APPLYING THE METHOD OF MAXIMUM CONTRIBUTIONS TO THE MAGNETOGRAM INVERSION TECHNIQUE
Journal Title: Solar-Terrestrial Physics - Year 2020, Vol 6, Issue 4
Abstract
Fundamentals of the spherical harmonic analysis (SHA) of the geomagnetic field were created by Gauss. They acquired the classical Chapman — Schmidt form in the first half of the XXth century. The SHA method was actively developed for domestic geomagnetology by IZMIRAN, and then, since the start of the space age, by ISTP SB RAS, where SHA became the basis for a comprehensive method of MIT (magnetogram inversion technique). SHA solves the inverse problem of potential theory and calculates sources of geomagnetic field variations (GFV) - internal and external electric currents. The SHA algorithm forms a system of linear equations (SLE), which consists of 3K equations (three components of the geomagnetic field, K is the number of ground magnetic stations). Small changes in the left and (or) right side of such SLE can lead to a significant change in unknown variables. As a result, two consecutive instants of time with almost identical GFV are approximated by significantly different SHA coefficients. This contradicts both logic and real observations of the geomagnetic field. The inherent error of magnetometers, as well as the method for determining GFV, also entails the instability of SLE solution. To solve such SLEs optimally, the method of maximum contribution (MMC) was developed at ISTP SB RAS half a century ago. This paper presents basics of the original method and proposes a number of its modifications that increase the accuracy and (or) speed of solving the SLEs. The advantage of MMC over other popular methods is shown, especially for the Southern Hemisphere of Earth.
Authors and Affiliations
Penskikh Yu. V.
Keywords
Related Articles
- EP ID EP700244
- DOI 10.12737/stp-64202009
- Views 139
- Downloads 0
INTERACTIVE COMPUTER MODEL FOR AURORA FORECAST AND ANALYSIS
An interactive computer model of a short-term (with a horizon 30–70 min) forecast of aurora intensity has been developed in the form of a web-based geoinformation system. The OVATION-Prime empirical model is used as the...
ESTIMATED INFLUENCE OF STRATOSPHERIC ACTIVITY ON THE IONOSPHERE ACCORDING TO MEASUREMENTS WITH ISTP SB RAS TOOLS
We present the results of a comprehensive study of the manifestation of wave activity with periods of internal gravity waves (IGW) in various regions of the atmosphere: in the stratosphere, upper mesosphere, and in the F...
On possible relation of earthquakes with the sign change of the interplanetary magnetic field radial component
This work is devoted to an experimental study of the possible relationship between earthquakes and interplanetary magnetic field (IMF) variations. For the analysis, we use world and regional catalogs of earthquakes and a...
THE FIRST COMPARATIVE ANALYSIS OF METEOR ECHO AND SPORADIC SCATTERING IDENTIFIED BY A SELF-LEARNED NEURAL NETWORK IN EKB AND MAGW ISTP SB RAS RADAR DATA
The paper describes the current version (v.1.1) of the algorithm for automatic classification of signals received by ISTP SB RAS decameter coherent scatter radars. The algorithm is a self-learning neural network that det...
ASTROCLIMATIC STATISTICS AT THE SAYAN SOLAR OBSERVATORY
The paper analyzes meteorological and optical characteristics of the atmosphere at the Sayan Solar Observatory (SSO) and the future 3 m Large Solar Telescope (LST-3). We examine spatial features of changes in astroclimat...