Microbarograph. A Weathertronics, Incorporated (Sacramento, CA), 

 recording aneroid sensor (microbarograph) located in the laboratory building 

 was also used to continuously record atmospheric pressure variation. 



The microbarograph was compared daily with the NWS aneroid barometer, 

 and adjustments were made as necessary. Maintenance of the microbarograph 

 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. 



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. The 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 



Daily and average atmospheric pressure values are presented in Figure 4, 

 and summary statistics are presented in Table 2. 



1025 



1015- 



sz 1010 



CL 



1005- 

 1000- 



995- 

 990- 



Year Mean, mb 



x K1994 1017.5 



o— -01983-94 1016.9 



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



Month 



Figure 4. Daily barometric pressure values with monthly means 



Chapter 2 Meteorology 



