutes longitude 54,000 contiguous U.S.

1:100,000 1:50,000 1:24,000

Ch 7 Using Maps 10 Main Ideas Details Topographic Maps Topographic Maps Topographic Maps show landforms and relief or elevations. Contour lines- are lines on a topo map that connect points of equal elevations. The contour interval is the change of elevation between two contour lines.

Ch 7 Using Maps 11 Main Ideas Details Reading a topo map All maps show directions in some way. Meridians and parallels show direction. Magnetic declination- sometimes maps have arrows that point toward the North Pole or the magnetic North Pole. The difference between true North and magnetic North is the magnetic declination.

Ch 7 Using Maps 12 Main Ideas Details Reading a contour map 1.Contour lines of one elevation never crosses a contour line of another elevation. 2.Closely spaced contour lines represent a steep slope. Contour lines spaced far apart represent a gentle slope. 3.Contour lines that cross a valley are V shaped. The V points upstream. (uphill) 4.The tops of hills are often shown as closed loops or circles.

Ch 7 Using Maps 13 Main Ideas Details

Details Remote sensing methods allow mapmakers to produce accurate maps of many places on Earth. G.P.S Global Positioning System uses satellites to help find positions on the Earth. Ch 7 Using Maps 14 Creating your own map-

Ch 7 Using Maps 15 Main Ideas Details Summary Write your 3-5 sentence summary of these notes. Highlight the important parts of your notes.