The Design of GGOS in 2020

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GG S 2020
The Design of GGOS in 2020 (Chapter 9) Markus
Rothacher and many other co-authors GGOS Forum
EGU General Assembly 2007 April 17, 2007, Vienna
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Measuring and Modeling the Earths System
Measuring
Information about Earth System
Space Geodetic Techniques VLBI SLR/LLR GNSS DORIS
Altimetry InSAR Gravity Missions Terrestrial
Techniques Levelling Abs./Rel. Gravimetry Tide
Gauges Air-/Shipborne
Geometry Station Position/Motion, Sea Level
Change, Deformation
Earth System Sun/Moon (Planets) Atmosphere Ocean
Hydrosphere Cryosphere Core Mantle Crust
I N T E R A C T I O N S
C OM B I N A T I O N
Earth Rotation Precession/Nutation, Polar Motion,
UT1, LOD
Gravity Geocenter Gravity field, Temporal
variations
Influence / Modelling
Observation Modelling
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Structure of GGOS 2020 (Technical Part)
Coordination through IAG Services
Analysis, Combination, Modeling Coordination
Center(s) (IAG Services) Quality Assurance
Regional and Global Data and Product
Centers Archiving and Dissemination
Mission-specific Data and Product
Centers Archiving and Dissemination
Users Science Society
Satellite/Planetary Mission Coordination Centers
Real data information
Meta data information
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Parts of the future GGOS

• Instrumentation
• Global terrestrial networks of observatories,
  Earth observing satellites and planetary missions
• Data infrastructure
• Data transfer, communication links, data
  management and archiving systems, data and
  product dissemination centers, web pages, etc.
• GGOS Portal
• A unique access point for all GGOS products with
  a database of relevant metadata according to
  international standards.
• Data analysis, combination, modeling
• Complete and consistent data processing chains
  ranging from the acquisition and processing of
  vast amounts of observational data to its
  consistent integration and assimilation into
  complex numerical models of the Earth system.

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Integration of 5 Levels into a GGOS
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Level 4 Moon,Planets
Planets
Moon
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Ground-Based Infrastructure

• Individual Networks
• Station networks of VLBI, SLR/LLR, GNSS, DORIS
• Permanent absolute and superconducting
  gravimeters tide gauges
• Air-borne, ship-borne data aquisition
• RT data transfer new communication technologies
  for remote areas
• 30-40 Fundamental Stations
• Co-location of several techniques 1 mm local tie
  measured, additional sensors (meteo, WVR,
  ultra-stable oscillators, gravimeters,
  seismometer, tiltmeters, ), highly automated, 24
  hours a day / 7 days a week
• Latest technologies
• GNSS all GNSS, 50 Hz real-time data, 3
  receivers/antennas,
• SLR kHz, fast telescopes, two colors,
  transponders on Moon/planets
• VLBI continuous obs., new/multiple telescopes,
  real-time, obs. of (GNSS) satellites, space VLBI,
  
• Densification with GNSS stations 1000 GNSS
  stations, stable monuments

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LEOs Missions Relevant to GGOS
Already existing missions and funded future
missions
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LEO Satellite Missions

• Satellite Missions
• Continuous observations over decades, long time
  series (trends)
• Chains of satellite missions (altimetry, gravity,
  InSAR, )
• Constellations of satellites (COSMIC, SWARM, ),
  micro- and nano-satellites
• Formation flying several satellites forming one
  large instrument
• Near real-time data transfer (inter-satellite
  comm.) and analysis (early warning systems)
• Development of new sensors and technologies
  (e.g., GNSS reflectometry and scatterometry,
  laser interferometry between satellites,
  ultra-stable oscillators in space)
• Satellites allowing co-location of space geodetic
  techniques (GNSS receiver , SLR retroreflector,
  VLBI emitter, gradiometer SLR on GNSS
  satellites, VLBI in space, transponders on
  planets, )

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Processing, Analysis, Combination

• Processing and Analysis
• Fully automated processing in near real-time or
  even in real-time (early warning systems, GNSS
  seismology, atmosphere sounding, )
• Full reprocessing capabilities for all data
  available, long consistent time series for
  long-term trends
• Combination of all data types on the observation
  level
• Combination with LEO data (co-location, gravity,
  geocenter, atmosphere, )
• Combination with satellite altimetry data (and
  with InSAR ?)
• Combination with terrestrial data (e.g. gravity
  field, )
• Combination of different analysis centers
  (redundancy, reliability, accuracy, )
• Improvements in modeling, parameterization,
  conventions
• Supercomputers, visualization

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Combination Tasks and Centers (IERS/IGFS)
IERS
Ellipsoidal heights
IGFS
Physical heights, geoid
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GGOS Future Combination Space
Parameter space for a rigorous combination
Parameter Type
VLBI
GPS/
DORIS/
SLR
LLR
Alti-
GLON.
PRARE
metry
ICRF
Quasar
Coord. (ICRF)
X
(X)
(X)
Nutation
X
X
Earth Rotation
Polar Motion
X
X
X
X
X
UT1
X
X
X
X
X
Length of Day (LOD)
Coord.Veloc.(ITRF)
X
X
X
X
X
(X)
ITRF
Geocenter
X
X
X
X
Gravity Field
X
X
X
(X)
X
Orbits
X
X
X
X
X
Gravity Field
LEO Orbits
X
X
X
X
Ionosphere
X
X
X
X
Atmosphere
Troposphere
X
X
X
X
Time/Freq. Clocks
(X)
X
(X)
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4D Models of the Earth System Interactions
modified from H. Schuh
Tides of the solid Earth
Lunisolar Gravitational acceleration
Global vegetation
Oceanic tides
Ocean currents
Global ground water
Density variations in the atmosphere
Snow
Ocean loading
Atmospheric tides
Deformation of the Earth
Postglacial land uplift
Angular torques
Atmospheric loading

Angular momentum variation of the oceans
Tectonic plate motion
Angular momentum variation of the atmosphere
Volcanism
Pole tides
Earthquakes
Orientation of the Earth Precession,Nutation Pola
r motion Length of day
Gravity Field of the Earth
Effects from Earth interior