earth rotation
Recently Published Documents


TOTAL DOCUMENTS

577
(FIVE YEARS 73)

H-INDEX

29
(FIVE YEARS 5)

Author(s):  
Suresh K

We are on a planet that orbits the Sun which emits a huge amount of energy. The climate we experience is a result of an energy gradient across Earth and an imbalance in energy across the world due to axial tilt of Earth rotation.


Mathematics ◽  
2021 ◽  
Vol 9 (24) ◽  
pp. 3223
Author(s):  
Mostafa M. A. Khater ◽  
Aliaa Mahfooz Alabdali

This research paper investigates the accuracy of a novel computational scheme (Khater II method) by applying this new technique to the fractional nonlinear Ostrovsky (FNO) equation. The accuracy of the obtained solutions was verified by employing the Adomian decomposition (AD) and El Kalla (EK) methods. The AD and EK methods are considered as two of the most accurate semi-analytical schemes. The FNO model is a modified version of the well-known Korteweg–de Vries (KdV) equation that considers the effects of rotational symmetry in space. However, in the KdV model, solutions to the KdV equations substitute this effect with radiating inertia gravity waves, and thus this impact is ignored. The analytical, semi-analytical, and accuracy between solutions are represented in some distinct plots. Additionally, the paper’s novelty and its contributions are demonstrated by comparing the obtained solutions with previously published results.


2021 ◽  
Vol 2103 (1) ◽  
pp. 012039
Author(s):  
D A Trofimov ◽  
S D Petrov ◽  
P V Movsesyan ◽  
K V Zheltova ◽  
V I Kiyaev

Abstract The extreme acceleration of the Earth rotation observed in the summer of 2020 is considered. It is concluded that this phenomenon is a consequence of two factors: the longterm acceleration of the Earth rotation, which has been observed since the 1970s, and the extremely strong meteorological excitation of the LOD, which took place in the summer of 2020. The coincidence of the anomaly of the AAM and the geomagnetic Dst index, as well as the correlation between the LOD on the one hand and the solar wind speed and the Gaussian coefficients of the expansion of the Earth’s magnetic field, on the other, are noted. The problem of negative leap second is considered. Preliminary estimates have been made of introduction of a negative leap second, if the current trends in the behavior of UT1-UTC continue. The conclusion is made about the low probability of such an event.


2021 ◽  
Vol 95 (9) ◽  
Author(s):  
Alexander A. Harker ◽  
Michael Schindelegger ◽  
Rui M. Ponte ◽  
David A. Salstein

AbstractWe revisit the problem of modeling the ocean’s contribution to rapid, non-tidal Earth rotation variations at periods of 2–120 days. Estimates of oceanic angular momentum (OAM, 2007–2011) are drawn from a suite of established circulation models and new numerical simulations, whose finest configuration is on a "Image missing"$$^\circ $$ ∘ grid. We show that the OAM product by the Earth System Modeling Group at GeoForschungsZentrum Potsdam has spurious short period variance in its equatorial motion terms, rendering the series a poor choice for describing oceanic signals in polar motion on time scales of less than $$\sim $$ ∼ 2 weeks. Accounting for OAM in rotation budgets from other models typically reduces the variance of atmosphere-corrected geodetic excitation by $$\sim $$ ∼ 54% for deconvolved polar motion and by $$\sim $$ ∼ 60% for length-of-day. Use of OAM from the "Image missing"$$^\circ $$ ∘ model does provide for an additional reduction in residual variance such that the combined oceanic–atmospheric effect explains as much as 84% of the polar motion excitation at periods < 120 days. Employing statistical analysis and bottom pressure changes from daily Gravity Recovery and Climate Experiment solutions, we highlight the tendency of ocean models run at a 1$$^\circ $$ ∘ grid spacing to misrepresent topographically constrained dynamics in some deep basins of the Southern Ocean, which has adverse effects on OAM estimates taken along the 90$$^\circ $$ ∘ meridian. Higher model resolution thus emerges as a sensible target for improving the oceanic component in broader efforts of Earth system modeling for geodetic purposes.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Christian Schubert ◽  
Sven Abend ◽  
Matthias Gersemann ◽  
Martina Gebbe ◽  
Dennis Schlippert ◽  
...  

AbstractThe sensitivity of light and matter-wave interferometers to rotations is based on the Sagnac effect and increases with the area enclosed by the interferometer. In the case of light, the latter can be enlarged by forming multiple fibre loops, whereas the equivalent for matter-wave interferometers remains an experimental challenge. We present a concept for a multi-loop atom interferometer with a scalable area formed by light pulses. Our method will offer sensitivities as high as $$2\times 10^{-11}$$ 2 × 10 - 11  rad/s at 1 s in combination with the respective long-term stability as required for Earth rotation monitoring.


2021 ◽  
Vol 13 (15) ◽  
pp. 3046
Author(s):  
Xingxing Li ◽  
Hongmin Zhang ◽  
Keke Zhang ◽  
Yongqiang Yuan ◽  
Wei Zhang ◽  
...  

Earth rotation parameters (ERP) are one of the key parameters in realization of the International Terrestrial Reference Frames (ITRF). At present, the International Laser Ranging Service (ILRS) generates the satellite laser ranging (SLR)-based ERP products only using SLR observations to Laser Geodynamics Satellite (LAGEOS) and Etalon satellites. Apart from these geodetic satellites, many low Earth orbit (LEO) satellites of Earth observation missions are also equipped with laser retroreflector arrays, and produce a large number of SLR observations, which are only used for orbit validation. In this study, we focus on the contribution of multiple LEO satellites to ERP estimation. The SLR and Global Positioning System (GPS) observations of the current seven LEO satellites (Swarm-A/B/C, Gravity Recovery and Climate Experiment (GRACE)-C/D, and Sentinel-3A/B) are used. Several schemes are designed to investigate the impact of LEO orbit improvement, the ERP quality of the single-LEO solutions, and the contribution of multiple LEO combinations. We find that ERP estimation using an ambiguity-fixed orbit can attain a better result than that using ambiguity-float orbit. The introduction of an ambiguity-fixed orbit contributes to an accuracy improvement of 0.5%, 1.1% and 15% for X pole, Y pole and station coordinates, respectively. In the multiple LEO satellite solutions, the quality of ERP and station coordinates can be improved gradually with the increase in the involved LEO satellites. The accuracy of X pole, Y pole and length-of-day (LOD) is improved by 57.5%, 57.6% and 43.8%, respectively, when the LEO number increases from three to seven. Moreover, the combination of multiple LEO satellites is able to weaken the orbit-related signal existing in the single-LEO solution. We also investigate the combination of LEO satellites and LAGEOS satellites in the ERP estimation. Compared to the LAGEOS solution, the combination leads to an accuracy improvement of 0.6445 ms, 0.6288 ms and 0.0276 ms for X pole, Y pole and LOD, respectively. In addition, we explore the feasibility of a one-step method, in which ERP and the orbit parameters are jointly determined, based on SLR and GPS observations, and present a detailed comparison between the one-step solution and two-step solution.


2021 ◽  
Vol 21 (7) ◽  
pp. 167
Author(s):  
Huan Zhou ◽  
De-Zhen Xu ◽  
Jian-Guo Yan ◽  
Shao-Wu Chen ◽  
Hai-Tao Li

2021 ◽  
Vol 136 (5) ◽  
Author(s):  
Andrea Basti ◽  
Nicolò Beverini ◽  
Filippo Bosi ◽  
Giorgio Carelli ◽  
Donatella Ciampini ◽  
...  

AbstractGINGERINO is one of the most sensitive Sagnac laser-gyroscopes based on an heterolithic mechanical structure. It is a prototype for GINGER, the laser gyroscopes array proposed to reconstruct the Earth rotation vector and in this way to measure General Relativity effects. Many factors affect the final sensitivity of laser gyroscopes, in particular, when they are used in long-term measurements, slow varying environmental parameters come into play. To understand the role of different terms allows to design more effective mechanical as well as optical layouts, while a proper model of the dynamics affecting long-term (low frequency) signals would increase the effectiveness of the data analysis for improving the overall sensitivity. In this contribution, we focus our concerns on the effects of room temperature and pressure aiming at further improving mechanical design and long-term stability of the apparatus. Our data are compatible with a local orientation changes of the Gran Sasso site below $$\mu $$ μ rad as predicted by geodetic models. This value is consistent with the requirements for GINGER and the installation of an high-sensitivity Sagnac gyroscope oriented at the maximum signal, i.e. along the Earth rotation axes.


2021 ◽  
Vol 11 (2) ◽  
pp. 133-137
Author(s):  
Breno Eduardo dos Santos Alves ◽  
Alexandre Santos Fernandes Filho ◽  
Hellem Cristina Teixeira Rodrigues ◽  
Marcus Vinicius Zamorim da Costa ◽  
Rayssa Soares da Silva ◽  
...  

Objetivou-se analisar o eixo de rotação da terra no período superior a um ano, considerando a ocorrência de um fenômeno natural, como o terremoto do Japão ocorrido em março de 2011, para saber se o mesmo contribuiu para alterar o eixo de rotação da Terra e quais as variações sofridas durante o período de estudo. Foram coletados os dados na página oficial do IERS (International Earth Rotation and Reference Systems Service) os dados de orientação da Terra, que são encontrados nos Boletins B, enumerados e coletados no intervalo do boletim B 278 até boletim B 285, que representam o período de setembro de 2010 a setembro de 2011. Com o uso do Excel 2016, tabelou-se e organizaram-se os dados, os quais se referem ao movimento do polo de x e y na unidade de milésimo de segundo (mas). Feito a organização, houve a criação do gráfico no próprio software. As figuras expostas demonstram que as oscilações obedeceram ao padrão cíclico do Movimento de Chandler, de modo que é possível inferir que, apesar da magnitude do evento, não houve interferência sobre o movimento analisado.


2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Rüdiger Haas ◽  
Eskil Varenius ◽  
Saho Matsumoto ◽  
Matthias Schartner

AbstractWe present first results for the determination of UT1-UTC using the VLBI Global Observing System (VGOS). During December 2019 through February 2020, a series of 1 h long observing sessions were performed using the VGOS stations at Ishioka in Japan and the Onsala twin telescopes in Sweden. These VGOS-B sessions were observed simultaneously to standard legacy S/X-band Intensive sessions. The VGOS-B data were correlated, post-correlation processed, and analysed at the Onsala Space Observatory. The derived UT1-UTC results were compared to corresponding results from standard legacy S/X-band Intensive sessions (INT1/INT2), as well as to the final values of the International Earth Rotation and Reference Frame Service (IERS), provided in IERS Bulletin B. The VGOS-B series achieves 3–4 times lower formal uncertainties for the UT1-UTC results than standard legacy S/X-band INT series. The RMS agreement w.r.t. to IERS Bulletin B is slightly better for the VGOS-B results than for the simultaneously observed legacy S/X-band INT1 results, and the VGOS-B results have a small bias only with the smallest remaining standard deviation.


Sign in / Sign up

Export Citation Format

Share Document