Earth Fields Fields: Regions of space where there are measurable quantities of a given property at every point. Isoline: connects points of equal value. -Several types of isolines :  Isotherms: connect points of equal temperature

 Isobars: connect points of equal pressure  contour lines: connect points of equal elevation Rules for Isolines: -Lines can’t end in the middle of the map -Each line must connect an equal value and not change -Lines cannot cross each other

TWO MAJOR TYPES OF FIELDS! Scalar Fields- fields that express a magnitude (amount) of something such as temperature, humidity or air pressure Vector Fields- Fields that need both an amount and a direction to be expressed, such as wind velocity, gravitation or magnetism * Over time, all fields will change, therefore field maps are only accurate for a short period of time Example: Earth’s elevation field is changing as the land surfaces erode away or build up.

CONTOUR LINE -LINE THAT CONNECTS EQUAL POINTS OF ELEVATION

CONTOUR INTERVAL THE DIFFERECE IN ELEVATION BETWEEN TWO CONTOUR LINES WHAT IS THE CONTOUR INTERVAL?

RIVER AND STREAM FLOW FLOW THE OPPOSITE WAY THE CONTOUR LINES POINT(BEND) WHAT DIRECTION IS THE STREAM FLOWING? BLUE RIVER

GRADIENT: -”The average slope” The rate of change in field values between two points in a field. Gradient= change in field value change in distance =differences in elevation between A and B(m) distance between A and B (km) -For example, how quickly it takes for an elevation to go from 600ft to 400 ft. Keep in mind that the change can occur quickly(steep) or slow(gradual).

DETERMINES HOW STEEP AN AREA ACTUALLY IS

SAMPLE GRADIENT PROBLEM: - Calculate the average slope of a mountain trail from the 980-meter contour line to the 480-meter contour. The distance between these two elevations measures 4 Kilometers. Gradient= change in field value - change in distance difference in elevation(m) distance between the points(km) 1)980m – 480m 4km 500m 4km 125m/km

Profiles: -Allows you to see a set of contour lines as a “side view” -Makes flat contour lines on paper turn into a 3 dimensional picture of the landscape -Allows you to see which areas on a map are steeper than others

a. Black. Indicates cultural (man-made) features such as buildings and roads, surveyed spot elevations, and all labels. b. Red-Brown. The colors red and brown are combined to identify cultural features, all relief features, non-surveyed spot elevations, and elevation, such as contour lines on red-light readable maps. c. Blue. Identifies hydrography or water features such as lakes, swamps, rivers, and drainage. d. Green. Identifies vegetation with military significance, such as woods, orchards, and vineyards. e. Brown. Identifies all relief features and elevation, such as contours on older edition maps, and cultivated land on red-light readable maps. f. Red. Classifies cultural features, such as populated areas, main roads, and boundaries, on older maps.