The area designations set forth in this report are 

 arbitrary andj in general, principally geographical subdivisions. 

 When additional years of data become available, these area break- 

 downs must be reconsidered. Analysis of the records of individual 

 stations to date indicates as much variability in evaporation be- 

 tween adjacent stations, within any one area, as between areas. 

 This variability is shoim in Tables 3 and 4, in which all of the 

 stations located on irrigated pasture in 1959 and 196O were arranged 

 in order of decreasing evaporation rate by month. The same was done 

 for the 1959 and 196O dryland stations. On the basis of these data. 

 It is concluded that no definite segregation of the stations into 

 areas of uniform evaporation Is possible. 



A general pattern has been discerned with certain of the 

 stations tending to be high and others low. There are indications 

 that, for stations having similar environments immediately sur- 

 rounding the site, adjacent dryland areas exert climatic influences 

 and affect evaporation rates at the station site. 



This factor is being given further consideration In rela- 

 tion to the agrocllmatlc stations currently in operation. Efforts 

 are being made to standardize conditions where pan and atmometer 

 data are collected. Insofar as possible, large, well-irrigated 

 pastures providing nearly 100 percent ground cover are being se- 

 lected as sites for agrocllmatlc stations. As data are obtained 

 under similar environmental conditions, more conclusive compari- 

 sons may be made. It may be fo\jnd that there are small differences 

 In monthly evaporative rates between different agricultural areas 

 of the State, and that the length of growing season is the most im- 

 portant factor affecting seasonal evapotranspiration in Inland areas. 



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