Specifications

Section 1. Preparation and Siting
Magnetic declination is bold in this example to show its location in the table.
A positive declination is east, while a negative declination is west. The
declination in this example is 13.80 degrees. As shown in Figure 1.5-1, the
declination for Logan, UT is east, so True North for this site is 360 – 13.80, or
346.2 degrees.
FIGURE 1.5-2. Declination Angles East of True North Are
Subtracted From 0 to Get True North
FIGURE 1.5-3. Declination Angles West of True North Are
Added to 0 to Get True North
References
1
EPA, (1987). On-Site Meteorological Program Guidance for Regulatory
Modeling Applications, EPA-450/4-87-013. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina 27711.
2
WMO, (1983). Guide to Meteorological Instruments and Methods of
Observation. World Meteorological Organization No. 8, 5th edition, Geneva,
Switzerland.
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