UNIT II. THE WEATHER AND CLIMATE ABOUT US 



In many ways we are affected by the weather. It 

 determines the type of clothing we wear, influences 

 our play, and is one of our most common topics of con- 

 versation. Our food and water supplies are directly 

 affected by the weather, which also plays an important 

 part in our health. 



The world's business, which indirectly affects each 

 of us, is dependent to a great degree upon weather. 

 Many of our crops such as wheat, corn, and cotton 

 depend upon favorable weather; with unfavorable 

 weather conditions the people dependent upon these 

 crops are deprived of their livelihood. Prediction of 

 approaching cold waves and storms helps the farmer 

 and the fruit grower and shipper. Not long ago the 

 prediction of an approaching hurricane by the United 

 States Weather Bureau made it possible for cargoes 

 valued at more than $50,OCO,COO to reach protecting 

 ports safely. Many other forms of business such as the 

 selling of coal, ice, and ice cream are directly de- 

 pendent upon weather and climate for their success 

 or failure. Holders of food concessions in large public 

 parks frequently consult weather reports in order to 

 determine whether the majority of picnickers on a 

 certain day will purchase "hot dogs" or ice cream. 



Weather prediction has reached a high degree of 

 certainty. Knowledge gained through many years of 

 careful observation and results obtained in exploring 

 the upper atmosphere have made this possible. Ex- 

 peditions to Greenland and other parts of the North, 

 together with Admiral Byrd's Antarctic expedition, 

 have provided scientists with new material which may 

 aid in solving many puzzling problems of storm pre- 

 diction. 



Weather prediction is so important in industry, 

 business, navigation, and our immediate everyday 

 lives that the government maintains a large organiza- 

 tion to care for it. This organization has its headquar- 

 ters at Washington, D.C., and is known as the United 

 States Weather Bureau. The weather forecasts are 

 based upon observations of local weather from more 

 than three hundred stations scattered over the coun- 

 try. Observations are also received from Alaska, Can- 

 ada, Mexico, and ships at sea. On the basis of the 

 observations made, daily weather maps and bulle- 

 tins are mailed from a hundred or more distributing 

 points. These maps reach nearly 100,000 addresses 

 daily, which represent only a small fraction of all the 

 people receiving benefit from this remarkable service. 



For centuries, in every land, the weather has been 

 such an absorbing topic that many quaint weather 

 rimes and sayings have grown up. Some of these are 

 scientifically accurate, while many have not the slight- 

 est element of truth in them. These sayings, com- 



monly called weather lore, are fascinating, and it is 

 hoped that you will find time during this study to 

 acquaint yourself with many of them and to determine 

 their accuracy from a scientific viewpoint. 



In this introduction the many ways in which 

 weather affects you have been pointed out. In the 

 study of the unit you will learn more interesting 

 things about weather and the laws and principles of 

 science which control it. 



How many of these questions about the weather 

 can you answer? In your notebook write as many of 

 the answers as you can. 



1. How accurate are the predictions made by the 

 U. S. Weather Bureau? Cut from the paper each day 

 for a period of four days the local prediction of the 

 weather. Paste this neatly in your notebook and date 

 it. Carefully observe the weather for each day and 

 make a note as to its accuracy. 



2. In what ways has the climate of your locality de- 

 termined the mode of living there? 



3. List some of the factors which you regard as im- 

 portant in predicting the weather. 



4. Show as many ways as you can in which the 

 climates of North America have determined the modes 

 of living of the various tribes of American Indians. 



5. Make a drawing representing the earth as a circle 

 about two inches in diameter. On this place the vari- 

 ous climate belts of the earth and name the lines, 

 which divide them. 



6. What causes the climate of California to be so 

 pleasant when other parts of the country in the same 

 latitude may be having extremely cold weather? 



7. How do you acount for the fact that tornadoes 

 seem to be especially numerous in the Middle West? 



8. What causes a thunderstorm? 



9. List as many ways as you can in which a person 

 living in New York lives differently from one in Lima,- 

 Peru, because of weather or climate. 



10. In what ways is weather prediction of import- 

 ance? 



11. What are some of the recent developments in 

 weather forecasting? 



12. Show how weather forecasting is becoming in- 

 creasingly important to aviation. 



13. Do you think that the recent stratosphere flights 

 might add anything to our knowledge of weather and 

 aid the accurate prediction of the weather? Explain 

 your answer. 



14. Why do you think Admiral Byrd took trained 

 weather forecasters with him on both of his expedi- 

 tions into the Antarctic? Of what value could the 

 knowledge gained by these scientists be for weather 

 forecasting in general? 



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