An Alternative Method of Computing Altitude Adjustment Corrected Geomagnetic Coordinates as Applied to IGRF Epoch 2005

An updated set of altitude adjusted corrected geomagnetic coordinates has been calculated. The coordinates are based on the 10th generation IGRF model coefficients for Epoch 2005. The corrected geomagnetic coordinates at ground level are available as a lookup table, and a corresponding set of spherical harmonic coefficients for use in computing altitude adjusted corrected geomagnetic coordinates at various altitudes (after Baker and Wing [1998]) are also available. Both products are geared towards replacing the tables and coefficients used in Hein and Bhavnani [1996]. An alternative algorithm is introduced that assists in solving discontinuity problems found near the South Atlantic Anomaly and the dip equator when calculating geomagnetic coordinates from a geographic coordinate basis. The original document contains color images. All DTIC reproductions will be in black and white.