Glaciers

5. during the ice age there are warmer periods
9. lakes when a narrow lake occupies the floor of a valley and when ribbon lakes are linked
12. steep sided mountain eroded by cirques
13. ice sheets covered huge areas of the earth
15. ice begins to move slowly to lowland areas under the influence of gravity
16. large hollow on the diode of a mountain with three steep sides. It is the birthplace of a glacier

1. small tributary valley that hangs above main glaciated valley
2. when ice moves forward it plucks large chunks out of the ground
3. weather conditions in an area measured over a long period
4. glaciers melted while others joined together
6. interlocking spur whose head was eroded based glacier moved through the valley
7. v-shaped valley straightened and flattened by glacier to become u-shaped
8. narrow steep sided ridge between two cirques
10. as rocks move they scrape and smooth the surface
11. lake inside a cirque
14. great river of ice