Regional gravity field modelling from GOCE observables

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F49777513%3A23520%2F17%3A43929217" target="_blank" >RIV/49777513:23520/17:43929217 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.asr.2016.09.024" target="_blank" >http://dx.doi.org/10.1016/j.asr.2016.09.024</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.asr.2016.09.024" target="_blank" >10.1016/j.asr.2016.09.024</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Regional gravity field modelling from GOCE observables

Popis výsledku v původním jazyce

In this article we discuss a regional recovery of gravity disturbances at the mean geocentric sphere approximating the Earth over the area of Central Europe from satellite gravitational gradients. For this purpose, we derive integral formulas which allow converting the gravity disturbances onto the disturbing gravitational gradients in local north-oriented frame (LNOF). The derived formulas are free of singularities in case of r &lt; R. We then investigate three numerical approaches for solving their inverses. In the initial approach, the integral formulas are firstly modified for solving individually the near- and distant-zone contributions. While the effect of the near-zone gravitational gradients is solved as an inverse problem, the effect of the distant-zone gravitational gradients is computed by numerical integration from a global equiangular grid synthesized from the global gravitational model (GGM) TIM-r4. In the second approach, we further elaborate the first scenario by reducing measured gravitational gradients for gravitational effects of topographic masses. In the third approach, we apply additional modification by reducing gravitational gradients for the reference GGM. In all approaches we determine the gravity disturbances from each of the four accurately measured gravitational gradients separately as well as from their combination. Our regional gravity field solutions are based on the GOCE EGG_TRF_2 gravitational gradients collected within the period from November 1 2009 until January 11 2010. Obtained results are compared with EGM2008, DIR-r1, TIM-r1 and SPW-r1. The best fit, in terms of RMS (2.9 mGal), is achieved for EGM2008 while using a third approach which combine all four well-measured gravitational gradients. This is explained by the fact that a-priori information about Earth&apos;s gravitational field up to degree and order 180 was used.

Název v anglickém jazyce

Regional gravity field modelling from GOCE observables

Popis výsledku anglicky

In this article we discuss a regional recovery of gravity disturbances at the mean geocentric sphere approximating the Earth over the area of Central Europe from satellite gravitational gradients. For this purpose, we derive integral formulas which allow converting the gravity disturbances onto the disturbing gravitational gradients in local north-oriented frame (LNOF). The derived formulas are free of singularities in case of r &lt; R. We then investigate three numerical approaches for solving their inverses. In the initial approach, the integral formulas are firstly modified for solving individually the near- and distant-zone contributions. While the effect of the near-zone gravitational gradients is solved as an inverse problem, the effect of the distant-zone gravitational gradients is computed by numerical integration from a global equiangular grid synthesized from the global gravitational model (GGM) TIM-r4. In the second approach, we further elaborate the first scenario by reducing measured gravitational gradients for gravitational effects of topographic masses. In the third approach, we apply additional modification by reducing gravitational gradients for the reference GGM. In all approaches we determine the gravity disturbances from each of the four accurately measured gravitational gradients separately as well as from their combination. Our regional gravity field solutions are based on the GOCE EGG_TRF_2 gravitational gradients collected within the period from November 1 2009 until January 11 2010. Obtained results are compared with EGM2008, DIR-r1, TIM-r1 and SPW-r1. The best fit, in terms of RMS (2.9 mGal), is achieved for EGM2008 while using a third approach which combine all four well-measured gravitational gradients. This is explained by the fact that a-priori information about Earth&apos;s gravitational field up to degree and order 180 was used.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10508 - Physical geography

Projekt

<a href="/cs/project/LO1506" target="_blank" >LO1506: Podpora udržitelnosti centra NTIS - Nové technologie pro informační společnost</a><br>

Návaznosti

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

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

ADVANCES IN SPACE RESEARCH

ISSN

0273-1177

e-ISSN

—

Svazek periodika

59

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

14

Strana od-do

114-127

Kód UT WoS článku

000392769500011

EID výsledku v databázi Scopus

2-s2.0-85006415946