Estimation of the Length of Day (LOD) from DORIS observations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025615%3A_____%2F18%3AN0000048" target="_blank" >RIV/00025615:_____/18:N0000048 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0273117718303703?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0273117718303703?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.asr.2018.04.038" target="_blank" >10.1016/j.asr.2018.04.038</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Estimation of the Length of Day (LOD) from DORIS observations

Popis výsledku v původním jazyce

The paper is devoted to the estimation of the Length of the Day (LOD) from DORIS observations and summarizes the first successful experiment with LOD estimation at the level of geodetic precision. This result is confirmed by 9 years of DORIS data (2006.0 – 2015.0). The mean difference of the non smoothed LOD series with respect to the IERS C04 model reaches a value of tens μs and a standard deviation around 120 μs for the last years of the campaign 2012.0-2015.0. However, the mean difference with respect to the reference model varies over time, reaching negative values from -60 to -20 μs for the years 2006-2011 and positive values from 80 to 120 μs for the years 2012-2014. The time variable mean difference with respect to the changes in DORIS satellite constellation is discussed, as well as the possibility of the bias reduction applying the long-term averages of the cross-track harmonics or adjustment of the geopotential coefficient C20. Moreover, the possibility of LOD adjustment in the standard DORIS solution is discussed with focus on the station coordinates estimation. In addition, the power spectrum of the difference between estimated LOD and the reference model was performed, showing the domination of the annual signal. Also LOD estimated from single-satellite DORIS solutions was analyzed to identify satellite-specific issues. The paper includes a correlation analysis of the orbit parameters, Earth rotation parameters and the geopotential coefficient C20, based on covariance matrices from weekly solutions. High correlation around 0.96 was found for LOD and the sine amplitude of the cross-track harmonic empirical acceleration, which was also confirmed analytically.

Název v anglickém jazyce

Estimation of the Length of Day (LOD) from DORIS observations

Popis výsledku anglicky

The paper is devoted to the estimation of the Length of the Day (LOD) from DORIS observations and summarizes the first successful experiment with LOD estimation at the level of geodetic precision. This result is confirmed by 9 years of DORIS data (2006.0 – 2015.0). The mean difference of the non smoothed LOD series with respect to the IERS C04 model reaches a value of tens μs and a standard deviation around 120 μs for the last years of the campaign 2012.0-2015.0. However, the mean difference with respect to the reference model varies over time, reaching negative values from -60 to -20 μs for the years 2006-2011 and positive values from 80 to 120 μs for the years 2012-2014. The time variable mean difference with respect to the changes in DORIS satellite constellation is discussed, as well as the possibility of the bias reduction applying the long-term averages of the cross-track harmonics or adjustment of the geopotential coefficient C20. Moreover, the possibility of LOD adjustment in the standard DORIS solution is discussed with focus on the station coordinates estimation. In addition, the power spectrum of the difference between estimated LOD and the reference model was performed, showing the domination of the annual signal. Also LOD estimated from single-satellite DORIS solutions was analyzed to identify satellite-specific issues. The paper includes a correlation analysis of the orbit parameters, Earth rotation parameters and the geopotential coefficient C20, based on covariance matrices from weekly solutions. High correlation around 0.96 was found for LOD and the sine amplitude of the cross-track harmonic empirical acceleration, which was also confirmed analytically.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10508 - Physical geography

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

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

Advances in Space Research

ISSN

0273-1177

e-ISSN

—

Svazek periodika

62

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

13

Strana od-do

370-382

Kód UT WoS článku

000436913000011

EID výsledku v databázi Scopus

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