WHAT IS A FIELD?
A FIELD IS A REGION OF SPACE THAT HAS A
MEASURABLE QUANTITY AT EVERY POINT
A FIELD MAP IS USED TO REPRESENT
ANY QUANTITY THAT VARIES IN A
REGION OF SPACE
FIELD MAPS
TEMPERATURE
PRESSURE
PRECIPITATION
LINES ON A MAP THAT CONNECT
POINTS OF EQUAL VALUE
ISOTHERMS – LINES OF EQUAL TEMPERATURE
ISOBARS – LINES OF EQUAL PRESSURE
CONTOUR LINES – LINES OF EQUAL ELEVATION
ENERGY SOURCE – REGION OF THE
HIGHEST ENERGY VALUE IN A FIELD
ENERGY SINK – REGION OF THE
LOWEST ENERGY VALUE IN A FIELD
**ENERGY ALWAYS FLOWS FROM AN
ENERGY SOURCE TO AN ENERGY SINK**
DYNAMIC FIELD - A FIELD WHICH CAN CHANGE
STATIC FIELD - A FIELD WHICH REMAINS THE SAME
1.) ISOLINES CONNECT POINTS OF
EQUAL VALUE
2.) VALUES OF ONE SIDE OF AN
ISOLINE ARE LOWER, WHILE ALL VALUES
TO THE OTHER SIDE ARE HIGHER.
3.) ISOLINES NEVER CROSS ONE
ANOTHER
4.) ISOLINES MAY FORM CLOSED LOOPS
5.) ISOLINES NEVER END SO THEY
SHOULD BE DRAWN TO THE EDGE OF THE
MAP, UNLESS THEY FORM A LOOP
6.) ISOLINES TEND TO PARALLEL ONE
ANOTHER
7.) ISOLINES ARE CURVED AND/OR
SMOOTH WITH NO SHARP TURNS OR
CORNERS.
8.) ISOLINES ARE DRAWN ACCORDING
TO A DESIGNATED ISOLINE INTERVAL.
(ON A TOPOGRAPHIC MAP, THIS IS
CALLED THE CONTOUR INTERVAL)
9.) ISOLINES SHOULD ALWAYS BE
DRAWN IN PENCIL FIRST, TO ALLOW
FOR REVISIONS
THE RATE AT WHICH A FIELD VALUE
CHANGES OVER DISTANCE
CHANGE IN FIELD VALUE
GRADIENT =
CHANGE IN DISTANCE
CLASSROOM TEMPERATURES RECORDED IN CLASS
DURING THE WINTER
THE TEMPERATURE
INTERVAL FOR THIS
MAP IS 2ºF
LET’S DRAW
THE LINES!
FRONT
YOUR LINES SHOULD RESEMBLE THE
LINES IN THE DIAGRAM BELOW!
TO CALCULATE THE GRADIENT BETWEEN POINTS A AND B
1.) FIND THE TEMP. DIFFERENCE BETWEEN THE TWO POINTS
2.) MEASURE THE DISTANCE BY MARKING THE END POINTS
ON A PIECE OF PAPER AND THEN COMPARING TO THE SCALE.
PLUG THOSE NUMBERS INTO THE FORMULA
GRADIENT= CHANGE IN FIELD VALUE
CHANGE IN DISTANCE
GRADIENT = 12ºF
11 FT
GRADIENT = 1.1 ºF/ft
NOW LABEL THE ENERGY SOURCE AND
THE ENERGY SINK FOR THIS FIELD
SOURCE
SINK
IS THIS A STATIC OR DYNAMIC FIELD?
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