International Gravity Field Service
IGFS chair: Rene Forsberg
Geodynamics
Department
Danish National Space Center
- Coordinate collection, validation, archiving and dissemination of gravity field related data
- Coordinate exchange of software of relevance for gravity field actitivities
- Coordinate courses, information materials and general public outreach relating to the earth's gravity field
The overall goal of IGFS is to coordinate the servicing of the geodetic and geophysical community with gravity field-related data, software and information. The combined data of the IGFS entities data will include both satellite-derived global models, terrestrial, airborne, satellite and marine gravity observations, earth tide data, GPS leveling data, digital models of terrain and bathymetry, as well as ocean gravity field and geoid from satellite altimetry. Both the static and the temporal variations of the gravity field will be covered by the IGFS.
IGFS is not handling gravity field data distribution directly - IGFS will function as a unifying service for the following gravity-field related IAG services - "IGFS Centres":
BGI - International Gravity Bureau - collection, archiving and distribution of gravity data
IGeS - International Geoid Service - collection and distribution of geoid models, geoid schools
ICET - International Center for Earth Tides - collection and archiving of global earth tide data
ICGEM - International Centre for Global Earth Models - distribution of satellite and surface spherical harmonic models
IDEMS - International DEM Service - Global Digital Terrain Models
IGFS Central Bureau (IGFS Technical Centre) - National Geospatial-Intelligence Agency [geodesy - G&G dept] - advise on global models, geoid and gravity, supplementing other services
IGFS currently has two working groups (EGM08 group joint with IAG Section 2):
Joint Working Group on Evaluation of Global Models (EGM08) - chairman: Jianling Huang, NRCan
Working Group on Absolute Gravimetry - Standardization and Networks - chairman: Herbert Wilmes, BKG, Germany
The IGFS was established by the International Association of Geodesy Executive Board at the General Assembly in Sapporo, Japan, August 2003, and is an IAG "level-2" service under IAG Commission 2 - Gravity Field. One of the main arguments for establishing IGFS was to provide a more focussed role of the gravity field, as one of the three fundamental pillars in IAG's first project - GGOS, the Global Geodetic Observing System. For more background information on GGOS and IGFS click here (presentation for Cairns 2005)
Another important role of the IGFS is to take initiative and coordinate international data collection projects, such as e.g. the Arctic Gravity Project, and the ongoing development of the new NGA high-resolution spherical harmonic reference model EGM06, complete to degree and order 2160.
