25.0- 



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a: 





UJ 



a. 



10.0- 



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oc 



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YEAR MEAN/C 



x 86 16.5 

 o 83-86 16.0 



JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 

 MONTH 

 Figure 4. Mean monthly air temperatures 



15. Microbarograph . A Weathertronics, Inc. (Sacramento, Calif.), 

 recording aneroid sensor (microbarograph) located in the laboratory building 

 also was used to continuously record atmospheric pressure variation. 



16. The microbarograph was compared daily with the NWS aneroid barom- 

 eter, and adjustments were made as necessary. Maintenance of the microbaro- 

 graph consisted of inking the pen, changing the chart paper, and winding the 

 clock every 7 days. During the summer, a meteorologist from the NWS checked 

 and verified the operation of the barometer. 



17. The microbarograph was read and inspected daily using the following 

 procedure: 



a. The pen was zeroed (where applicable) . 



b. The chart time was checked and corrected, if necessary. 



c. Daily reading was marked on the chart for reference. 



d. The starting and ending chart times were recorded, as necessary. 

 e_. New charts were installed when needed. 



Results 



18. Daily atmospheric pressure values are presented in Figure 5, and 

 summary statistics are presented in Table 2 and Figure 6. 



11 



