10:00 AM - 10:15 AM
[SGD01-05] Improvement of method that makes Japanese old and dense gravity data consistent with Japan gravity standardization net 2016
Keywords:Japan Gravity Standardization Net 2016 (JGSN2016)
GNSS-derived orthometric height determination has been recently developed. As a result, the importance of land gravity data densely covering the whole country has been gradually increasing because the data has been increasingly utilized as fundamental data for modeling of geoid, a reference surface for orthometric height. The latest, Highly-reliable land gravity data covering the country are essential for improving accuracy and reliability of geoid model. However, it is almost impossible to obtain new data referring JGSN2016 with in short period by newly conducting time- and cost-consuming land gravity measurement for the whole country.
To resolve these problems, we have developed a method that makes Japanese old and dense gravity data consistent with JGSN2016. We reported a solution for that problem in JpGU2016 and JpGU2017. In the method, we estimated uplift/subsidence displacement of observation station due to crustal deformation, mass redistribution caused by earthquake event and system offset that has existed since establishment of each gravity reference individually. Consequently, we achieve to convert old gravity data to new gravity data in about 40 micro Gal precision. We will report contribution for geoid modeling and application of this method for gravity data of other institutions.