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European Space Weather Week 2006
© NERC All rights reserved
European Magnetometer Networks and Ground Based Space Weather
MonitoringAlan Thomson
Major Themes in This Presentation:
1. Continental scale often needed to monitor space weather ground effects.
2. International co-operation is therefore essential.
3. Successful magnetometer network collaborations have operated over decades (possible ‘blueprint’ for building wider space weather networks).
4. Ever-changing technical capabilities implies that user feedback is key.
© NERC All rights reserved
Acknowledgments• Dr Jim Wild, University of Lancaster, UK (on
behalf of Prof. F. Honary, PI, SAMNET)
• Dr Ari Viljanen, Finnish Meteorological Institute, Helsinki, Finland (PI, IMAGE)
Dr Jurgen Watermann, Danish Meteorological Institute, Copenhagen, Denmark (Project Scientist, Greenland Magnetometer Array)
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The Global Context: Magnetometer Network Examples
Alaska: Geophys. Inst. Mag. ArrayCanada: CanopusRussia AE Stations: PURAESCHINA low-latitude: SMALL
TIK
CCS
DIK
1. National Geomagnetic Observatory Networks –
Issues: Regional/Global Field Modelling & Baseline Stability
2. Space Weather ‘Flavoured’ Networks:
Antarctica/Australasia: Geos. Austral.
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SAMNET• History/Development
Commenced 1st October 1987 (as a UK ‘national facility’ for STP) at 5 sec sampling Since 1995 sampling at 1 second (H, D, Z) Operated by Univ. York until 2003; Univ. Lancaster since 2003 Funding may end in March 2007 (through restructuring of UK STP science) Also stores (some) IMAGE and BGS magnetometer data at 1 second sampling
• Instruments Variometer stations equipped with fluxgates (of Ukranian and York design)
• Communications Dial-up modem (and daily processed) Only Lancaster site is real-time (for ‘Aurora Watch’
http://www.dcs.lancs.ac.uk/iono/aurorawatch/)
• Many Applications Substorm/Pi2 timing; current wedge detection/location ULF waves ‘Magnetoseismological’ study of plasma mass loading of geomagnetic field lines
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IMAGE• History/Development International Magnetospheric Study (1976); EISCAT (1982); IMAGE (1991); MIRACLE
• Instruments Fluxgates (Tromso, DMI)
• Data Rates and Communications 10 sec, some 1 sec; ISDN download per day; real time displays from host institutes Data server at FMI, which is a kind of "regional data centre". There are the following "nodes" gathering data:
TGO: 11 Norwegian sites
FMI: 10 Finnish sites (+ 1 in Norway + 1 in Estonia)
RF/Kiruna: 2 Swedish sites and SGU/Uppsala: 2 Swedish sites
GFZ/Niemegk: Hornsund (via IGF/Warsaw)
PGI/Apatity: Lovozero All contributors check their own data before FMI adds them to the final database. Data are transferred to the
nodes via internet or ISDN.
• Applications Both events and statistical studies Improved knowledge of the full 3-D ionospheric current system derived from combined magnetometer, radar
and satellite measurements
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MIRACLE: http://space.fmi.fi/MIRACLE/
IMAGE:
http://space.fmi.fi/image/index.html
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Greenland (DMI; SPRL, Univ. Michigan)• History/Development
Qeqertarsauq (1926); Qaanaq (1947); Narsarsuaq (1967)
• InstrumentsTriaxial fluxgate magnetometer (Model FGE, DMI)
• ApplicationsIonospheric current systems and external field studies (e.g. collaborations with IMAGE, MACCS (USA), CARISMA (Canada))
Greenland Magnetometry
Dotted grid geographic latitude and longitude
Dashed lines corrected geomagnetic latitude (epoch 2000.0)
Dotted line best-fit great circle (west coast stations)
Blue circles DMI variometer stations
Red circles MAGIC sites (SPRL, Univ. of Michigan)
Blue triangles DMI geomagnetic observatories
Blue diamond Sondrestrom Research Facility
Full circles data from preceding day are transmittedto DMI via modem and telephone line (presently every morning around 03 UT)
Open circles data are stored locally and sent to DMIvia snail mail (up to several months delay)
Black Roman data are transmitted to DMI in near realtime (presently every 15 min)
Courtesy of Jurgen Watermann ([email protected]) http://www.dmi.dk/projects/chain/
DMI Greenland Magnetometers
sensor type dual-core tri-axial fluxgate with main field compensationgravity-controlled gimbal system at several stations
axes misalignment < 2 mrad sensitivity 0.1 nT broadband noise (~DC – 1 Hz) long-term drift < 3 nT / year temperature drift < 0.2 nT / ºC (sensor)
< 0.1 nT / ºC (electronics) temperature resolution 0.1 ºC sampling rate 20 s and 1 s (dual acquisition system) acquisition digital, 16-bit signed integer final resolution 0.25 nT at 20-s sampling rate
0.125 nT at 1-s sampling rate time accuracy typically ±1 s (precision clock), GPS implementation under consideration data delivery delay east coast several months, west coast 1-2 months (unless telephone transmission) service interval site visit by DMI engineer once every ~5 years
Courtesy of Jurgen Watermann ([email protected]) http://www.dmi.dk/projects/chain/
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INTERMAGNET• History
IAGA discussions in 1986 (Ottawa)
Pilot project connecting US-UK in 1987 by satellite
IAGA sanctioned INTERMAGNET in 1990
Founders were US, UK, France, Canada
Key Idea = Establishing standards across the community
• Applications Global and regional
geomagnetic field modelling
Space weather studies
• www.intermagnet.org
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Summary of INTERMAGNET Operations: A Template for Space Weather Network Building
Observatory GIN
Users of definitive data;e.g. for reference
geomagnetic field models- geophysics
AnnualCD-ROM
Definitive data
Preliminary data to a GIN within 72
hours Individual research scientists,“value-added” suppliers of near-real-time data;e.g. for activity indices,
ionospheric current models – space weather science
Data transmission by satellite, email, internet
Samples at 10 seconds or faster - filtered to one-
minute values
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Practical Activities
OperationsCommittee
Data supply:GINs/Web
CD-ROM
Data formatsMeasurement
standards
Instrumentsand techniques
Applicationsto join
Technical help and training
TechnicalManual
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Intermagnet: Shaping The Future• Technical
Developments
What do users want?
1 second data feasible
Better instrumentation and communication
• Continued Observatory Network Growth Smaller scale field
variations Countries Observatories
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European SW Networks: Issues and Prospects
Existing magnetometer networks may be a template to help develop new or more extensive ground based space weather monitoring networks.
But there are questions to be asked:
• Who are the data users?
• What do they want from magnetometer or more general space-weather networks?
• What is the strength (e.g. continuity) of demand for data?
• What is the reliability and quality of data supply?
• What is the maturity/adaptability of data collection and supply?
• What technical innovations are needed/foreseen?
• Higher sampling rates; novel data dissemination methods
• ….
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Magnetometer Networks: For Space Weather Science and Applications
• The importance of near-real-time data for science & services related to space weather hazard is clear, for example, …
Magnetic activity index production (both near real time and definitive)
• e.g. in co-operation with the International Service for Geomagnetic Indices (ISGI)
‘Nowcasting’• General monitoring of magnetic conditions
• Modelling of the effects of observed geomagnetic field variations (e.g. online rapid ‘forensic analysis’ of GIC, or LEO satellite drag)
Forecasting• Many applications for geomagnetic indices & field variations
European Space Weather Week 2006
© NERC All rights reserved
Real Time Magnetograms - 2 Minute Update
Real time estimated Ap & ap - updated at
least every hour using data assimilation -
European Space Weather Week 2006
© NERC All rights reserved
BGS Real Time Magnetograms - 2 Minute Update
Real time plasmasphere monitor
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Geomagnetically Induced Currents: ‘Nowcasts’ and Forensic Analysis of Recent Events
Above: 14 July 2000 Left: 6 Nov 2001
GIC data
dB/dt data
Equivalent currents
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Summary• For the scientists who run magnetometer or ground based space
weather networks, the possibilities for developments (scientific, technical and for applications) are probably clear.
• But what do the space weather data users want in detail? This will shape how/what network scientists and technicians
actually choose to do next. For example Intermagnet would like to know if there is a user
community for 1-sec data, and what format, data communications systems are needed.
Please contact Intermagnet with your ideas: Simon Flower: [email protected].
European Space Weather Week 2006
© NERC All rights reserved
European Magnetometer Networks and Ground Based Space Weather
MonitoringAlan Thomson
Major Themes in This Presentation:
1. Continental scale often needed to monitor space weather ground effects.
2. International co-operation is therefore essential.
3. Successful magnetometer network collaborations have operated over decades (possible ‘blueprint’ for building wider space weather networks).
4. Ever-changing technical capabilities implies that user feedback is key.