The National Land Survey of Finland (NLS) has announced the release of a new geoid model that represents the shape of the Earth with 30% more accuracy than previous models.
Previously, Finland’s official geoid model was FIN2005N00, with an accuracy of 2 cm. The new FIN2023N2000 model has an accuracy of 1.4 cm.
“The requirements for the accuracy of geospatial data are constantly increasing. The new geoid model better corresponds to the modern requirements for the accuracy of geospatial data,” says Group Research Manager, NLS Finnish Geospatial Institute (FGI) , said Mirjam Birkar Koivula.
NLS is participating in the Baltic Sea geoid model BSCD2000, developed through international cooperation, to meet the needs of shipping and nautical chart creators. FIN2023N2000 has been adapted for the marine area to be compatible with the new Baltic Sea model.
The NLS geoid model is based on years of geodetic research efforts.
“In the north, tectonic movements are changing and distorting elevations, coordinates, and gravity values. To provide society with the most accurate and up-to-date elevation data, the geoid model needs to be updated,” said the senior researcher. says Timo Saari.
The previous model was used for over 10 years. Meanwhile, researchers now have access to new datasets and techniques used in new models.
“In my doctoral thesis, I studied the impact of gravity satellites and ocean gravity measurements on geoid modeling. The new model includes datasets from the GOCE and GRACE satellite missions and the Gulf of Finland Ocean Gravimetry Campaign, which It will improve the Finnish geoid model both nationally and locally,” said Saari.
The soon-to-end GeoVaPaa project, funded by the Finnish Ministry of Forestry and Agriculture, will explore how the resolution and accuracy of gravity datasets affect the accuracy of Finland’s geoid model, and how current gravity datasets are We are investigating whether this is met. Requirements set for future geoid models.
“The new geoid model provides the highest level of accuracy achievable using current datasets. The geoid model combines gravity satellites, national laser scan-based elevation models, gravity data harmonization, gravity measurements, and updated with new GPS leveling datasets,” Bilker-Koivula said.