readings, the probe was installed 3 m above ground inside a "coolie hat" to 
shade it from direct sun, yet provide proper ventilation. 
Results 
13. Daily and average air temperature values are tabulated in Table 2 
and shown in Figure 3. 
Atmospheric Pressure 
Measurement instruments 
14. Electronic atmospheric pressure sensor. Atmospheric pressure was 
measured with a YSI electronic sensor with analog output located in the 
laboratory building at 9 m above NGVD. Data were recorded on the FRF com- 
puter. Data from this gage were compared with those from an NWS aneroid 
barometer to ensure proper operation. 
15. Microbarograph. A Weathertronics, Incorporated (Sacramento, CA) 
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 
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. 
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. 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. 
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