CLIMATE. 299 



the Cape of Good Hope. The northern belt is continued into 

 Asia Minor, Palestine, Syria and Persia, and is again manifest 

 in northwestern India; but to eastward is stopped by the in- 

 fluence of the great Himalaya range. The plateau countries 

 beyond, in Central Asia, are extremely arid, largely by 

 reason of their high elevation. 



In Australia the southern arid belt is very strongly defined. 

 In North America, the arid belt is characteristically defined on 

 the Pacific Coast. It embraces all but the southernmost point 

 of the peninsula of Lower California, with about two-thirds 

 of the State of California; thence eastward across Sonora and 

 Arizona to New Mexico and western Texas. But here the 

 influence of the mountain ranges and high plateaus obscures 

 the subtropical belt as such, the arid climate continuing, east 

 of the great Pacific ranges, through Nevada, Utah, Wyoming, 

 Montana, Idaho, and eastern Oregon and Washington nearly 

 to the line of British Columbia on the north, and with gradu- 

 ally decreasing aridity, into Colorado, Kansas, Nebraska, and 

 the Dakotas. 



In South America the rainless seaward slopes of southern 

 Peru and northern Chile indicate the southern arid belt; but 

 here, the great chain of the Andes intervening, the dry pampas 

 of Argentina, and the Gran Chaco of southwestern Brazil, like 

 the Nevada basin, though arid would naturally be referred to 

 the moisture-condensing influence of the Andes chain, under 

 the lee of which they lie. From this cause the region of de- 

 ficient rainfall, which on the western coast ends to northward 

 of Santiago de Chile, is east of the Andes continued much 

 farther poleward, as in North America; reaching into Pata- 

 gonia. 



Utilization of the Arid Belts. While, as already explained, 

 the distribution of the rainfall through the year is nearly as 

 important as its total amount, yet it is evident that even with 

 the minimum of twenty inches of total precipitation as the 

 measure for crop production, a very large proportion of the 

 land of the arid region cannot, even with the most elaborate 

 system of water conservation, be supplied with sufficient water 

 for ordinary crops, and must be otherwise utilized, mainly for 

 pasture purposes. This is rendered practicable to a much 

 greater extent than might be expected, because the rapid transi- 



