True North & Magnetic Declination - A Trick to Make It Stick
True North & Magnetic Declination - A Trick to Make It Stick
Navigating one's way through the great outdoors can be an exhilarating experience, but it can also be quite daunting. Whether you are an experienced explorer or a novice hiker, understanding true north and magnetic declination is essential for safe and accurate navigation. In this article, we will explore a handy trick to help you remember and apply these concepts effectively.
Let's begin by understanding the difference between true north and magnetic north. True north refers to the North Pole, the northernmost point on Earth, and it is marked by the geographic pole. On the other hand, magnetic north refers to the point where the Earth's magnetic field points vertically downwards. This point is not fixed and tends to shift over time due to the Earth's ever-changing magnetic field.
The discrepancy between true north and magnetic north is known as magnetic declination. It is the angle between the direction of True North and Magnetic North at any specific location. Magnetic declination is important to consider when using a compass for navigation. Failure to account for declination can result in significant errors while trying to follow a compass bearing to a desired destination.
So, how can we remember and apply this important concept effectively? The trick lies in understanding the acronym "EAST" - which stands for "add east, subtract west." This simple mnemonic will help you remember whether to add or subtract the magnetic declination from your compass bearing to obtain a correct true bearing.
Let's break down the trick step by step:
1. Determine your location's magnetic declination: Consult a declination map or use a compass with an adjustable declination scale to find the magnetic declination for your specific area. The map will indicate the declination as either East or West and the corresponding angle.
2. If the magnetic declination is EAST: Add the declination to your compass bearing. For example, if you need to follow a bearing of 120 degrees on your compass, and the magnetic declination is 10 degrees East, you would add 10 degrees to your reading. Therefore, your true bearing would be 130 degrees.
3. If the magnetic declination is WEST: Subtract the declination from your compass bearing. Using the same example as above, if your compass bearing is 120 degrees and the declination is 10 degrees West, you would subtract 10 degrees from your reading. Thus, your true bearing would be 110 degrees.
By remembering the "EAST" acronym, you will always know whether to add or subtract the magnetic declination correctly.
It is important to note that magnetic declination varies from location to location and changes over time. Therefore, it is crucial to stay updated on changes to magnetic declination in the area you plan to explore. Online resources, local land management offices, or experienced hikers can provide the most recent data for accurate navigation.
In conclusion, understanding true north and magnetic declination is essential for safe and accurate outdoor navigation. By utilizing the mnemonic "EAST" to add or subtract magnetic declination, you can ensure that your compass readings lead you in the right direction. So, the next time you embark on an outdoor adventure, keep the trick in mind to make true north and magnetic declination stick with you.