A Proposed Model for the International Geomagnetic Reference Field-1965

摘要: A best current model of the main geomagnetic field is presented as a response to need for an “International Geomagnetic Reference Field”. This described by series 120 spherical harmonic coefficients and their first second time derivatives from epoch 1960.0. It was derived sample all magnetic survey data available interval 1900-1964 plus recent global distribution preliminary total observations OGO-2 (1965-81A) spacecraft 1965.8. duplicate selection made resulting compared with help evaluate minimum error. noted that root —mean—square difference between two models about 30γ in force components, 0.04 degrees dip 0.3 declination at earth's surface 1965.0.