30 March, 2002

Weather: Sunny
High 18
Low -12

Saturday Rounds at Poker Flat

Three teachers from Martin's snow and ice course joined us for our usual Saturday trip to Poker Flat. In addition to measurements from four ponds, we do two transects (land and woods) and ice thickness. Research assistant, Craig is comparing heat flow results from these two additional transects for his senior thesis.

The Science Behind Temperature Gradient, continued

Are you ready for the next step? Remember, all we need are three things: snow depth (Zs), surface temperature (Ts) and base

temperature (Tb). The formula is Ts-Tb/Zs. What are the temperature gradient results for March 27th, 29th, and 30th? See tomorrow for answers.

Jalpertia pond

March 27
Mean Ts: ñ5.0 C
Mean Tb: ñ 2.2 C
Mean Zs: 0.278 m

March 29
Mean Ts: -16.25 C
Mean Tb: -3.97 C
Mean Zs: 0.277 m

March 30
Mean Ts: -13.32 C
Mean Tb: -4.86
Mean Zs: 0.793 m

1. Craig, research assistant takes his turn. __________________________________________________ Do You Yahoo!? Yahoo! Greetings - send holiday greetings for Easter, Passover http://greetings.yahoo.com/