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<br /> <br /> <br />. .~ <br />., <br />.;~ <br /> <br />.~ <br /> <br />~~; <br /> <br />alleged to be evaporated and transpired from the irrigated area and <br />entirely lost to Colorado, is precipitated within the Basin and none lost. <br /> <br />The Department of Agriculture in Miscellaneous Publication No. 397, <br />f"H dated July, 19410, Page 3, makes this statement: "The quantity of water <br />b, removed from inland areas through evaporation and transpiration ranges <br />~ from 50 to 95 percent and averages 70 per cent of the precipitation on <br />some areas. Mr. R. Zon, Director of Lake Forest Experiment Station <br />U. S. D. A. in "Forests and Water in the Light of Scientific Investigation", <br />makes the following statement. <br /> <br />"If precipitation over land depended solely on the amount of water brought <br />by prevailing winds directly from the ocean, rainfall would of course be <br />confined to only a narrow belt close to the sea. Not all the water that is <br />precipita.ted, however, is lost from the air current. A large part of it is <br />again evaporated from the land into the atmosphere. Hence the mor.e re~ <br />mote from the ocean the greater is the proportion which evaporation from <br />the landforms of the air moisture. In fact, at certain distances, prac~ <br />tica.1ly all the moisture of the air, or at least as great a part as that <br />formed 9riginally by the water evaporated direct from the ocean. must <br />consist of that obtained by evaporation from the land." Zon makes the <br />further statement "that 78 percent c:ifall the precipitation that falls over <br />the peripheral land area is furnished by the area itself. " <br /> <br />It is alleged by some that most of the precipitation in the Colorado River <br />Basin occurs in the winter and would not be augmented by any evapora- <br />tion frOm land areas. That allegation is not true as 5,0/0 of the total <br />precipitation recorded at stations in Colorado occurs in the six month <br />period April to.September, and 540/0 of the precipitation at Fraser, <br />Coloraclo in the heart of the mountain area occurs during that period. <br /> <br />Your attention is called to Exhibit il3, which shows the a.verage mean <br />ten year 'wind movement from a number of stations scattered over the <br />Basin. On this same map are plotted squares which represent, to scale, <br />the lands now irrigated in the Basin. <br /> <br />Since the. principal source of moisture of major storms in the Basin is <br />the Gulf of California and the Pacific Ocean. this moisture laden air <br />passing over the irrigated areas can pick up any moisture from them <br />and carry it until conditions are favorable for precipitation. Due to <br />the direction of most of the prevailing winds being toward theContinantal <br />Divide &1lcl due to the height of this barrier, few if any of the major storms, <br />as stated before, or the local stormet ever precipitate much moisture On <br />the east side., <br /> <br />~18- <br />