Quick Answer
To find your local magnetic declination, use a declination chart, a compass with a rotating bezel, or a smartphone app that provides magnetic declination values. A topographic map can also help. These tools are essential for accurate navigation.
Finding Declination with a Compass
To use a compass with a rotating bezel to find your local magnetic declination, start by setting the compass to magnetic north. Then, rotate the bezel until the direction-of-travel arrow points towards your destination. The difference between magnetic north and true north is your declination.
Declination Charts and Maps
Declination charts and topographic maps provide a quick and easy way to determine local magnetic declination. These charts show declination values for specific locations, and topographic maps often include declination values as an inset or on the margin. For example, the US Geological Survey (USGS) provides declination charts for the United States. By comparing the declination value on the chart to your current location, you can determine the local declination.
Smartphone Apps and Online Resources
Several smartphone apps and online resources provide magnetic declination values for specific locations. For example, the USGS Magnetic Declination app provides declination values for the United States, and the app “Magnetic Declination” provides values for locations worldwide. These resources can be especially useful when traveling or navigating in unfamiliar areas. To use these resources, enter your location or zip code to retrieve the local declination value.
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