Is it possible to calculate the load deformation of terrestrial water using this package? How do I get started?

[q1165600785]

Since the noise of high-order spherical harmonic coefficients will cause greater impact, the spherical harmonic coefficients truncated to the 60th order are used to calculate the load deformation of land water. The calculation formula is as follows: ∑6 ∑n Def. = R h′ n 1 + k′ n 0 n = 1 wn Pnm (cosθ) [ΔCnm cos (mλ) + ΔSnm sin (mλ)] m = 0 (1) Where: R is the radius of the earth, h′ n and k′ n are the nth order load Love numbers, Pnm (cosθ) is the associated Legendre series, θ is the colatitude, λ is the longitude, ΔCnm and ΔSnm are the differences between the processed spherical harmonic coefficients of the lunar gravity field and the spherical harmonic coefficients of the mean gravity field, and wn is the nth order isotropic Gaussian smoothing factor.

[q1165600785]

The data from the three institutions have been subjected to the removal of signals such as seabed pressure [17]. In order to obtain more accurate terrestrial water storage and surface load deformation caused by atmospheric and non-tidal ocean changes, the data are averaged to obtain better quality observation data [18]. The specific operations of data processing include correcting the first-order terms of spherical harmonic coefficients [19], replacing the C20 term [20], performing ChenP4M6 [21] and 300 km [22] Gaussian smoothing, and correcting the Glacial Isostatic Adjustment (GIA) [23]. The amplitude of the data will be weakened during the GRACE data processing. In order to restore the original amplitude of the data, the GRACE RL06 mass concentration (Masscon) data released by CSR after various corrections are used, and the scale factor method [24] is used to restore the reduction of the GRACE data amplitude caused by leakage. The scale factor calculated in this paper is 1.26, and the scale factor is used to restore the GRACE load deformation data.

[q1165600785]

Hello, this is an excerpt from a paper. I'm a beginner and don't know if it can be implemented.

[tsutterley]

hey @q1165600785,
Yes, I think it should be possible to estimate the elastic crustal uplift and apply the appropriate signal processing options with this (and associated) software. I have crustal uplift as one of the built-in unit options (mmCU) in gravity-toolkit:

More in the weeds.. Scaling GRACE/GRACE-FO data to restore amplitudes requires building what are known as "synthetics" (so that you can know "what is real" and how it is affected by the signal processing). I have separate bits of software (in model-harmonics) for processing model outputs (such as from terrestrial water storage) and trying to estimate the signal leakage (and appropriate scaling). The scaling factor calculations are based on my readings of Landerer and Swenson, 2012 and Hsu and Velicogna, 2017.

So it should be possible to put the pieces together. However, some care must be taken to make sure that your final estimates are reliable.

[q1165600785]

Teacher, which example should I refer to when starting? Can I refer to a complete example? Is there a complete example for me to refer to?

[tsutterley]

I don't have one sorry. I think I have the individual pieces that could be put together for creating and using scaling factors, but I don't have a complete example.

[q1165600785]

@tsutterley Hello, researcher I am using the script podaac_cumulus.py to download grace files

I would like to use the GLDAS Noah soil water data and the GRACE land water data to study the impact of soil water load on the CORS station's geodetic height. Is my research meaningful? Can I use model-harmonics to complete my research?

[tsutterley]

Oh cool. Yes, I think those tools might be able to help you get there.