Water Storage Changes in Three Gorges Water Systems Area Inferred from Grace Time-Variable Gravity Data

2007 ◽  
Vol 50 (3) ◽  
pp. 650-657 ◽  
Author(s):  
Han-Sheng WANG ◽  
Zhi-Yong WANG ◽  
Xu-Dong YUAN ◽  
Patrick Wu ◽  
Elena Rangelova
Keyword(s):  
Gravity Data ◽  
Water Storage ◽  
Water Systems ◽  
Time Variable ◽  
Three Gorges ◽  
Time Variable Gravity ◽  
Variable Gravity

scholarly journals Supporting large-scale hydrogeological monitoring and modelling by time-variable gravity data

2006 ◽  
Vol 15 (1) ◽  
pp. 167-170 ◽  
Author(s):  
Andreas Güntner ◽  
Roland Schmidt ◽  
Petra Döll
Keyword(s):  
Large Scale ◽  
Gravity Data ◽  
Time Variable ◽  
Time Variable Gravity ◽  
Variable Gravity

scholarly journals An Iterative ICA-Based Reconstruction Method to Produce Consistent Time-Variable Total Water Storage Fields Using GRACE and Swarm Satellite Data

2020 ◽  
Vol 12 (10) ◽  
pp. 1639 ◽  
Author(s):  
Ehsan Forootan ◽  
Maike Schumacher ◽  
Nooshin Mehrnegar ◽  
Aleš Bezděk ◽  
Matthieu J. Talpe ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Water Storage ◽  
Time Variable ◽  
Reconstruction Technique ◽  
Reconstruction Method ◽  
Satellite Mission ◽  
Time Variable Gravity ◽  
Gravity Fields ◽  
Terrestrial Water ◽  
Variable Gravity

Observing global terrestrial water storage changes (TWSCs) from (inter-)seasonal to (multi-)decade time-scales is very important to understand the Earth as a system under natural and anthropogenic climate change. The primary goal of the Gravity Recovery And Climate Experiment (GRACE) satellite mission (2002–2017) and its follow-on mission (GRACE-FO, 2018–onward) is to provide time-variable gravity fields, which can be converted to TWSCs with ∼ 300 km spatial resolution; however, the one year data gap between GRACE and GRACE-FO represents a critical discontinuity, which cannot be replaced by alternative data or model with the same quality. To fill this gap, we applied time-variable gravity fields (2013–onward) from the Swarm Earth explorer mission with low spatial resolution of ∼ 1500 km. A novel iterative reconstruction approach was formulated based on the independent component analysis (ICA) that combines the GRACE and Swarm fields. The reconstructed TWSC fields of 2003–2018 were compared with a commonly applied reconstruction technique and GRACE-FO TWSC fields, whose results indicate a considerable noise reduction and long-term consistency improvement of the iterative ICA reconstruction technique. They were applied to evaluate trends and seasonal mass changes (of 2003–2018) within the world’s 33 largest river basins.

scholarly journals Regional acceleration in ice mass loss from Greenland and Antarctica using GRACE time-variable gravity data

2014 ◽  
Vol 41 (22) ◽  
pp. 8130-8137 ◽  
Author(s):  
I. Velicogna ◽  
T. C. Sutterley ◽  
M. R. van den Broeke
Keyword(s):  
Mass Loss ◽  
Gravity Data ◽  
Time Variable ◽  
Time Variable Gravity ◽  
Variable Gravity

scholarly journals Attenuation effect on seasonal basin-scale water storage changes from GRACE time-variable gravity

2006 ◽  
Vol 81 (4) ◽  
pp. 237-245 ◽  
Author(s):  
J. L. Chen ◽  
C. R. Wilson ◽  
J. S. Famiglietti ◽  
Matt Rodell
Keyword(s):  
Water Storage ◽  
Time Variable ◽  
Attenuation Effect ◽  
Time Variable Gravity ◽  
Basin Scale ◽  
Variable Gravity

Spherical and ellipsoidal surface mass change from GRACE time-variable gravity data

2020 ◽  
Author(s):  
Michal Šprlák ◽  
Khosro Ghobadi-Far ◽  
Shin-Chan Han ◽  
Pavel Novák
Keyword(s):  
Gravity Field ◽  
Gravitational Potential ◽  
Gravity Data ◽  
Time Variable ◽  
Mass Change ◽  
Spherical Approximation ◽  
Surface Mass ◽  
Time Variable Gravity ◽  
The Earth ◽  
Variable Gravity

<p>The problem of estimating mass redistribution from temporal variations of the Earth’s gravity field, such as those observed by GRACE, is non-unique. By approximating the Earth’s surface by a sphere, surface mass change can be uniquely determined from time-variable gravity data. Conventionally, the spherical approach of Wahr et al. (1998) is employed for computing the surface mass change caused, for example, by terrestrial water and glaciers. The accuracy of the GRACE Level 2 time-variable gravity data has improved due to updated background geophysical models or enhanced data processing. Moreover, time series analysis of ∼15 years of GRACE observations allows for determining inter-annual and seasonal changes with a significantly higher accuracy than individual monthly fields. Thus, the improved time-variable gravity data might not tolerate the spherical approximation introduced by Wahr et al. (1998).</p><p>A spheroid (an ellipsoid of revolution) represents a closer approximation of the Earth than a sphere, particularly in polar regions. Motivated by this fact, we develop a rigorous method for determining surface mass change on a spheroid. Our mathematical treatment is fully ellipsoidal as we concisely use Jacobi ellipsoidal coordinates and exploit the corresponding series expansions of the gravitational potential and of the surface mass. We provide a unique one-to-one relationship between the ellipsoidal spectrum of the surface mass and the ellipsoidal spectrum of the gravitational potential. This ellipsoidal spectral formula is more general and embeds the spherical approach by Wahr et al. (1998) as a special case. We also quantify the differences between the spherical and ellipsoidal approximations numerically by calculating the surface mass change rate in Antarctica and Greenland.</p><p> </p><p>References:</p><p>Wahr J, Molenaar M, Bryan F (1998) Time variability of the Earth’s gravity field: Hydrological and oceanic effects and their possible detection using GRACE. Journal of Geophysical Research: Solid Earth, 103(B12), 30205-30229.</p>

Sign in / Sign up

Export Citation Format

Share Document