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4 April, 2002

Snowboard case, camera tripod and fiber optics!!!! It sounds like a setup for the X-games on ESPN. However, it's science…..in the cold…

Wrapped inside a blanket tucked in a snowboard bag lies the camera tripod. The snowboard bag also holds the fiber optic cable holder. The camera tripod is set up on the snowpack and checked to see if it is level. The metal bar that sets tightly on top the tripod is precisely placed and now we are ready for the delicate material…. The fiber optics.

The black fiber-optic cable and metric probe are carefully stored in a wooden box packed with foam. It is gently taken out of the box and the cable is unwrapped with care. The fiber-optic cable can be easily broken, so it is important to be careful. The black fiber-optic cable travels down the metric probe and is attached to a sensor at the bottom of the probe. The end of the fiber- optic cable is then attached to fiber-optic converter box that attaches to the computer inside the heated sled.

Are you confused yet? Are you wondering what we are doing? What is all of this technical setup for? It's not the x-games or a photo shoot. This measurement is called the light attenuation probe, which measures the amount of light that penetrates into the snowpack. There are more fine details on the operation of the light attenuation probe.

One person sits outside in the cold and, using the tripod, lowers the sensor into the snow. It is important to have the tripod and entire setup level. This person is talking to the WIZARD inside the heated sled. I always feel like I am talking to the Wizard of Oz - the wizard who sets behind the curtain controlling the world outside. Our wizard sits in the heated sled running the computer program that computes the light attenuation. The cold person outside lowers the probe down, centimeter by centimeter into the snowpack. After a new depth is reached, the wizard hits some buttons on the computer and the data are recorded. The sensor at the end of the metric probe measures the amount of light and sends the signal up the fiber optic cable and transmits the light intensity into the computer.

The wizard and the cold person…… The wizard computes in the heated sled while the cold person fumbles with mittens and bundles of clothes handling the delicate instrument. Science measurements are collected and stored!

More light lessons later!!!

SO WHERE IS MRS. CHEUVRONT????? LET'S PLOT!!! Latitude: 66.70197 degrees North Longitude: 160.01095 degrees West

Our departure from Selawik brought us outside to the sunny, snow, cold, world. It felt good to be out on the trail once again…. On the move. The trail was good for traveling and the base of the Brooks Range stayed on the horizon. It was out there… the fabulous Brooks Range… our soon to be future. Three sites were completed today. The sun energized our work. We traveled on heading north on the trail to Ambler. We traveled mostly on open tundra and shrub areas. The deeper snow gives us clues of our farther travels north. After departing from the open land, trees were spotted for the first time in many days. Spruce trees and even some Birch trees were standing along a riverbank. A large moose with her calf stood along the riverbank grazing amongst the bushes. The moose and her young had greeted us to our home for the evening. A shelter cabin along the trail to Ambler would be our home. A simple cabin, but warm and cozy details our evening.

Temperature Max: -6 degrees Celsius Temperature Min: -15 degrees Celsius


Running the Light Attenuation Probe.


Looking down the 100 meter line. This is how the snow looks after we finish our measurements. The snow scuptures are from digging the snow pits!


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