1994•Journal of geomagnetism and geoelectricityOpen access

Spherical Cap Harmonic Analysis of the Geomagnetic Field over East Asia.

Zhenchang An, Dong-hai Tan, Yuanfang Xu, V. P. Golovkov, N. M. Rotanova, T. N. Bondar

Abstract

Based on the geomagnetic data from repeat stations and observatories, the spherical cap harmonic model of the geomagnetic field over East Asia was derived. The pole of the spherical cap is at 45°N and 105°E and the half-angle of the spherical cap is 45°. The maximum index of the spherical cap harmonic analysis is 12, giving the minimum wavelength of 1635 km. The root mean square deviation values of the spherical cap harmonic model are 122.8 (north component), 103.4 (east component) and 128.0 nT (vertical component). The geomagnetic charts of East Asia were drawn at epoch 1980.0 from the spherical cap harmonic model. Furthermore, the deviation of the spherical cap harmonic model from DGRF 1980 was calculated, and the corresponding contour charts were drawn.

Open-access reader

About this research paper

What this paper is about

Why it matters

OpenAlex reports 2 citations for this work. Citation counts describe recorded attention and do not establish research quality.

Key contribution

A contribution statement is not available in the OpenAlex record.

Method / approach

Method details are not available in the OpenAlex metadata.

Main findings

Findings are not separately available in the OpenAlex metadata.

Limitations

Limitations are not available in the OpenAlex metadata.

Applications

Application details are not available in the OpenAlex metadata.

Available abstract

Key concepts: Spherical cap, Spherical harmonics, Earth's magnetic field, Zonal spherical harmonics, Geodesy, Spherical model, Harmonic, Spherical shell