Widely known as an archipelago, Indonesia has a wide variety of topographical characteristics from Sabang to Merauke. Its abundance of seismic activities also puts the country into the category of Ring of Fire Zone. Indonesia's diverse geographical conditions pose both a challenge and an obligation for the Geospatial Information Agency to provide information on the matter.
B.I.G's obligations are set out under Law No. 4 of 2011 concerning geospatial information. OneMap policy also adds the role of the geospatial information in policy formulation, decision making, and implementation of geospatial related activities. It means that we hope that with the policy of OneMap policy, With this one map, as I said earlier, we can complete the high-end use of land. by launching the Indonesian Geospatial Reference System.
The Center of Geodetic Control Network and Geodynamics owes its success to the efforts of these workgroups. Horizontal Control Network and Geodynamics Workgroup In today's digital era, data is the most valuable asset. Those in possession of data, geospatial data included, will run the world. In the past 24 years, INACORS, managed by the Geospatial Information Agency, has been fulfilling its duty as the National Geospatial Reference Data Station as a part of Indonesia National Geodetic Control Network.
Alongside INACORS, the National Horizontal Control Network or JKHN is also part of our National Geospatial Reference System. Both of these data are working side by side to accurately capture coordinates on Earth's surface. INACORS networks are rapidly growing that in 2020 there are 245 INACORS stations spread all over Indonesia, covering data points in the entire country.
The National Horizontal Control Network pillars are spread all over Indonesia regions as a physical implementation of our national datum, the SRGI 2013. Data quality is our main priority. Data management and monitoring every INUCOR station component performance is part of our daily routines. It is our commitment to always use high-quality equipment and software.
To be able to produce the best data that is beneficial to the public, geospatial data management and stations maintenance are always kept under close observation. Every malfunction is immediately dealt with, so that the system can function normally again. One of INACOR's main roles is to support accelerated surveys and mapping processes in Indonesia.
Using real-time kinematic method that can go up to 50 kilometers coverage, allowing users to be able to generate real-time point coordinates in high precision up to centimeters accuracy level within seconds or minutes. The National Geodetic Control Network is maintained by doing physical checkups and by updating the coordinate values regularly. Coordinate values updating process is conducted every 5 years for JKHN pillars.
In specific regions that are prone to geodynamic phenomena, some JKHN pillars receive annual coordinate updates to gain understanding of geodynamic phenomena happening in that region. As a national reference point, INACOR's coordinates accuracy is always monitored carefully by examining the time series coordinate and its velocity vector values from daily GNSS data processing results. Noise in the GNSS data can also be extracted to produce other information, such as total electron content and precipitable water vapor.
At the moment, BIG is cooperating in a project with the German Research Center for Geosciences, aiming to create an advanced system of GNSS data utilization, particularly to further support Indonesia's Tsunami Early Warning System. Vertical Control Network and Tide Workgroup extending more than 17,000 islands, Indonesia is a perfect example of an archipelago. Indonesia's complex landscapes present many challenges in providing a national geodetic reference system. Apart from GeoID, tidal data is also used as an alternative to fulfill demands for the vertical reference system. Tidal data is also used for the purpose of ship navigation, natural disasters, and maritime studies.
The Geospatial Information Agency has 170 tight stations located throughout Indonesia. We use three types of sensors in data recording, radar, pressure, and float sensors. These three sensors act as a backup for one another. in case one of the sensors experiences failure. Tidal data recorded in the field is later validated and processed using the least square method to generate tidal datums.
The tidal data quality is continuously refined, particularly to fulfill the needs for navigational purposes and natural disasters monitoring. The current tidal data utilizes a 5-second interval streaming feature. supported by GPRS communication system.
However, in several areas with underdeveloped infrastructure, communication remains an issue. The demand for speedy and accurate data has become even more important today. Therefore, addressing communication issue is vital in data provision partnerships, particularly for data required by the Indonesia's Tsunami Early Warning System or INETUS, which involves other government agencies as BIG's partners.
As a long-term objective towards 2024, BIG will continue to build tidal stations in various locations in Indonesia. BIG will also involve academics from Bandung Institute of Technology to develop tidal model. These efforts are carried out to continuously improve data quality.
which will be useful particularly for natural disasters management, maritime studies, and the development of large-scale mapping. Reveille Control Network and GeoEd Workgroup Indonesia's GeoEd has its own unique characteristics. 17,000 islands with different tidal waters specific to each region, making it complicated to develop Indonesia's GeoEd model.
Collecting gravity data and developing Indonesia's GeoIT model became the main task of the Gravity Control Network and GeoIT workgroup which encompasses five surveys. Absolute gravity measurement, airborne, terrestrial, shipboard and GeoIT validation measurement. To develop the geowidth model, the remove-restore method is used. Here's the basic concept of the remove-restore method. Residual terrain modeling is one of the remove-restore calculation methods that was chosen for Indonesia's geowidth modeling, which takes into account short wavelength component on the Earth's surface or topographical aspects.
Once the complete data is acquired, the team moves on to the next stage. The Graphsoft modified software from DTU Denmark is used to process the data. The data input is divided into three, long wavelengths EGM, degree 360 data, residual medium wavelength data, and short wavelength data from the National Digital Elevation Model or DEMNAS, National Bathymetry or BATNAS, and SRTM. This year, BIG has successfully launched the Indonesia GeoEd Model INA GeoEd 2020 to the public.
Accuracy in the calculation process to validate geoid refers to the approximate mean difference geometric undulation on each validation point compared to the determined gravimetric undulation. Geometric undulation is derived from meticulous calculation of the difference between geodetic height from GNSS measurement with orthometric heights from leveling measurement that had been corrected using gravity data. Here's the result of the Indonesia's GEO-8 model development along with detailed accuracy of the Indonesian GEO-8.
Achieving the geoid accuracy level of 5 cm fraction for a better future with three action plans. Collecting grid airborne gravity, shipborne gravity data, and increasing geoid validation tracks. Integration with the Global Navigation Satellite System or GNSS Industrial.
Resulting in a GeoID data with tested validity and ready to use for industrial development. Precise GeoID for a better future. Since its establishment in October 1969, B.I.G. has launched several coordinate references systems.
Beginning with ID74 which was launched in 1974 and was later changed to DGN95 in 1995. As technology advances, the coordinate reference system is continuously updated, which now has become SRGI 2013. SRGI 2013 provides a variety of public service information, from geodetic control network, geoid model, deformation model, to atmospheric model. All can be accessed through the website srgi.big.go.id. For Indonesian tidal model and Aynakor services in particular, they are available on a separate website.
The information is accessible through tides.big.go.id. and nrtk.big.gov.id. Innovation is a part of BIG's work in refining the geospatial reference system.
A strong research is our means to organize a better Indonesia.