Page 270 - NS-2 Textbook

METEOROLOGY 265

Upper Burma around Mandalay is often 4 to 6 inches 3. A. What two motions of Earth affect the weather?
thick along roads and in villages. B. Which of these motions causes the major wind
belts?
4. How does the Coriolis effect cause winds to deflect
WINDS AND THE BEAUFORT WIND SCALE
in the Northern and Southern Hemispheres?
Meteorologists must always be aware of wind velocity 5. A. How does ahnospheric pressUl'e affect the pri-
and wind direction. Wind speed is always given in knots, mary wind belts?
according to international agreement. The instrument B. What are the principal high-pressure belts on
used to measure wind speed is called an allemomeler. Earth's surface?
Wind blows into metal cups, which are attached to arms. 6. What determines the directional name of a wind?
The whirling cups turn a spindle, the speed of which is 7. Explain each of the world's prevailing wind and
calibrated into wind speed. A vane atop the anemometer pressUl'e belts.
aligns itself with the direction of the wind. A dial on the 8. A. What movement of Earth causes the seasons?
instrument readout indicates the apparent wind velocity B. What is meant by Earth's "inclination"?
and direction. 9. What names are given to the 23.5 degrees north and
In addition to wind-measuring equipment, the Beau- 23.5 degrees south latitude lines?
fort Wind Scale with Correlative Sea Disturbance Scale 10. What are the principal causes of secondary wind cir-
can also be used to estimate wind speed. This scale is culation?
based on careful observation of sea conditions. Admiral 11. What is the effect of the geography of the continents
Sir Francis Beaufort of the British Royal Navy developed and seas on the primary wind belts in the Northern
the scale in 1805 to estimate wind speeds from their effect Hemisphere?
on sails. His table numbered the winds from 1 to 12, in 12. How does air "act" in a high-pressure area?
order of increasing severity. It compared them to the Sea 13. Over what countries in the Northern Hemisphere do
Disturbance Scale, which describes sea state and mean "permanentU high-pressure areas exist?
height of waves on a scale of 1 to 9. Descriptive terms 14. A. Where do the principal low-pressure areas exist
identify the winds and their counterpart waves. The on Earth?
Beaufort Wind Scale enables the shipboard weatherman B. Where do seasonal lows usually develop in the
or sailor to estimate wind speeds merely by looking at United States?
the sea state and then comparing the two scales. 15. A. What are the most famous mountain winds, and
By convention, wind direction is specified according where do they blow?
to the compass direction or geographic point of origin B. W11at type of weather do these winds bring?
from which the wind blows. III 16. W11at valley wind is of particular concern to the
Sixth Fleet?
17. A. W11at are monsoon winds, and where are they
most common?
CRITICAL THINKING
B. Describe the generation of the southwest and
1. Research the factors that forecasters use to predict northeast monsoons.
the frequency of hurricanes occurring in the Atlantic 18. A. What instrument is used to meaSUl'e wind ve-
and Pacific basins prior to the start of each hurricane locity?
season. B. Wllat dialed instrument indicates wind speed and
2. Investigate the names and locations of the most im- direction to the ship's bridge watch and navigator?
portant weather satellites currently in use for weather 19. A. What is the Beaufort Wind Scale?
forecasting. B. How is the Correlative Sea Disturbance Scale
3. List the major preparations a homeowner should used with the Beaufort Wind Scale?
make when a hurricane is forecasted to strike.
4. How can the power of wind be harnessed to provide Vocabulary
a partial solution to the energy crisis?
gradient Tropic of Capricom
high, low migratory lows
anticyclone Chinook winds
Study Guide Questions
doldrums foehn winds
1. A. What is a simple definition of wind? h'ade \J\Tinds Santa Anas (winds)
B. Upon what does the strength of wind depend? Horse Latihldes monsoon
2. What are the three primary wind belts in the North- prevailing westerlies anemometer
ern Hemisphere? Beaufort Wind Scale Tropic of Cancer