14 August, 2001

Sound Off

Tuesday, 14 August 2001

Valkommen!

Life on Board

Volleyball is a game that can be enjoyed by anyone, anytime, anywhere. Even at 88 degrees north! Michael Jensen brought a WILSON outdoor volleyball with him from Colorado and someone found a big cargo net. Of course there are poles around the ship, and a bright pink length of rope for the court outline. Renamed "Ice Volley", we played hard from about 9 pm until midnight, then quit because we were tired, not because it got dark (that never changes). We played 6-on-6 with 4 rotating in on each side. Even those who didn't want to play came out on the deck or onto the snow to watch these intense and closely matched teams battle it out in the snow (well, OK, we didn't really even keep score). Snow makes a great playing surface because you can dive and roll like in sand, but you don't get all gritty, there are interesting obstacles on your court like melt ponds and ice blocks, and you can play really hard and not get too hot, in fact, you want to play as hard as you can to stay warm. I think this should be an official sport in the Snolympics! Side out!

Where Are We Now?

It was better weather today than we have had lately. It was mostly cloudy with the sun breaking through every once in awhile, long enough to run outside and turn your face to the warmth for a moment. Fog came up with light snow about 1:30 pm but the sun still managed to hazily shine through. Our coordinates at 10 pm were 88o22' N/1o59' W, still drifting a bit south and a bit west.

Scientists at Work

Anytime you go outside the ship, you hear, "beep.beep.beep.beep" coming from the ice. No, it is not a submarine coming to spy on us. No, it is not the microwave oven. The origin of these beeps is three large white boxes out at one of the ice camps near two small red huts. These white cubes are called Doppler and Mono SODARs, and what you see are the housings for some really big speakers. Scott Abbott from NOAA in Boulder, Colorado, points the two Doppler SODARs in different directions and they send out sound waves with a frequency of about 1800 Hertz. The mono SODAR sends out a frequency of about 1380 Hertz. These sound waves go up into the atmosphere and reflect back down when they encounter different densities of air parcticles. These density differences are caused by changes in temperature, pressure, or humidity in the various air masses interacting above the ice. The lower the frequency, the higher up into the atmosphere the sound wave will penetrate. Inside the cube, pointing up at the sky, there are instruments for transmitting the sound and also receiving the reflected signal. The received signal is sent into the computer inside the red huts where it is logged and interpreted, producing a kind of picture of the different air masses in the atmosphere.

The Doppler cubes can also measure wind speed and direction using, you guessed it, Doppler shifts in the reflected signal. You are hearing a Doppler shift when a train goes by and the sound of the whistle changes as it passes by. The same principle is used here because when the wind is going away from the sound wave, the return signal is shifted to a lower frequency and when the wind is going toward the Doppler cube, the return signal is shifted to a higher frequency. Anyway, the computer can interpret all of this and uses some fancy vector calculations from both cubes to determine wind speed and direction. All of this information is used by the scientists to figure out what is going on in the atmosphere so they can determine how parcticles are transported around the world.

Vi ses! (See you later!)

From Deck 4 on the Icebreaker Oden, drifting southwest, but still north of 88, Dena Rosenberger

Ice Volley at midnight!

The SODAR system. Since this picture was taken, the pair of big white cubes has been painted with black dots to look like dice...pretty funny out on the ice!