Examination

Snow in Northern European Environment -EU course

1-8 March 2002

Rovaniemi and Kilpisjärvi

Lecturers and topics:

1. Thomas Zwinger: Avalanche fluid dynamics
2. Regina Sterr: Avalanches
3. Matti Leppäranta: Snow on lake ice
4. Hardy Granberg: Snow physics
5. Carl Bøggild: Water flow in snow
6. Karin Helmens: Glacial history of Scandinavia

Questions you find in the following pages.

Please, write your answer next to the question in the same side of the paper.

Snow on floating ice

snow

slush

snow-ice

congelation ice

In water bodies a large amount of snow transforms to snow-ice

Questions:

a) What is the Stefan´s law for lake ice growth?

b) What are mechanisms for snow-ice formation?

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* * * * * => 000000
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t1 t2

The sketch shows the evolution of snow grains.

Question:

Please explain the mechanisms which result in this

rounding of crystals.

The avalanche illustrated above has been initiated on a mountain slope.

Question:

Please explain the conditions which favour the start of avalanches.

The figure above shows the avalanche in motion.

Question:

Please explain the differences on flow in each part of the avalanche.

Describe the landscape in fig B and explain how it did form

The figure above shows water flow at an early stage in a snow pack.

Question:

Please explain the mechanisms which results in the different flow regimes.