TY - GEN

T1 - LUH-GRACE2018

T2 - 27th General Assembly of the International Union of Geodesy and Geophysics, IUGG 2019

AU - Koch, Igor

AU - Flury, Jakob

AU - Naeimi, Majid

AU - Shabanloui, Akbar

N1 - Funding Information: Acknowledgements We are thankful for the valuable comments of the two anonymous reviewers who helped to improve the manuscript considerably. Part of this work was funded by Deutsche Forschungs-gemeinschaft (DFG) (SFB1128 geo-Q: Collaborative Research Centre 1128 “Relativistic Geodesy and Gravimetry with Quantum Sensors”).

PY - 2020/3/11

Y1 - 2020/3/11

N2 - In this contribution, we present the LUH-GRACE2018 time series of monthly gravity field solutions covering the period January 2003–March 2016. The solutions are obtained from GRACE K-Band Range Rate (KBRR) measurements as main observations. The monthly solutions are computed using the in-house developed GRACE-SIGMA software. The processing is based on dynamic orbit and gravity field determination using variational equations and consists of two main steps. In the first step, 3-hourly orbital arcs of the two satellites and the state transition and sensitivity matrices are dynamically integrated using a modified Gauss-Jackson integrator. In this step, initial state vectors and 3D accelerometer bias parameters are adjusted using GRACE Level-1B reduced-dynamic positions as observations. In the second step, normal equations are accumulated and the normalized spherical harmonic coefficients up to degree and order 80 are estimated along with arc-wise initial states, accelerometer biases and empirical KBRR parameters. Here KBRR measurements are used as main observations and reduced-dynamic positions are introduced to solve for the low frequency coefficients. In terms of error degree standard deviations as well as Equivalent Water Heights (EWH), our gravity field solutions agree well with RL05 solutions of CSR, GFZ and JPL.

AB - In this contribution, we present the LUH-GRACE2018 time series of monthly gravity field solutions covering the period January 2003–March 2016. The solutions are obtained from GRACE K-Band Range Rate (KBRR) measurements as main observations. The monthly solutions are computed using the in-house developed GRACE-SIGMA software. The processing is based on dynamic orbit and gravity field determination using variational equations and consists of two main steps. In the first step, 3-hourly orbital arcs of the two satellites and the state transition and sensitivity matrices are dynamically integrated using a modified Gauss-Jackson integrator. In this step, initial state vectors and 3D accelerometer bias parameters are adjusted using GRACE Level-1B reduced-dynamic positions as observations. In the second step, normal equations are accumulated and the normalized spherical harmonic coefficients up to degree and order 80 are estimated along with arc-wise initial states, accelerometer biases and empirical KBRR parameters. Here KBRR measurements are used as main observations and reduced-dynamic positions are introduced to solve for the low frequency coefficients. In terms of error degree standard deviations as well as Equivalent Water Heights (EWH), our gravity field solutions agree well with RL05 solutions of CSR, GFZ and JPL.

KW - GRACE

KW - GRACE Follow-On

KW - Gravity field recovery

KW - Time-variable gravity field

UR - http://www.scopus.com/inward/record.url?scp=85142623028&partnerID=8YFLogxK

U2 - 10.1007/1345_2020_92

DO - 10.1007/1345_2020_92

M3 - Conference contribution

AN - SCOPUS:85142623028

SN - 9783031098567

T3 - International Association of Geodesy Symposia

SP - 67

EP - 75

BT - Beyond 100: The Next Century in Geodesy

A2 - Freymueller, Jeffrey T.

A2 - Sánchez, Laura

PB - Springer Science and Business Media Deutschland GmbH

Y2 - 8 July 2019 through 18 July 2019

ER -