Specifications

RAWS-F Remote Automated Weather Station for Fire Weather
FIGURE 8.3-2. A declination angle east of True North (positive) is
subtracted from 360 (0) degrees to find True North
FIGURE 8.3-3. A declination angle west of True North (negative) is
subtracted from 0 (360) degrees to find True North
8.3.2 USGS Web Calculator
The USGS provides an easy way of determining declination of a specific site.
Since magnetic declination fluctuates with time, it should be adjusted each time
the wind sensor orientation is adjusted. The calculator can be accessed at:
www.ngdc.noaa.gov/geomagmodels/Declination.jsp
. Figure 8.3-4 shows an
example for Logan, UT.
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