Correlation based snapshot models of the archeomagnetic field
- For the time stationary global geomagnetic field, a new modelling concept is presented. A Bayesian non-parametric approach provides realistic location dependent uncertainty estimates. Modelling related variabilities are dealt with systematically by making little subjective apriori assumptions. Rather than parametrizing the model by Gauss coefficients, a functional analytic approach is applied. The geomagnetic potential is assumed a Gaussian process to describe a distribution over functions. Apriori correlations are given by an explicit kernel function with non-informative dipole contribution. A refined modelling strategy is proposed that accommodates non-linearities of archeomagnetic observables: First, a rough field estimate is obtained considering only sites that provide full field vector records. Subsequently, this estimate supports the linearization that incorporates the remaining incomplete records. The comparison of results for the archeomagnetic field over the past 1000 yr is in general agreement with previous models whileFor the time stationary global geomagnetic field, a new modelling concept is presented. A Bayesian non-parametric approach provides realistic location dependent uncertainty estimates. Modelling related variabilities are dealt with systematically by making little subjective apriori assumptions. Rather than parametrizing the model by Gauss coefficients, a functional analytic approach is applied. The geomagnetic potential is assumed a Gaussian process to describe a distribution over functions. Apriori correlations are given by an explicit kernel function with non-informative dipole contribution. A refined modelling strategy is proposed that accommodates non-linearities of archeomagnetic observables: First, a rough field estimate is obtained considering only sites that provide full field vector records. Subsequently, this estimate supports the linearization that incorporates the remaining incomplete records. The comparison of results for the archeomagnetic field over the past 1000 yr is in general agreement with previous models while improved model uncertainty estimates are provided.…
| Author details: | Stefan MauerbergerORCiDGND, Maximilian Arthus SchannerORCiDGND, Monika KorteORCiDGND, Matthias HolschneiderORCiDGND |
|---|---|
| DOI: | https://doi.org/10.1093/gji/ggaa336 |
| ISSN: | 0956-540X |
| ISSN: | 1365-246X |
| Title of parent work (English): | Geophysical journal international |
| Publisher: | Oxford Univ. Press |
| Place of publishing: | Oxford |
| Publication type: | Article |
| Language: | English |
| Date of first publication: | 2020/07/13 |
| Publication year: | 2020 |
| Release date: | 2023/10/02 |
| Tag: | archaeomagnetism; geopotential theory; inverse theory; magnetic field variations through; palaeomagnetism; statistical methods; time |
| Volume: | 223 |
| Issue: | 1 |
| Number of pages: | 18 |
| First page: | 648 |
| Last Page: | 665 |
| Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Mathematik |
| DDC classification: | 5 Naturwissenschaften und Mathematik / 51 Mathematik / 510 Mathematik |
| Peer review: | Referiert |
