The International Geomagnetic Reference Field
(IGRF) is an standard mathematical description of the Earth's internal magnetic
field and is used widely in studies of the Earth's deep interior, its crust and
its ionosphere and magnetosphere. More information about IGRF and the coefficient
for the current release IGRF-11 can be found from IAGA V-MOD IGRF-11 web-page.
This page contains details concerning the
development of the update IGRF-11 that took place during late 2009. Candidate models
evaluations and test models are presented here.
Deadlines
- Brief notice of intent to IGRF task force
chair: August 15th, 2009
- For candidate model submissions (including model information): October 1st,
2009
- For evaluating the candidate models: November 15th, 2009
- Manuscript submissions to the EPS special issue: November 30th,
2009
- Publication online of IGRF-11: mid December, 2009
Documents
- Call for
candidate models for IGRF-11
- Report on progress towards IGRF-11 at IAGA V-MOD Meeting, Sopron, 25th Aug. 2009
- Announcement of IGRF-11 publication at AGU Fall
Meeting, San Francisco, 15th Dec. 2009
Candidate models to download (for
evaluation)
Candidate models are available in .cof format as specified in the call for IGRF-11. This contains
spherical harmonic coefficients in units of nT (or nT/yr for SV) and associated
error estimates when supplied by the authors.
A) DTU Space Team, Leader: N. Olsen
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-A-descriptions.pdf
- DGRF-2005-A
- IGRF-2010-A
- SV-2010-2015-A
B) NOAA/NGDC Team, Leader: S. Maus
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-B-descriptions.pdf
- DGRF-2005-B
- IGRF-2010-B
- SV-2010-2015-B
C) BGS Team, Leader: B. Hamilton
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-C-descriptions.pdf
- Model-C2-descriptions.pdf
(resubmission)
- DGRF-2005-C !Withdrawn!
- DGRF-2005-C2 (resubmission)
- IGRF-2010-C !Withdrawn!
- IGRF-2010-C2 (resubmission)
- SV-2010-2015-C !Withdrawn!
- SV-2010-2015-C2 (resubmission)
D) IZMIRAN Team, Leader: V. Golovkov / T. Bondar
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-D-descriptions.pdf
- Model-D2-descriptions.pdf
(late submission)
- DGRF-2005-D (late submission)
- IGRF-2010-D
- SV-2010-2015-D
E) EOST/LPGN/LATMOS/IPGP Team, Leader: A.
Chambodut
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-E-descriptions.pdf
- Model-E2-descriptions.pdf
(resubmission)
- DGRF-2005-E !Withdrawn!
- DGRF-2005-E2 (resubmission)
- IGRF-2010-E
- SV-2010-2015-E
F) IPGP/EOST/LPGN/LATMOS Team, Leader: E. Thebault
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-F-descriptions.pdf
- DGRF-2005-F
- IGRF-2010-F
- SV-2010-2015-F
G) GFZ Team, Leader: V. Lesur
Provided DGRF-2005, IGRF-2010 and
SV-2010-2015 candidate models:
- Model-G-descriptions.pdf
- DGRF-2005-G
- IGRF-2010-G
- SV-2010-2015-G
H) GSFC/JCET Team, Leader: W. Kuang
Provided only a SV-2010-2015 candidate model:
- Model-H-descriptions.pdf
- SV-2010-2015-H
Evaluations
Below are the preliminary evaluations of
IGRF-11 candidate models carried out by members of the IGRF-11 task force in October/November 2009. They are listed in
the order they were submitted. WARNING: these evaluations were not originally written for public use and may contain mistakes- they have
not been peer reviewed! They are simply the preliminary evaluations carried out prior to the decisions made by the IGRF-11 task
force on the weighting of the candidates models to produce IGRF-11 in December 2009. For a more definitive analysis the
evaluation paper by Finlay et al. (2010) to appear in a special issue of EPS should be consulted. The preliminary evaluations
are available here in .pdf form and may be downloaded by clicking on the links given.
- Evaluation
from BGS (By C. Beggan)
- Evaluation
from GFZ (By V. Lesur and M.Hamoudi)
- Evaluation
by F. Lowes (method comparison and model comparison)
- Evaluation
from IPGP (By E. Thebault)
- Evaluation
from LPGN (By B. Langlais)
- Evaluation
from IPGP (By A. Chulliat)
- Evaluation
by C. Finlay
- Evaluation
from NGDC (By S. Maus)
- Evaluation
from DTU (By N. Olsen - revised version)
- Evaluation
from NASA/GSFC (By W.Kuang/Z.Wei)
Test SV models
Test SV models
are also available for analysis. The spherical harmonic truncation degree and the number of decimal places retained
in these test models was left for the teams to decide. Some teams have also provided more than one test model, some
provided no test models. Spherical
harmonic coefficients in units of nT/yr together with error estimates where available are given in the files below in the
usual .cof format.
It is anticpated that these test models will be useful for evaluating future changes to IGRF, but they were not used in
the derivation of IGRF-11.
- SV-2010-2015-A1 : DTU test
SV model 1 (degree 13)
- SV-2010-2015-A2 : DTU test
SV model 2 (degree 13)
- SV-2010-2015-B1 : NGDC test
SV model 1 (degree 16)
- SV-2010-2015-B2 : NGDC test
SV model 2 (degree 13)
- SV-2010-2015-C : BGS
test SV model (degree 13) ! withdrawn!
- SV-2010-2015-C2 : BGS
test SV model (degree 13) (resubmission)
- SV-2010-2015-D : IZMIRAN
test SV model (degree 10)
- SV-2010-2015-G : GFZ
test SV model (degree 13)
Test models produced by robust weighting scheme
Test models derived using the robust weighting scheme
proposed by Nils Olsen are also available for analysis. It is again anticpated that these test models will be useful for
evaluating future changes to IGRF, but they were not used in the derivation of IGRF-11.
- DGRF-2005-TEST-R
- IGRF-2010-TEST-R
- SV-2010-2015-TEST-R