Читать книгу Cornell Nature-Study Leaflets - New York State College of Agriculture - Страница 43

1. What causes snow?

2. At what temperature do snow crystals form?

3. How do the clouds appear before a snow storm?

4. What is the temperature of the air before the storm?

5. What is the direction of the wind before the storm?

6. Does the storm come from the same direction as the wind?

7. What are the conditions of the wind and temperature when the snow crystals are most perfect in form?

8. What are these conditions when the snow crystals are matted together in great flakes?

9. What are these conditions when the snow crystals appear sharp and needle-like?

10. Are the snow crystals of the same storm similar in structure and decoration?

11. What is the difference in structure between a snowflake and a hail stone?

12. What is sleet?

13. What is the difference between hoar frost and snow?

14. Does the temperature rise or fall during a snow storm?

15. Is it colder or warmer after a snow storm has passed than it was before it began?

16. What are the conditions of weather which cause a blizzard?

17. Why does a covering of snow prevent the ground from freezing so severely as it would if bare?

18. Why is snow a bad conductor of heat?

19. Pack snow in a quart cup until it is full and let it melt; then tell how full the cup is of water. What do you infer from this?

20. Have you ever observed the grass to be green beneath snow drifts? Tell why.

21. Does snow evaporate as well as melt?

22. How does snow benefit the farmer and the fruit grower?

23. Do the snow storms in your locality come from one general direction all winter?