*4« 



YffiY EASTERLY VJINDS ? 



(TfhGn the air over a large area in the United States becomes heated, 

 there is developed a low pressure urea which tends to move toward the east 

 due to the motion of the earth* This often brin{;s an east wind, and rain. 

 Director H. A. Bostrora of the Essex County Agricultural School gave this 

 further explanation of the occurrence of east winds, at a recent twilight 

 Eieeting,) 



"Matters of lari^e economic importroice, or having very much bearing 

 upon our personal comfort, sometii.ies seen to rest upon comparatively 

 insignificont things. Take for example the light easterly winds which 

 seem to dominate the daily climate in the spring and early sumiaer months 

 along our shore. Often we v/ish there vrere not so much of itj other times 

 we are exceedingly glad for the light breeze that penetrates, sometimes a 

 mile or two, sometimes a t;ood many miles inland, to prevent what would 

 otherwise be an unbearably hot day, 



"Yvhen one measures the amount of heat v;hich is required to raise the 

 temperature of the various kinds of materials, -me finds that it takes a 

 great deal more heat to warm a unit of water through one unit change of 

 temperature tluai it does any ■-•ther of the comi.ion substances, such as rock, 

 soil, wood, etc. Said in another way, this means that the temperature of 

 Icaid areas will rise more rapidly from a given wTiount of the sun's heat than 

 will the temperature over the ocean. Consequently, the air over the land 

 areas, war:.is, expands, and rises more rapidly than it does over large water 

 areas, which creates a nove:.iont of the cooler air from over the ocean imvard 

 over the land. The difference may be slight, creating -July a very light 

 breeze, felt only along the shore, or there nay be enough difference to 

 cause the air to move inland a considerable number of miles, 



"In weather, no such siiaplc explanation is entirely correct. To quote 

 the Agricultural Yearbook for l94tl (Climate .vrid Man): 'It is more correct 

 to emphasize that the upper layers of the cean are nearly always in a 

 state of violent stirring, whereby heat losses or heat gains occurring at 

 the sea surfo.ce are distributed through the large volumes of water. This 

 mixing process sharply reduces the temperature contrasts between d ay and 

 night and between winter osid summer. In the ground there is no turbulent 

 redistribution of heat and the effect of molecular heat conduction is 

 very slight. Thus violent c.^ntrasts between day and night are created 

 (inlfoid) '• 



"The vj-riter thus points out that sharper contrasts in temperature are 

 bound to occur over laaid areas than over the water. The ultimate effect is 

 a sharper, quicker rise in temperature over land area- thsoi over the v/ater, 

 resulting in the cooler air fr-'-m the water moving in towards the warmer 

 inland areas, 



"Vt'hen we as students sat in a class in physics and studici the specific 

 heat of solids, liquids, and gases, most of us found it pretty dry material 

 and we didn't care whether water or iron or stone or some other substiuice had 



