Mrs. Beals (my mother, not my wife!) 5th grade class from Bitterroot Elementary in Billings, Montana sent me to Greenland with a plan. They were interested in finding out how the length of a shadow in Billings compares to the length of a shadow at the top of the ice sheet in Greenland.
I have followed their instructions as written (see them here: http://www.polartrec.com/node/3888) and have produced a graph according to how they wanted it constructed.
I placed a pencil in the snow and measured the length of the shadow at 10:00, 12:30pm, and 3:00pm.
Results:
10:00am = 23 cm
12:30pm= 18 cm
3:00pm= 20 cm
You can compare data on the graph links below or download the .pdf files at the very end of this post:
Graph with YOUR (Billings, MT) data and MY (Summit, Greenland) data: http://nces.ed.gov/nceskids/createagraph/default.aspx?ID=6a3f17540ef645daa54977788b64a249
I also decided to do your experiment all through the night so you could see how long the shadow length from the sun is in the middle of the night up here!
Graph with measurements from all day and all NIGHT!: http://nces.ed.gov/nceskids/createagraph/default.aspx?ID=6a3f17540ef645daa54977788b64a249
So, Mrs. Beals class, what do you think? Did I perform your experiment correctly? How do your measurements compare to my measurements. Was your prediction correct? Why was the shadow so long in the middle of the night?
NOTE: Your experiment got all of the scientists thinking. We decided to take your idea and turn it into a science/art project (you might call it “extra credit”). We placed a large bamboo pole out in the snow. At the start of each hour we placed a shorter bamboo pole where then end of the shadow from the LONG bamboo pole was. We are still working on it because even though the sun is up 24 hours a day, we sometimes have clouds (plus sometimes we sleep for a few hours in the middle of the night and aren’t able to get a pole stuck into the end of the shadow). When we are done we will have a HUGE outdoor “Sundial” so we can tell the time just by looking at the shadow from the long bamboo pole!
I will keep you all updated on the “extra credit” project we are working on and post pictures.
THANK YOU for your great ideas and hard work!
Stay Warm!!
PS. The day after I finished your experiment a snow storm blew through camp and now the PolarTREC pencil is buried deep in the snow!