On the modelling of M-2 tidal magnetic signatures: effects of physical approximations and numerical resolution

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F18%3A10390329" target="_blank" >RIV/00216208:11320/18:10390329 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1186/s40623-018-0967-5" target="_blank" >https://doi.org/10.1186/s40623-018-0967-5</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1186/s40623-018-0967-5" target="_blank" >10.1186/s40623-018-0967-5</a>

Jazyk výsledku

angličtina

Název v původním jazyce

On the modelling of M-2 tidal magnetic signatures: effects of physical approximations and numerical resolution

Popis výsledku v původním jazyce

The magnetic signatures of ocean M 2 tides have been successfully detected by the low-orbit satellite missions CHAMP and Swarm. They have been also used to constrain the electrical conductivity in the uppermost regions of the Earth&apos;s mantle. Here, we concentrate on the problem of accurate numerical modelling of tidally induced magnetic field, using two different three-dimensional approaches: the contraction integral equation method and the spherical har - monic-finite element method. In particular, we discuss the effects of numerical resolution, self-induction, the galvanic and inductive coupling between the oceans and the underlying mantle. We also study the applicability of a simplified two-dimensional approximation, where the ocean is approximated by a single layer with vertically averaged conduc- tivity and tidal forcing. We demonstrate that the two-dimensional approach is sufficient to predict the large-scale tidal signals observable on the satellite altitude. However, for accurate predictions of M 2 tidal signals in the areas with significant variations of bathymetry, and close to the coastlines, full three-dimensional calculations are required. The ocean-mantle electromagnetic coupling has to be treated in the full complexity, including the toroidal magnetic field generated by the vertical currents flowing from and into the mantle.

Název v anglickém jazyce

On the modelling of M-2 tidal magnetic signatures: effects of physical approximations and numerical resolution

Popis výsledku anglicky

The magnetic signatures of ocean M 2 tides have been successfully detected by the low-orbit satellite missions CHAMP and Swarm. They have been also used to constrain the electrical conductivity in the uppermost regions of the Earth&apos;s mantle. Here, we concentrate on the problem of accurate numerical modelling of tidally induced magnetic field, using two different three-dimensional approaches: the contraction integral equation method and the spherical har - monic-finite element method. In particular, we discuss the effects of numerical resolution, self-induction, the galvanic and inductive coupling between the oceans and the underlying mantle. We also study the applicability of a simplified two-dimensional approximation, where the ocean is approximated by a single layer with vertically averaged conduc- tivity and tidal forcing. We demonstrate that the two-dimensional approach is sufficient to predict the large-scale tidal signals observable on the satellite altitude. However, for accurate predictions of M 2 tidal signals in the areas with significant variations of bathymetry, and close to the coastlines, full three-dimensional calculations are required. The ocean-mantle electromagnetic coupling has to be treated in the full complexity, including the toroidal magnetic field generated by the vertical currents flowing from and into the mantle.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10500 - Earth and related environmental sciences

Projekt

<a href="/cs/project/GA17-03689S" target="_blank" >GA17-03689S: Oceánské proudění a jeho magnetická stopa v globálním a regionálním měřítku</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

EARTH PLANETS AND SPACE

ISSN

1880-5981

e-ISSN

—

Svazek periodika

70

Číslo periodika v rámci svazku

December

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

15

Strana od-do

1-15

Kód UT WoS článku

000452855100002

EID výsledku v databázi Scopus

2-s2.0-85058846407