Transcript Slide 1

Future Opportunities in Geomagnetism and
Electromagnetism:
The Next Decade for Geopotential Field
Research
John LaBrecque
NASA HQ
Academic Workshop on Earth Sciences
2F, Institute of Earth Sciences, Academia Sinica, Taipei
November 18-21, 2012
In 2005 NASA’s Solid Earth Science Working Group proposed a 20 year plan for Earth
Observation (solidearth.jpl.nasa.gov).
All components have been adopted by NASA with the exception of the Geomagnetic
Constellation because significant programs were underway through international cooperation.
This lapse has hurt the US geomagnetic community while advancing geomagnetism
internationally.
Two Major Challenges for
Geomagnetic Field Research
1. Relevance in today’s Earth Science
• Climate Change
• Natural Hazards Hazards
2. Data Acquistion
• Cost Effectiveness
• Aliasing and Separation of signal
sources
GRACE has managed to revive gravity field and
geodetic science by meeting these
challenges….Can we do this for Geomagnetics?
Two observatory quality geomagnetic
Satellites in 1979 (Magsat) and Oersted in
1999 provided the first accurate high
resolution information on the multidecadal secular variation and a glimpse
at the accuracy of the geomagnetic
dynamo models.
Technological advances in self-calibrating
magnetometers and GNSS remote
sensing positioning provide the
possibility for a constellation of satellite
based geomagnetic observatories for
space weather and Earth System Science.
However, the geomagnetic community
must develop a strong scientific and
societal justification for investments in
geomagnetic field research.
Magsat- 1970’s High Tech
Oersted- 1990’s Simplicity and
Effectiveness
Champ-2000’s Style and GRACE
These Satellites Revealed the
Intermediate Wavelength Geomagnetic Field
Identification of the Seafloor Spreading anomalies
helped to validate the measurement utility of the
Magsat satellite laying the ground work for future
geomagnetic satellite missions.
Swarm- A Bracelet of GRACElets
SWARM will allow us to write
the sequel …
Thirty years in the life of the
Earth’s magnetic field
SWARM Will Introduce Three Important New Concepts
to Geomagnetic Earth Observation
1.Constellation of Earth Observing Geomagnetic
Satellites for Reduction of Aliasing and
measurement of field aligned currents.
2.The introduction of new software for signal
separation and cross calibration.
3.The Vector Helium magnetometer for Cost
Effectiveness
2005-2010
2010-2015
2015-2030
2005-2010
SWARM
2010-2015
2015-2030
Magnetospheric
Ionospheric
The Last DecadeThe Decade ofand
Geopotential
Field Research
Developed
new Constellation
Geomagnetic
Measurement
Instrumentation, Programs, and Missions
Laser Input Optics
Three-Axis Coil System
Miniature Self
Calibrating Vector
Magnetometer
InGaAs Detector
RF  network
Internal 6 cm3 Helium Cell
2005-2010
2010-2015
2015-2030
Swarm is a first step in the constellation approach but what is to follow SWARM?
• Geomagnetism must identify with goals that are relevant to society and which at the
same time challenge and advance our knowledge of the environment.
• Gravity has reinvented itself through the paradigm of linking temporal gravity field
variability to mass transport.
• New geomagnetic observations should be made on ground, airborne, and
spaceborne platforms with focused attention to crustal stress change, ionospheric
TIDS, ocean circulation, and separation of sources.
• Launch the Dense Geomagnetic Constellation by 2020 with the new suite of
geomagnetic instrumentation including precision positioning and self calibrating
atomic magnetometers and non magnetic star cameras while restraining mission
creep.
Science Challenges for the Next Decade of Geopotential Field Research
• Can we constrain geodynamo models with observable phenomena Earth Surface
Phenomena?
• Can we combine geomagnetism with temporal gravity fields to better measure
ocean circulation?
• Can we utilize geomagnetic measurements to better understand crustal stress
variability?
• Can we better parse sources of Geomagnetic variability through a better separation
of sources both external and internal and the significant reduction of aliasing? Is
constellation flight the answer?
• Can we achieve geomagnetic imaging of Traveling Ionospheric Disturbances (TID’s)
or perhaps ocean tsunamis? Some resu
In Conclusion
•We must develop geomagnetic goals consistent with Environmental monitoring for
Climate Change and Natural Hazards.
•We should formulate a Second Decade for Geopotential Field Research through the
IAGA and IAG because important new opportunities do exist for both Gravity,
Geomagnetism, and Electromagnetism.
•Technology is now available to build cost effective geomagnetic microsatellite
constellations to improve temporal and spatial sampling of the geomagnetic spectrum.
Mission creep must be avoided to make 1 nT, 3D vector geomagnetic measurements
possible and cost effective.
•We must make core dynamo studies more relevant to societal interests through
stronger linkage to planetary formation and geodetic observables