WEATHER AND CLIMATE 



73 



3. Repeat these observations for one week at a time, and 

 at about the same dates every calendar month throughout 

 a school year. Transfer the "averages" for each week of 

 observation to a second table as below. Only the data by 

 months need be preserved in the notebooks. 



(etc., for the whole school year.) 



4. With practically the same amount of heat (and light) 

 getting through the box at different hours, what is the 



SUN'S PAYS 



REACHING EARTH SUN'S RAYS REACHING EARTH IN 

 AT NOON FROM AFTEROON WHEN SUN IS LOW IN 

 NEARLY ABOVE 



SURFACE OF THE EARTH 



FIG. 32. Difference in heat intensity of sunlight at different degrees of 



obliquity. 



relation between the area covered by the beam of sunlight 

 and the heating effect of that same beam ? 



5. State what is noted in the monthly averages concern- 

 ing changes in heat intensity (a) through the day ; (6) from 

 month to month by seasons. 



6. State the relation apparent between obliquity of rays 

 and seasonal changes. Account for this. 



