As the sun moves across the sky the shadow that an object creates by blocking the sun's rays changes shape and moves. At local noon (the time when the sun is highest) the shadow is at its shortest and points in a particular direction. The shortest length of the shadow, and the time at which the shadow is shortest can be used to determine latitude and longitude of the location where the experiment is being carried out. (See reverse)

In this exercise a member of the group should stand straight up on a horizontal section of beach and have another member of the group trace the shape of their shadow in the sand. They should have their shadow traced at regular intervals (every 15 minutes) between 12 noon and 2:00 pm. (Note: at La Push at this time of year local noon is actually closer to 1:00 pm then 12:00). There is no need for the person being drawn to stand in one place the entire time, as long as they return to the same place every 15 minutes and strike the same pose for their shadow to be drawn.

Measure and record in your lab notebook the height of the person whose shadow is being drawn, the length of each shadow drawn and the time the measurement is made. Use the group's compass to determine the direction of the shadow when it is shortest. Record this in your lab notebook. On our return we will plot length of shadow versus time and use this curve to determine the latitude and longitude at La Push.

Take a photograph of the shadow drawing when you are finished.

Record your latitude and longitude using the GPS. Walk down the beach at least 100 m and again record your latitude and longitude using the GPS. Now with the record distance you walked and the angle measurements you should be able to determine the circumference of the earth. Note your calculations will be significantly simplified if you keep longitude constant by walking due north or due south. Now find the radius and volume of the earth.

Walk from the base of a tree to a position where you can have a good view of the base of the tree. Measure this distance. Use a clinometer to measure the angle of inclination from the horizontal up to the top of the tree. From the angle of inclination and the distance to the tree you should be able to determine the height of the tree. With this information estimate the volume of wood in the tree.