How to adjust the Brunton transit (compass) for magnetic declination.

This video covers online access to NOAA's magnetic declination calculator, how to use the calculator to determine magnetic declination for a field area, the seemingly backwards positions of "E" and "W" on the Brunton and the counterclockwise graduation of azimuth (0-360), as they relate to the adjustment for declination, a rationale for the declination adjustment, and how to make the adjustment.

Note that I misspoke at one point in the discussion of the magnetic declination calculator. Ater 1 year (January 4, 2022, not 2021), the magnetic declination on Signal Mountain, TN, would be 4° 53' W, considering that it's changing at a rate of 4' W per year. On January 4, 2021, when the video was made, the declination was 4° 49' W.

At the time that this video was posted, mid December 2024, NOAA's magnetic declination calculator was accessed at

[ Ссылка ]

This video was produced during the spring of 2021, at the heart of COVID, as part of my effort to teach a field methods class, partially online.

CHAPTERS (PARTS)
00:00 Intro
00:40 NOAA's mag. declination calculator
03:56 "E", "W", 0-360, backwards?
05:27 Rationale for declination adjustment
06:22 Making the adjustment

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