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

TEMPERATURE

PRESSURE

PRECIPITATION

FIELD MAPS

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

7.) ISOLINES ARE CURVED AND/OR SMOOTH WITH NO SHARP TURNS OR CORNERS.

6.) ISOLINES TEND TO PARALLEL ONE ANOTHER

5.) ISOLINES NEVER END SO THEY SHOULD BE DRAWN TO THE EDGE OF THE MAP, UNLESS THEY FORM A LOOP

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

GRADIENT =CHANGE IN FIELD VALUECHANGE IN DISTANCE

CLASSROOM TEMPERATURES RECORDED IN CLASS DURING THE WINTER

FRONT

THE TEMPERATURE INTERVAL FOR THIS MAP IS 2ºF

LET’S DRAW THE LINES!

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 VALUECHANGE IN DISTANCE

GRADIENT = 12ºF16 FT

GRADIENT =

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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