SUMMER AND WINTER EFFECTS ALONG A SHORE 243 



does not show appreciable changes of temperature except 

 with the changing seasons. At a very few feet below the 

 surface the soil maintains a steady temperature summer and 

 winter. 



Surfaces that absorb heat rapidly also radiate it rapidly. 

 A large percentage of the heat that the soil has absorbed 

 during the day is given out to the atmosphere at night. 

 But the water, slowly storing heat during the warm months 

 and just as slowly giving it out during the cold months, 

 has a steadying effect upon the climate of the land adjoining. 

 On some islands of the sea, the range of temperature through- 

 out the year is almost imperceptible, whereas in the interior 

 of continents the average temperature of some of the summer 

 months is more than a hundred degrees higher than that 

 of some of the winter months. 



Day and Night Effects along a Shore. In the summer, 

 the morning sun heats the soil increasingly until, by reflec- 

 tion and radiation from the land surface, the atmosphere 

 above it is highly heated and expanded. The cooler air 

 flows in from the lake or sea and displaces the lighter warm 

 air. If the sun continues to shine, this landward breeze 

 persists until late in the afternoon ; but its effect is never 

 felt many miles inland. At night when the rapidly cooling 

 soil reaches a temperature below that of the water, the 

 direction of the breeze is reversed. 



Summer and Winter Effects along a Shore. During 

 the summer in warm climates, water is heated much less 

 rapidly than the moist air above it and so it absorbs heat 

 from the air day and night. This cools the atmosphere, 

 and cooled air currents from above the water temper the heat 

 of the adjoining land. 



