HydroGeodesy & Gravity Field @ITU
Earth Observation and Modeling
 
I T U _ G G C 1 6
 
ITU_GGC16 is a satellite-only gravity field model complete to degree and order 280 determined from the combination of ITU_GRACE16 (upto d/o 180) and GO_CONS_GCF_2_TIM_R5 (upto d/o 280) models (Akyilmaz et al., 2016, Brockmann et al., 2014). The combination was performed at the normal equation level with optimal variance component estimation.
 
GIF48 up to d/o 180 served as a priori gravity field model.
 
Though GO_CONS_GCF_2_TIM_R5 NEQs originally do not refer to any a-priori gravity field, the RHS of the NEQs were modified so that the NEQs from GOCE contribution also refers to GIF48 upto d/o 180 before the combination.
 
No rate terms were modeled, and no corrections for earthquakes have been applied. For additional details on the background modeling,see the GFZ RL05 processing standards document available at:
ftp://podaac.jpl.nasa.gov/allData/grace/docs/L2-GFZ_ProcStds_0005_v1.1.pdf
 
The solution reveals the significant contribution/improvement from GRACE upto d/o 130. Beyond that, GOCE dominates the combined solution as expected.
 
Solution can be used for independent comparison and combination on normal equation level with other terrestrial gravity data, and altimetry.
 
Please cite ITU_GGC16 as follows:
Akyilmaz, O., Ustun, A., Aydın, C., Arslan, N.,Doganalp, S., Guney, C., Mercan, H., Uygur, S.O., Uz, M., Yağcı, O (2016), High Resolution Gravity Field Determination and Monitoring of Regional Mass Variations using Low-Earth Orbit Satellites, Final Report of Project # 113Y155
 
For further info, please contact:
Dr. Orhan Akyilmaz (akyilma2@itu.edu.tr)
 
Acknowledgement:
This work is supported by TUBITAK under grant no 113Y155.

[Researchers: O. Akyilmaz, A. Ustun, C. Aydin, N. Arslan, S. Doganalp, C. Guney, H. Mercan, O. Yagci, S.O. Uygur, M. Uz]
[External Collaborators: C.K. Shum, K. Shang (OSU)] Dr. W.-D. Schuh and Dr. J.M. Brockmann are gratefully acknowledged for providing GO_CONS_GCF_2_TIM_R5 NEQs.