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"Animations " (Again, if clicking on the link doesn't work, try the right button click and open it into a new tab.) 1) Looking at fig. 12.3, where is snow occurring, and in what direction does the ice sheet move? 2) Looking at fig. 12.6, does the glacier advance during summer? 3) Again referring to figure 12.6, does the ice in the glacier move during the summer? 4) Again referring to figure 12.6, during what season does snow and firn cover the zone of ablation? 5) Again referring to figure 12.6, what happens to the zone of ablation during the summer? 6) Referring to figure 12.8, looking at the cross-section of a glacier, where does Ice move fastest? 7) Referring to figure 12.9, in what two areas do crevasses open up as the ice in the glacier moves forward? Here is an animation of how terminal and recessional moraines: "Moraine formation animation" 8) Debris from a glacier is transported to its terminus like a conveyor belt, even when it is receding, which allows for formation of moraines. How are recessional moraines different from terminal moraines? (As far as you can tell from this animation!) After clicking on the following link, click "Run Now" to play the interactive. You may have some issues with running it, with changes to the server this year, but watch for the little warnings about downloads, etc. The red "x" in the upper right below your tool bar, etc. and follow through. "phet simulation Take several minutes to "play" with the controls, changing snowfall, temperature, etc. and what you can view. Drag and use tools to see what you can accomplish with them. After several minutes of observing, perform the changes, then answer the following. A) Increase snowfall to cause the glacier to advance. B) Once the glacier has advanced further downslope, click "Set to steady state". Allow it to stay in this form for 5 minutes and observe what happens. 9) Does the ice ever stop flowing forward? 10) Does the glacier continue to advance while in a steady state? 11) What happens to the glacier if you set the snowfall to zero? If snowfall is zero, is the glacier affected by setting temperature lower? Click the tab for "Advanced". Change the settings so that the glacier model descends down the valley somewhat, then press "set to steady state". In the box listed as "graphs Click to turn on "Glacier length vs time", glacial budget vs elevation, and air temperature vs elevation. Allow 500 years to pass, then change the air temperature to something colder. 12) What happens to the glacier length? 13) Does the glacier change thickness? (use the calipers to measure thickness) 14) What happens to the glaciers equilibrium line? 15) Use the meter tool to compare the ablation rate at the terminus (should be different for everyone!) with the ablation rate near the head (beginning) of the glacier. 16) What happens to the glacier if you reduce snowfall slightly? 17) What depositional feature was left behind after you reduced snowfall in #16? Maneuver through the following website to answer the questions below. The control marked "Glacier type" combined with overview and model should help. "Glacier formation interactive! Glacier types " 18) What is the key to building glaciers anywhere? 19) North America 18,000 years ago was covered by ice sheets how thick? 20) What might happen to ALL glaciers by the end of the 21st Century? 21) In what types of areas are Alpine glaciers found? 22) What are the two types of Alpine glaciers which may be found? 23) Explain the difference between an ice cap and an ice sheet. 24) How do tidewater glaciers form? 25) How do striations form? "Glacier formation interactive! 3 animations, stationary, receding, and advancing " Make sure you click on the "next view" arrow at the bottom right side of the page until you have seen all three flash animations. Excellent way to understand the components of glacial advance and retreat! "Milankovitch explanation. " Make sure you click on the "next view" arrow at the bottom right side of the page until you have seen all three flash animations. Excellent way to understand the Milankovitch theory components! |
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