Estimation of surface density changes using a mascon method in GRACE-like missions

Abedini, Abbas; Keller, Wolfgang; Amiri-Simkooei, A. R.

doi:10.1007/s12040-020-01535-5

Cited by 3 publications

(17 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, we first show that, in case of equiangular grids, the size of the mascon should be accounted for in the applied regularization by introducing area-affected weights for the unknown parameters. This is motivated by our previous study [Abedini et al, 2021], where we showed that the patch area is directly related to the variance of the estimated surface densities: the smaller the area is, the higher the estimated variance will be. Therefore, in the estimation procedure, we suggest introducing weights for the patches proportional to their area/size.…”

Section: Introductionmentioning

confidence: 92%

“…This section consists of four subsections. The first two subsections briefly review the mascon method proposed by Abedini et al [2021]. The last two sections describe further development on the regularization of the mascon solution along with its precision description.…”

Section: Theoretical Background and Further Developmentmentioning

confidence: 99%

“…The first group uses spherical harmonics (SH) to present the mascon solutions [Bettadpur, 2007;Wahr et al, 1998], and the second group of methodologies uses the Stokes coefficients to estimate the mass concentration from the satellite-to-satellite-tracking (SST) data [Luthcke et al, 2013;Save et al, 2016;Watkins et al, 2015]. A comprehensive review of different methods and their pros and cons have been provided by Save et al [2016], Scanlon et al [2016], Jing et al [2019] and Abedini et al [2021].…”

Section: Introductionmentioning

confidence: 99%

“…In our previous study [Abedini et al, 2021], we suggested a mascon approach that uses the piecewise constant surface density functions, as local basis functions, to estimate the surface density. While other traditional mascon methods (e.g., in Luthcke et al [2013], Rowlands et al [2010], Save et al [2016] and Watkins et al [2015] have applied global basis functions, our main motivation was to avoid the series truncation that is usually applied in these mascon methods.…”

Section: Introductionmentioning

confidence: 99%

“…The truncations of high frequency terms result in aliasing and leakage errors affecting the signals of interest at lower frequencies. The advantage of our proposed mascon method is that it avoids the truncation and henceforth aim at improving the leakage problem at the cost of extensive computation time [Abedini et al, 2021].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

On the performance of equiangular mascon solution in GRACE-like missions

Abedini

Keller

Amiri-Simkooei

2021

Annals of Geophysics

Self Cite

View full text Add to dashboard Cite

Mass concentration (mascon) solutions for GRACE (Gravity Recovery and Climate Experiment) data are widely used in various regional-to-global mass change studies. The current advances in the mascon solution have mainly concentrated on improving the spatial resolution of the solution, enhancing the applied least-squares regularization, and the characterization of the solution errors. Most of the mascon solutions are obtained on the equal-area grid, inducing complexities in creating the grid and its presentation. In this regard, estimation of the mascon solutions on equiangular grids can be appealing. Furthermore, in the equal-area methods, there is no global criterion to determine the size of the mascon areas. The mascon size is usually chosen in a subjective manner which hampers the objective application of different mascon solutions. In view of these challenges, two main questions are addressed in this study: i) what kind of modifications should be made in computation scheme of the mascon solution if equiangular grids are used to account for different areas of the grid patches, and ii) in case of non-equiangular solutions, how to define an objective criterion for the patch sizes based on the resolution of both the observation and the signal of interest. We investigate the performance of the high-resolution mascon-based approach, proposed by Abedini et al. [2021], which uses GRACE-like observations similar to level-1 data for a period of one month over the Greenland region. Two main practical issues are studied on the estimation of the surface density changes as follows. First, we show that for equiangular grids, the area of the patches should be accounted for in the regularization by introducing area-affected weights for the unknown parameters. We investigate the effect of three different area-affected weighting strategies on the derived solution. Secondly in order to obtain proper size for the patches, a novel approach is presented to investigate the performance of the mascon solution using the analysis of the resolution matrix entries. The proposed resolution analysis is used to obtain the optimal patch size for the discretization of the area of interest. Based on the results, it is demonstrated that the minimum legible patch size in the Greenland area for the current settings of the GRACE observations is 0.5 degree in the NS direction and a latitude-adaptive grid-size rather than equiangular grids at high latitude regions in the EW direction.

show abstract

Section: Introductionmentioning

confidence: 92%

Section: Theoretical Background and Further Developmentmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

On the performance of equiangular mascon solution in GRACE-like missions

Abedini

Keller

Amiri-Simkooei

2021

Annals of Geophysics

Self Cite

View full text Add to dashboard Cite

show abstract

A review of different mascon approaches for regional gravity field modelling since 1968

Antoni

2022

Hist. Geo Space. Sci.

View full text Add to dashboard Cite

Abstract. The geodetic and geophysical literature shows an abundance of mascon approaches for modelling the gravity field of the Moon or Earth on global or regional scales. This article illustrates the differences and similarities between the methods, which are labelled as mascon approaches by their authors. Point mass mascons and planar disc mascons were developed for modelling the lunar gravity field from Doppler tracking data. These early models had to consider restrictions in observation geometry, computational resources or geographical pre-knowledge, which influenced the implementation. Mascon approaches were later adapted and applied for the analysis of GRACE observations of the Earth's gravity field, with the most recent methods based on the simple layer potential. Differences among the methods relate to the geometry of the mascon patches and to the implementation of the gradient and potential for field analysis and synthesis. Most mascon approaches provide a direct link between observation and mascon parameters – usually the surface density or the mass of an element – while some methods serve as a post-processing tool of spherical harmonic solutions. This article provides a historical overview of the different mascon approaches and sketches their properties from a theoretical perspective.

show abstract

A Review of Different Mascon Approaches for Regional Gravity Field Modelling since 1968

Antoni

2022

Preprint

View full text Add to dashboard Cite

Abstract. The geodetic and geophysical literature shows an abundance of mascon approaches for modelling the gravity field of Moon or Earth on global or regional scale. This article illustrates the differences and similarities of the methods, which are labelled as mascon approaches by their authors. Point mass mascons and planar disc mascons were developed for modelling the Lunar gravity field from Doppler tracking data. These early models had to consider restrictions in observation geometry, computational resources or geographical pre-knowledge, which influenced the implementation. Mascon approaches were later adapted and applied for the analysis of GRACE-observations of the Earth’s gravity field with the most recent methods based on the simple layer potential. Differences among the methods relate to the geometry of the mascon patches and in the implementation of the gradient and potential for the field analysis and synthesis. Most mascon approaches provide a direct link between observation and mascon parameter –usually the surface density or the mass of an element–, while some methods serve as a post processing tool of spherical harmonic solutions. This article provides an historical overview of the different mascon approaches and sketches their properties from theoretical perspective.

show abstract

Estimation of surface density changes using a mascon method in GRACE-like missions

Cited by 3 publications

References 22 publications

On the performance of equiangular mascon solution in GRACE-like missions

On the performance of equiangular mascon solution in GRACE-like missions

A review of different mascon approaches for regional gravity field modelling since 1968

A Review of Different Mascon Approaches for Regional Gravity Field Modelling since 1968

Contact Info

Product

Resources

About