Mandea / Korte Geomagnetic Observations and Models

1. Auflage 2010
ISBN: 978-90-481-9858-0
Verlag: Springer Netherlands
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band 5, 344 Seiten

Reihe: IAGA Special Sopron Book Series

This volume provides comprehensive and authoritative coverage of all the main areas linked to geomagnetic field observation, from instrumentation to methodology, on ground or near-Earth. Efforts are also focused on a 21st century e-Science approach to open access to all geomagnetic data, but also to the data preservation, data discovery, data rescue, and capacity building. Finally, modeling magnetic fields with different internal origins, with their variation in space and time, is an attempt to draw together into one place the traditional work in producing models as IGRF or describing the magnetic anomalies.

Autoren/Hrsg.

Korte, Monika

Mandea, M.

Inhaltsverzeichnis

1;Foreword by the Series Editor;5
2;Contents;6
3;Introduction;8
4;Contributors;11
5;1 The Global Geomagnetic Observatory Network;14
5.1;1.1 The Network at the Time of the Sopron IAGA Assembly (August 2009);14
5.1.1;1.1.1 Introduction;14
5.1.2;1.1.2 Highlights from the Sopron IAGA Assembly in 2009;15
5.1.3;1.1.3 The Network;15
5.1.4;1.1.4 INDIGO: Better Geomagnetic Observatories at the Right Place;16
5.2;1.2 Advances in a Newly Upgraded Network: The China Earthquake Administration (CEA) Effort;19
5.2.1;1.2.1 Observatories in China: Short History Up to Twentieth Century;19
5.2.2;1.2.2 Planning the Major Upgrade: Towards INTERMAGNET Standards;19
5.2.2.1;1.2.2.1 Description of Present and Future Network;20
5.2.2.2;1.2.2.2 Criteria for Geographical Distribution;21
5.2.2.3;1.2.2.3 Instrumentation;21
5.2.2.4;1.2.2.4 Buildings: Describing the Way the Buildings are Designed and How Many Per Observatory [China Earthquake Administration, 2004 ];21
5.2.2.5;1.2.2.5 Staff: Training Level, Quantity;23
5.2.3;1.2.3 Modern Centralized Data Processing;24
5.2.3.1;1.2.3.1 A Centralized Approach;24
5.2.3.2;1.2.3.2 Data Quality Assessment: How-to;24
5.3;1.3 Filling the Gaps: Sea-Bottom Observatories;27
5.3.1;1.3.1 Rationale;27
5.3.2;1.3.2 Where to Deploy?;28
5.3.3;1.3.3 Seafloor Environments;29
5.3.4;1.3.4 Specific Solutions for Seafloor Geomagnetic Instrumentation;31
5.3.4.1;1.3.4.1 Underwater Housing of the Observatory;31
5.3.4.2;1.3.4.2 Total Field Measurement;33
5.3.4.3;1.3.4.3 Component Measurements;33
5.3.4.4;1.3.4.4 Orientation at the Seafloor;33
5.3.5;1.3.5 Shortcomings Still Preventing the Full Absolute Accuracy: How to Eliminate Them?;35
5.3.6;1.3.6 The Future of Seafloor Observatories: Where Do We Head from Here?;37
5.4;References;37
6;2 Magnetic Satellite Missions and Data;39
6.1;2.1 Introduction;39
6.1.1;2.1.1 Basic Equations;39
6.1.2;2.1.2 Magnetic vs. Gravity Field;40
6.2;2.2 Characteristics of Magnetic Satellite Data;41
6.2.1;2.2.1 Orbit, Time and Position;41
6.2.2;2.2.2 Calibration and Alignment of Satellite Data;42
6.3;2.3 A parade of Magnetic Satellite Missions;44
6.3.1;2.3.1 POGO (OGO-2, OGO-4, OGO-6);44
6.3.2;2.3.2 Magsat;45
6.3.3;2.3.3 Ørsted;45
6.3.4;2.3.4 SAC-C/Ørsted-2;48
6.3.5;2.3.5 CH48
6.3.6;2.3.6 Swarm;48
6.4;2.4 The Years After Swarm;48
6.5;2.5 Outlook: Space Magnetic Gradiometry;50
6.5.1;2.5.1 General Case: B as a Solenoid Vector Field;51
6.5.2;2.5.2 Toroidal-Poloidal Decomposition;52
6.5.3;2.5.3 Laplacian Potential Approximation;52
6.5.4;2.5.4 Magnetic Field Gradient Tensor Visualization;53
6.6;2.6 Summary;55
6.7;References;56
7;3 Repeat Station Activities;57
7.1;3.1 Introduction;57
7.2;3.2 History of Repeat Stations;57
7.3;3.3 Instruments and Procedures;59
7.3.1;3.3.1 Establishing the Position of a Station;59
7.3.2;3.3.2 Establishing the Direction of True North;60
7.3.3;3.3.3 Measuring the Magnetic Field;61
7.3.4;3.3.4 Data Reduction;62
7.4;3.4 Uses of Repeat Station Data;64
7.5;3.5 State of the Art of Repeat Station Activities;65
7.6;3.6 Conclusions;66
7.7;References;66
8;4 Aeromagnetic and Marine Measurements;68
8.1;4.1 General Introduction;68
8.2;4.2 Introduction to Aeromagnetics;69
8.3;4.3 History of Aeromagnetics;71
8.4;4.4 Data Acquisition and Reduction;74
8.4.1;4.4.1 Instrumentation;74
8.4.2;4.4.2 Fluxgate Magnetometers;74
8.4.3;4.4.3 Nuclear Precession Magnetometers;75
8.4.3.1;4.4.3.1 Proton Precession Magnetometers;75
8.4.3.2;4.4.3.2 Overhauser Effect Magnetometers;76
8.4.3.3;4.4.3.3 Optical Pumping Alkali Vapor Magnetometers;76
8.5;4.5 Survey Design;76
8.5.1;4.5.1 Flight Direction and Line Spacing;77
8.5.2;4.5.2 Survey Flight Height;78
8.6;4.6 Data Acquisition;78
8.6.1;4.6.1 Magnetic Compensation of Aircraft;79
8.7;4.7 Data Checking and Reduction;83
8.7.1;4.7.1 In-Flight Data Checking;84
8.7.2;4.7.2 Post-Flight Checking;84
8.8;4.8 Data Processing;85
8.8.1;4.8.1 Magnetic Anomaly Field Determination;85
8.8.2;4.8.2 Temporal Reductions/Corrections;86
8.8.3;4.8.3 Magnetic Leveling;88
8.9;4.9 Lithospheric Field Mapping Reference Field Correction;89
8.10;4.10 Further Processing: Micro-leveling;92
8.11;4.11 Interpolating, Contouring and Gridding;93
8.12;4.12 Conclusions for Aeromagnetics;94
8.13;4.13 Introduction to Marine Magnetics;94
8.14;4.14 History of Marine Magnetics;95
8.14.1;4.14.1 The First Attempts;95
8.14.2;4.14.2 Evolution of the Global Dataset;96
8.14.3;4.14.3 Storage and Accessibility;98
8.14.4;4.14.4 Scientific Objectives;98
8.15;4.15 Sources of Error, Evolution and Correction for Scalar Sea-Surface Measurements;100
8.15.1;4.15.1 Magnetic Observation Accuracy;100
8.15.1.1;4.15.1.1 Definitions;100
8.15.1.2;4.15.1.2 Fluxgate Magnetometers;101
8.15.1.3;4.15.1.3 Proton Precession Magnetometers;101
8.15.1.4;4.15.1.4 Optically-Pumped or Alkali-Vapor Sensors;101
8.15.1.5;4.15.1.5 Overhauser Effect Sensors;101
8.15.2;4.15.2 Ship Noise;101
8.15.3;4.15.3 Position of the Ship;102
8.15.4;4.15.4 Date and Time of the Measurement;102
8.15.5;4.15.5 Transcription Errors;102
8.15.6;4.15.6 Estimation of the External Magnetic Field;103
8.15.7;4.15.7 Estimation of the Core Magnetic Field;103
8.15.8;4.15.8 Summary of Marine Magnetic Observation Errors;103
8.16;4.16 Unusual Instruments and Processing Approaches;103
8.16.1;4.16.1 Vector Marine Magnetic Observations;104
8.16.2;4.16.2 Deep-Sea Magnetic Observations;105
8.16.2.1;4.16.2.1 Procedures;106
8.16.2.2;4.16.2.2 Some Applications;107
8.17;4.17 Conclusions for Marine Magnetics;108
8.18;4.18 General Conclusion;108
8.19;References;108
9;5 Instruments and Methodologies for Measurement of the Earth's Magnetic Field;115
9.1;5.1 Introduction;116
9.2;5.2 Fluxgate Magnetometer;116
9.2.1;5.2.1 Instrument Standards and Sources of Error;117
9.2.2;5.2.2 Fluxgate Mechanism;118
9.2.3;5.2.3 Data Collection and Telemetry;120
9.3;5.3 Declination-Inclination Fluxgate Magnetometer;121
9.3.1;5.3.1 Observing Procedure;122
9.3.2;5.3.2 Instrumental Accuracy and Sources of Error;123
9.4;5.4 Scalar (Quantum) Magnetometers;125
9.4.1;5.4.1 Background Physics;126
9.4.1.1;5.4.1.1 Polarization;126
9.4.2;5.4.2 Proton Precession Magnetometer;127
9.4.3;5.4.3 Overhauser Magnetometers;128
9.4.4;5.4.4 Time of Reading;128
9.4.5;5.4.5 Optically Pumped Magnetometers;129
9.5;5.5 Use of Scalar Magnetometers for Component Determination;129
9.6;5.6 Automated Absolute Observations;130
9.7;5.7 Other Magnetometers;131
9.7.1;5.7.1 Declinometer;131
9.7.2;5.7.2 Quartz Horizontal Magnetometer;131
9.7.3;5.7.3 Torsion Photoelectric Magnetometer;132
9.7.4;5.7.4 Kakioka KASMMER System;132
9.8;5.8 Looking Forward;132
9.9;Appendix 1: Accuracy and Baselines;133
9.10;Appendix 2: Absolute Accuracy of Scalar Magnetometers;134
9.11;References;134
10;6 Improvements in Geomagnetic Observatory Data Quality;137
10.1;6.1 Introduction;137
10.2;6.2 Quality of Recording of Geomagnetic Variations;138
10.2.1;6.2.1 Physical Principles of Variometers;138
10.2.1.1;6.2.1.1 Fluxgate Magnetometers;138
10.2.1.2;6.2.1.2 Photoelectric Feed-Back Magnetometers;139
10.2.1.3;6.2.1.3 Vector Variometers Based on Scalar Magnetometers;139
10.2.2;6.2.2 Practical Aspects of Variometer Operation;140
10.2.3;6.2.3 Quality Detection of Variometers;141
10.2.3.1;6.2.3.1 Base Line Behaviour;141
10.2.3.2;6.2.3.2 Delta-F Check;142
10.2.3.3;6.2.3.3 Inter-Comparison with Other Magnetometers;143
10.3;6.3 Quality of Secular Variation Observations;146
10.4;6.4 External Factors Disturbing Observations of the Geomagnetic Field;148
10.5;6.5 Inspection of Reported and Final Geomagnetic Data, Aims of Verification of Data;150
10.6;6.6 Metadata and Data Quality;155
10.6.1;6.6.1 What is Metadata?;155
10.6.2;6.6.2 Metadata in Geomagnetism;155
10.6.3;6.6.3 Geomagnetic Metadata Standards;156
10.7;References;157
11;7 Magnetic Observatory Data and Metadata: Types and Availability;159
11.1;7.1 Introduction;159
11.2;7.2 Data Types;160
11.2.1;7.2.1 Printed Media;160
11.2.1.1;7.2.1.1 Eye-Observations;160
11.2.1.2;7.2.1.2 Magnetograms;162
11.2.1.3;7.2.1.3 Calibration Data;162
11.2.1.4;7.2.1.4 Hourly Values;162
11.2.1.5;7.2.1.5 Magnetic Activity Indices;162
11.2.1.6;7.2.1.6 Yearbooks;164
11.2.1.7;7.2.1.7 Conservation and Conversion of Printed Media;165
11.2.2;7.2.2 Electronic Media;167
11.2.2.1;7.2.2.1 Minute Means;167
11.2.2.2;7.2.2.2 Hourly, Daily, Monthly, Annual Means;168
11.2.2.3;7.2.2.3 Digital Magnetic Activity Indices;169
11.2.2.4;7.2.2.4 One-Second Data;169
11.2.2.5;7.2.2.5 Quasi-Definitive Data;170
11.3;7.3 Data Availability;171
11.3.1;7.3.1 World Data Centres for Geomagnetism;171
11.3.1.1;7.3.1.1 World Data Centre for Geomagnetism, Edinburgh;171
11.3.1.2;7.3.1.2 World Data Center for Geomagnetism, Kyoto;172
11.3.1.3;7.3.1.3 World Data Center for Geomagnetism, Copenhagen;174
11.3.1.4;7.3.1.4 World Data Centre for Geomagnetism, Mumbai;174
11.3.1.5;7.3.1.5 World Data Center for Solar-Terrestrial Physics, Moscow;174
11.3.1.6;7.3.1.6 World Data Center for Solar-Terrestrial Physics, Boulder;175
11.3.1.7;7.3.1.7 World Data Centre for Solar-Terrestrial Science, Sydney;175
11.3.1.8;7.3.1.8 World Data Center for Geophysics, Beijing;175
11.3.2;7.3.2 INTERMAGNET;175
11.3.3;7.3.3 World Data System;176
11.3.4;7.3.4 The International Service of Geomagnetic Indices;177
11.3.4.1;7.3.4.1 LATMOS, France;177
11.3.4.2;7.3.4.2 GeoForschungsZentrum, Germany;177
11.3.4.3;7.3.4.3 Observatorio del Ebro, Spain;177
11.3.5;7.3.5 Other Data Resources;178
11.3.5.1;7.3.5.1 Space Physics Interactive Data Resource;178
11.3.5.2;7.3.5.2 Observatory Operator's Websites;178
11.3.5.3;7.3.5.3 Variometer Networks;178
11.4;7.4 Metadata and Metadata Standards;178
11.4.1;7.4.1 Magnetic Observatory Metadata;179
11.4.1.1;7.4.1.1 Yearbooks;179
11.4.1.2;7.4.1.2 INTERMAGNET;180
11.4.1.3;7.4.1.3 Metadata Standards;180
11.4.2;7.4.2 FGDC Standard;180
11.4.3;7.4.3 ISO-19115 Standard;181
11.4.4;7.4.4 SPASE Data Model;181
11.4.5;7.4.5 XML;182
11.4.6;7.4.6 Databases;182
11.5;7.5 Metadata Distribution;182
11.5.1;7.5.1 SPIDR VO (USA);183
11.5.2;7.5.2 GeoMIND (Europe);183
11.5.3;7.5.3 GEOMET (Australia);183
11.5.4;7.5.4 IUGONET (Japan);183
11.5.5;7.5.5 GeoNetwork (Open Source);184
11.6;7.6 Conclusion;185
11.7;Appendix 1: Data File Formats;187
11.7.1;World Data Centre Exchange Format;187
11.7.2;INTERMAGNET GIN Dissemination Formats;187
11.7.3;IAGA-2002 Format;187
11.8;Appendix 2: Internet Links;188
11.9;References;188
12;8 Geomagnetic Indices;192
12.1;8.1 Introduction;193
12.2;8.2 Physical Background;194
12.2.1;8.2.1 Basics;194
12.2.2;8.2.2 Electric Currents in the Magnetosphere-Ionosphere System;195
12.3;8.3 Polar and Auroral Indices;199
12.3.1;8.3.1 PC Index;199
12.3.1.1;8.3.1.1 History;199
12.3.1.2;8.3.1.2 Definition of the PC Index;202
12.3.1.3;8.3.1.3 Correlation with Interplanetary and Magnetosphere Quantities;203
12.3.1.4;8.3.1.4 Use and Misuse of PC Index;205
12.3.2;8.3.2 Auroral-Electrojet (AE) Indices;205
12.3.2.1;8.3.2.1 History;206
12.3.2.2;8.3.2.2 Definition of the AE Indices;206
12.3.2.3;8.3.2.3 Basic Characteristics of AE Indices;206
12.3.2.4;8.3.2.4 Relation with Magnetospheric and Ionospheric Physical Quantities;208
12.3.2.5;8.3.2.5 Use and Misuse of the AE Indices;208
12.3.2.6;8.3.2.6 What Next for the AE Indices;209
12.4;8.4 K Index;209
12.4.1;8.4.1 History;209
12.4.2;8.4.2 Definition of the K Index;210
12.4.3;8.4.3 The Irregular Activity as Described by the K Indices;210
12.4.4;8.4.4 Physical Meaning of K Indices;211
12.4.5;8.4.5 Use and Misuse of K Indices;212
12.5;8.5 K-Derived Geomagnetic Indices;212
12.5.1;8.5.1 History;212
12.5.2;8.5.2 Definition of the K-Derived Geomagnetic Indices;212
12.5.2.1;8.5.2.1 Kp (ap) Indices;213
12.5.2.2;8.5.2.2 am, an, and as Indices;214
12.5.2.3;8.5.2.3 a Longitude Sector Index;217
12.5.2.4;8.5.2.4 aa Index;217
12.5.3;8.5.3 Comparison Between ap, am, and aa;219
12.5.4;8.5.4 Classification of Days;221
12.5.4.1;8.5.4.1 Classification of Days as Deduced from Kp Indices;221
12.5.4.2;8.5.4.2 Classification of Days as Deduced from aa Indices;221
12.5.5;8.5.5 Relation with Solar Wind Parameters;221
12.5.6;8.5.6 Secular Variation of Geomagnetic Activity;222
12.5.7;8.5.7 Annual and Diurnal Modulations;223
12.5.8;8.5.8 Use and Misuse of K-Derived Planetary Indices;224
12.5.9;8.5.9 What Next?;224
12.6;8.6 Storm Indices;224
12.6.1;8.6.1 Dst Index;225
12.6.1.1;8.6.1.1 Definition and Method of Derivation of the Dst Index;225
12.6.1.2;8.6.1.2 Basic Characteristics of the Dst Index;226
12.6.1.3;8.6.1.3 Relationship with Magnetospheric, Ionospheric and Induced Currents;226
12.6.1.4;8.6.1.4 Use and Misuse of the Dst Index;227
12.6.2;8.6.2 ASY and SYM Indices;227
12.6.2.1;8.6.2.1 Definition and Method of Derivation of the ASY and SYM Indices;228
12.6.2.2;8.6.2.2 Basic Characteristics of the ASY and SYM Indices;229
12.6.2.3;8.6.2.3 Relationship of the ASY Indices with Magnetospheric and Ionospheric Currents;229
12.6.2.4;8.6.2.4 Use and Misuse of ASY and SYM Indices;230
12.6.3;8.6.3 Storm Sudden Commencements (ssc);230
12.6.4;8.6.4 What Next?;230
12.7;8.7 Some Other Indices;231
12.7.1;8.7.1 IHV and IDV Indices;231
12.7.2;8.7.2 Pulsations Indices;231
12.7.2.1;8.7.2.1 The Wp Index;231
12.7.2.2;8.7.2.2 ULF Indices;232
12.7.2.3;8.7.2.3 Localised PC3 Indices;232
12.8;8.8 Concluding Remarks;232
12.9;References;233
13;9 Modelling the Earth's Magnetic Field from Global to Regional Scales;238
13.1;9.1 Introduction;238
13.2;9.2 Global Modelling With Spherical Harmonics in a Shell;240
13.2.1;9.2.1 Resolution of Laplace Equation by the Fourier Decomposition Method;240
13.2.2;9.2.2 Orthogonality and Completeness Properties;242
13.2.3;9.2.3 Spherical Harmonic Expansion and Convergence Properties;243
13.3;9.3 Other Modelling at a Global Scale;244
13.3.1;9.3.1 Wavelets;245
13.3.1.1;9.3.1.1 Poisson Wavelets;246
13.3.1.2;9.3.1.2 Multi-scale Modelling;248
13.3.2;9.3.2 Localized Harmonic Functions;250
13.4;9.4 Modelling the Field Regionally;252
13.4.1;9.4.1 Review of Modelling in the Flat Earth Approximation;252
13.4.1.1;9.4.1.1 Rectangular Harmonic Analysis;253
13.4.1.2;9.4.1.2 Cylindrical Harmonic Analysis;255
13.4.2;9.4.2 SCHA and R-SCHA;256
13.4.2.1;9.4.2.1 Definition of the Domain;257
13.4.2.2;9.4.2.2 Resolution of Laplace Equation in SCHA by the Fourier Decomposition Method;257
13.4.2.3;9.4.2.3 R-SCHA as a Boundary Value Problem;259
13.4.2.4;9.4.2.4 Orthogonality Properties, Uniqueness and Completeness;261
13.4.3;9.4.3 Boundary Effects;263
13.4.4;9.4.4 Infinite Conical Domain;263
13.4.5;9.4.5 Slepian Functions;265
13.4.5.1;9.4.5.1 Slepian Functions in KL (R);266
13.4.5.2;9.4.5.2 Slepian Functions in KL (r);267
13.4.5.3;9.4.5.3 Potential Field Estimation On r;268
13.5;9.5 Conclusions;269
13.6;References;270
14;10 The International Geomagnetic Reference Field;274
14.1;10.1 Introduction;274
14.2;10.2 Scope of the IGRF;274
14.3;10.3 Inception and Development;274
14.4;10.4 Applications and Availability;275
14.5;10.5 Geomagnetic Field Components;275
14.6;10.6 Mathematical Representation;277
14.7;10.7 IGRF 11th Generation (Revised 2009);278
14.8;10.8 Global Magnetic Field Patterns;281
14.9;10.9 Limitations;281
14.10;10.10 Future;284
14.11;References;285
15;11 Geomagnetic Core Field Models in the Satellite Era;286
15.1;11.1 Introduction;286
15.2;11.2 Overview and Theory;287
15.3;11.3 Detailed Description;289
15.3.1;11.3.1 CHAOS Model Series;289
15.3.1.1;11.3.1.1 Aims;289
15.3.1.2;11.3.1.2 Technique;290
15.3.1.3;11.3.1.3 Results and Discussion;292
15.3.2;11.3.2 GRIMM Models;292
15.3.2.1;11.3.2.1 Aims;292
15.3.2.2;11.3.2.2 Techniques;294
15.3.2.3;11.3.2.3 Results and Discussion;295
15.3.3;11.3.3 BGS Models;297
15.3.3.1;11.3.3.1 Aims;297
15.3.3.2;11.3.3.2 Techniques;297
15.3.3.3;11.3.3.3 Results and Discussion;299
15.4;11.4 Conclusion;301
15.5;References;302
16;12 Interpretation of Core Field Models;304
16.1;12.1 Introduction;304
16.2;12.2 Core Dynamics and Geodynamo;305
16.3;12.3 Core Flow and High Frequency SV;306
16.3.1;12.3.1 Core Flow Inferred from Satellite Magnetic Data;307
16.3.2;12.3.2 Torsional Oscillations in the Core;308
16.4;12.4 Prediction of Geomagnetic Secular Variation;311
16.4.1;12.4.1 Mathematical Fundamentals of Data Assimilation;311
16.4.2;12.4.2 Application of Core Flow Models in SV Forecast;312
16.4.3;12.4.3 Assimilation with Simple Dynamical Models;313
16.4.4;12.4.4 Data Assimilation with Full Geodynamo Models;314
16.5;12.5 Discussion;315
16.6;References;316
17;13 Mapping and Interpretation of the Lithospheric MagneticINTbreak; Field;319
17.1;13.1 Introduction;319
17.2;13.2 World Digital Magnetic Anomaly Map;320
17.3;13.3 Impacts;321
17.4;13.4 Tectonics;325
17.5;13.5 Resource Exploration;328
17.6;13.6 Interpretation of Lower Crustal Processes;340
17.7;13.7 Summary;340
17.8;References;341
18;Index;346