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Declination Date Latitude Longitude Elevation Model Used Declination Uncertainty 2025-09-16 24.4359° S 53.4552° W 0.0 km GPS WMM-2025 18.41° W changing by 0.13° W per year 0.40° The compass shows the bearing of the local magnetic field relative to geographic north. Magnetic declination is the angle between true north and the horizontal trace of the local magnetic field. In general, the present day field models such as the IGRF, WMMHR, and World Magnetic Model (WMM) are accurate to within 30 minutes of arc for the declination. However, local anomalies exceeding 10 degrees, although rare, do exist. Document created: 2025-09-30 00:51 UTC Help: Questions: How to interpret results geomag.models@noaa.gov Warning: The height validity of the geomagnetic components is dependent on the geomagnetic activity level. For more information see (https://www.ncei.noaa.gov/products/world-magnetic-model/accuracy-limitations-error-model) https://www.ngdc.noaa.gov/geomag/calculators/help/declinationHelp.html#interpretingresults mailto:geomag.models@noaa.gov https://www.ncei.noaa.gov/products/world-magnetic-model/accuracy-limitations-error-model