NATIONAL GEOMAGNETISM PROGRAM: 

CURRENT STATUS & FIVE-YEAR PLAN, 

2006-2010 

JEFFREY J. LOVE 

Open-File Report 2006-1352 

U.S. Department of the Interior 

U.S. Geological Survey 
U.S. Department of the Interior 

DIRK KEMPTHORNE, Secretary 

U.S. Geological Survey 

Mark D. Myers, Director 

U.S. Geological Survey, Reston, Virginia 2006 

For product and ordering information: 

World Wide Web: http://www.usgs.gov/pubprod 

Telephone: 1-888-ASK-USGS 

For more information on the USGS—the Federal source for science about the Earth, 

its natural and living resources, natural hazards, and the environment: 

World Wide Web: http://www.usgs.gov

World Wide Web: http://geomag.usgs.gov

Telephone: 1-888-ASK-USGS 

Suggested citation: 

Love, J. J., 2006, National Geomagnetism Program: Current Status & Five-Year Plan, 2006-

2010, USGS Open-File Report 2006-1352, Reston, VA. 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. 

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report. 

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Cover Page Explanation 

The satellite perspective map seen on the cover depicts the magnetic declination 

(degrees east) for the year 2000 as approximated by the International Geomagnetic 

Reference Field (IGRF). The black dots represent the locations of USGS 

geomagnetic observatories. The stack plot of data depicted behind the globe is of 

the horizontal component of the magnetic field recorded at USGS observatories 

during the magnetic storm of March, 12-16, 1989. 

Acknowledgments 

This report was read and approved in June 2006 by P. Patrick Leahy, Acting 

Director of the U.S. Geological Survey. 

Contributions to this document, and important support through their collective and 

cooperative efforts, have been made by Geomagnetism Program staff: 

Alan M. Berarducci, Victor Cosme-Merced, Jill E. Caldwell, Paul M. Hattori, 

Donald C. Herzog, Eric V. Murray, Leroy W. Pankratz, Karen J. Remick, Edward 

A. Sauter, Duff C. Stewart, John B. Townshend, Timothy C. White, E. William 

Worthington. 

This document has been reviewed by the leadership of the USGS, including: 

Dr. David Applegate, Senior Science Advisor for Earthquakes and Geological 

Hazards 

Ms. Carol Aten, Associate Director for Administrative Policy and Services 

Dr. John R. Filson, Scientist Emeritus and formerly the Program Director of 

Earthquake and Geomagnetic Hazards 

Dr. Anne F. Frondorf, Chief Scientist for Information 

Dr. William S. Leith, Associate Coordinator of Earthquake and Geomagnetic 

Hazards 

Dr. Jill McCarthy, Chief Scientist of the Central Region GeoHazards Team. 

This document has been reviewed by an external panel of subject-matter experts: 

Prof. Robert L. McPherron, UCLA Department of Earth and Space Sciences and 

Chairman of the Geomagnetism Program Review Panel 

Lt. Col. William B. “Trey” Cade, US Air Force Weather Agency 

Prof. Gary D. Egbert, Oregon State University, College of Oceanic and 

Atmospheric Sciences 

Dr. Stefan Maus, NOAA National Geophysical Data Center 

Dr. Michael E. Purucker, NASA Goddard and Raytheon-ITSS 

Dr. Howard J. Singer, NOAA Space Environment Center. 

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EXECUTIVE SUMMARY 

The U.S. Geological Survey’s Geomagnetism Program serves the scientific community and the 

broader public by collecting and distributing magnetometer data from an array of ground-based 

observatories and by conducting scientific analysis on those data. Preliminary, variational timeseries can be collected and distributed in near-real time, while fully calibrated, absolute time-series 

are distributed after processing. The data are used by the civilian and military parts of the Federal 

Government, by private industry, and by academia, for a wide variety of purposes of both 

immediately practical importance and long-term scientific interest, including space-weather 

diagnosis and related hazard mitigation, mapping of the magnetic field and measurement of its 

activity, and research on the nature of the Earth’s interior and the near-Earth space environment. 

This document reviews the current status of the Program, in terms of its situation within the 

Government and within the scientific community; summarizes the Program’s operations, its staffing 

situation, and its facilities; describes the diversity of uses of Program magnetometer data; and 

presents a plan for the next 5 years for enhancing the Program’s data-based services, developing 

products, and conducting scientific research. 

CONTENTS 

I. Introduction ..................................................................................................................................1 

Scientific Summary.................................................................................................................................1 

History of the Program ...........................................................................................................................1 

Current Situation ....................................................................................................................................2 

Accomplishments and Ongoing Projects ...............................................................................................2 

Challenges and Opportunities ................................................................................................................3 

II. Program Mission .........................................................................................................................4 

Government Programs, Plans, Initiatives ................................................................................................4 

International Programs and Intitiatives ...................................................................................................5 

III. Expertise and Capabilities ........................................................................................................5 

Current Staffing Situation ......................................................................................................................5 

Future Staffing Needs .............................................................................................................................6 

IV. Facilities and Operations ..........................................................................................................7 

Observatory Network .............................................................................................................................7 

Observatory Infrastructure ......................................................................................................................7 

Data Acquisition .....................................................................................................................................8 

Data Transportation ................................................................................................................................9 

Data Processing ......................................................................................................................................9 

Data Management ...................................................................................................................................9 

Data Dissemination ..............................................................................................................................10 

Facilities Management .........................................................................................................................10 

V. Partnerships ..............................................................................................................................10 

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Land and Property ................................................................................................................................10 

Observatory Operations ........................................................................................................................11 

Allied Operational Support ..................................................................................................................12 

VI. Related Programs ....................................................................................................................12 

Ground-Based Magnetometers .............................................................................................................12 

Satellite Programs ................................................................................................................................14 

Data Centers .........................................................................................................................................14 

VII. Customers ...............................................................................................................................15 

Applied Usage ......................................................................................................................................15 

Modeling and Mapping ........................................................................................................................17 

Magnetic Indices ...................................................................................................................................18 

Academic Research ..............................................................................................................................18 

Additional Applications ........................................................................................................................20 

VIII. Priorities and Progress .........................................................................................................21 

Priority Levels ......................................................................................................................................22 

Progress Levels .....................................................................................................................................22 

Program Review ...................................................................................................................................22 

Performance Measures, Goals, and Targets ..........................................................................................23 

IX. Operations and Related Development ...................................................................................23 

Observatory Network ...........................................................................................................................23 

Observatory Infrastructure ...................................................................................................................25 

Data Acquisition ...................................................................................................................................29 

Data Transportation ..............................................................................................................................31 

Data Processing ....................................................................................................................................31 

Data Management ................................................................................................................................32 

Data Dissemination ..............................................................................................................................32 

Distributed Operations .........................................................................................................................33 

X. Research and Related Development ........................................................................................33 

Research Affecting Operations ............................................................................................................33 

Analysis of Observatory Data ..............................................................................................................35 

XI. Outreach ...................................................................................................................................36 

Appendix A: Program Publications 2000 to 2005 .......................................................................37 

Appendix B: Program Abstracts 2000 to 2005 ............................................................................38 

References........................................................................................................................................39 

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I. INTRODUCTION 

SCIENTIFIC SUMMARY 

The geomagnetic field is generated by electric currents located in many 

different parts of the Earth (Parkinson, 1983; Jacobs, 1987; 1987, 1989, 

1991; Courtillot and Le Mouel, 1988). In the outer core, the main part of the 

geomagnetic field is sustained by a naturally occurring dynamo. In the 

mantle, currents can be induced by time-dependent variations in the 

ambient magnetic field. In the crust, the field has both induced and 

permanent components. Oceanic fluid currents and tides can induce 

magnetic fields. In the ionosphere and magnetosphere, electric currents are 

sustained through a complicated interaction with the Sun, the heliomagnetic 

field, and the solar wind of charged particles. The many different, and 

sometimes remote, sources of the Earth’s magnetic field each contribute to the total field at any one 

particular location, with the very different physical processes in each domain giving rise to a wide 

variety of temporal variation. Therefore, through the analysis of the time-series of the magnetic 

field from different geographic locations, the different source regions, be they below or above the 

Earth’s surface, can be studied for the purposes of scientific knowledge and understanding. 

The monitoring and analysis of the geomagnetic field is also 

important for practical applications, some of which have been in use for 

centuries. The magnetic field can be used for orientation, navigation, 

and mineral and oil exploration. Of more recent interest, the 

infrastructure and activities of our modern, technologically-based 

society can be adversely affected by rapid magnetic-field variations 

during magnetic storms, when radio communication can be difficult or 

impossible, global positioning systems can be degraded, satellite 

electronics can be damaged, satellite drag can be enhanced, astronaut 

and high-altitude pilots can be subjected to increased levels of 

radiation, pipeline corrosion can be enhanced, and electric power grids 

can experience voltage surges causing blackouts. The aurorae seen prominently at higher latitudes 

are beautiful visual manifestations of storm-time geomagnetic activity. Given the plurality of 

geomagnetic-related effects and applications, it is not surprising that the communities concerned 

with geomagnetic data are numerous and diverse. 

HISTORY OF THE PROGRAM 

The U.S. Geological Survey’s (USGS) Geomagnetism Program has, for 

many years now, monitored the Earth’s magnetic field through a network of 

observatories and conducted scientific analysis on magnetic data. The 

Program traces its origins to the Reorganization Act of 1843 in which 

Congress authorized the creation of a coastal survey agency, as part of the 

Treasury Department, that was responsible for geomagnetic surveys among 

other things. The 19th century saw the establishment of relatively shortlived magnetic stations, and the production of declination maps for the 

United States and Territories. With the purchase of Alaska, coastal surveys 

became an increasingly higher priority, and in 1889 the Coast and Geodetic 

Survey, with a Division of Terrestrial Magnetism, was established. The first 

essentially permanent geomagnetic observatories were established under the Division’s leadership 

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of Drs. Louis A. Bauer and John A. Fleming: the Cheltenham, Maryland, observatory was 

established in 1900, subsequently moved to the Fredericksburg, Virginia, site in 1956; the Sitka, 

Alaska observatory was established in 1901 and that of Honolulu, Hawaii in 1902. Soon after these 

observatories became operational, Program scientists observed that the Sitka and Honolulu 

magnetometers were also sensitive to local earthquakes, so seismometers were installed at the sites. 

In part, because of this co-location of instruments, the magnetic and seismological work in the 

Coast and Geodetic Survey were united in 1925 under the Division of Geomagnetism and 

Seismology. Over the years, the Geomagnetism Program has evolved in response to the needs of 

the country and in response to changes in the Nation’s various Federal agencies. In 1903 the Coast 

and Geodetic Survey was transferred to the newly organized Department of Commerce (DOC), and 

in 1970 the Survey became part of the National Oceanic and Atmospheric Administration (NOAA). 

In 1973 the USGS of the Department of the Interior (DOI) assumed responsibility for the National 

Geomagnetism and Seismology Programs. 

CURRENT SITUATION 

Today, Geomagnetism is one of four USGS Geologic 

Discipline Programs, in addition to the Earthquake Hazards, 

Global Seismographic Network, and Landslide Hazards 

Programs, represented by the USGS Central Region Geologic 

Hazards Team in Golden, Colorado. Geomagnetism is a selfcontained national program within the USGS, with facilities 

and personnel located in all three regions of the USGS. The 

Program has 10 full-time staff and an annual appropriation 

(FY05) of $2 million with additional reimbursable funding 

totaling approximately $0.3 million. The Program’s 14 

observatories are equipped with modern digital acquisition 

systems and are designed to produce long time-series of stable, 

one-minute-average magnetometer data having high accuracy 

and resolution. The Program collects, transports, and can 

disseminate these data in near-real time, and it also has 

significant data-processing and management capacities. The 

operational and developmental activities of the Geomagnetism Program are, in an abstract sense, 

similar to those of the Seismology Programs, which are also concerned with the treatment of timeseries of data collected from remote sites. Because of similar operational philosophies, 

opportunities for sharing infrastructure and software, and common interests in time-series and 

statistical data-analysis methodologies, the Geomagnetism Program benefits from being situated 

within the Geologic Hazards Team. From a scientific standpoint, however, the Geomagnetism 

Program retains its own specialized niche within the Team and the USGS. 

ACCOMPLISHMENTS AND ONGOING PROJECTS 

Over the past 5 years, Geomagnetism Program staff have refocused their efforts on the operations 

concerned with the magnetic observatories and the data they produce. Through the hard work of the 

staff, a number of important objectives have been accomplished. Specifically, a new observatory, 

the Shumagin geomagnetic observatory in the Aleutian Islands, has been opened. Because of its 

remote location, the installation of Shumagin was time-consuming and logistically challenging. 

This observatory fills a gap in the global geographic distribution of observatories; it is now 

producing very good data, and in the coming years it will prove to be a valuable asset for the 

Program by improving the capacity for magnetic-field monitoring. Shumagin uses the new 

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personal-computer, Internet-based, data-acquisition and transportation system, which is now being 

deployed at the other observatories as well. This new acquisition-transportation system delivers 

data in real time, and it is easier to operate and modify than the older systems. Once the data are 

received in Golden, a new in-house developed, interactive, graphical software package is used to 

process the data. The Program has a new Web site, providing more information to the public about 

operations, data, and services, along with educational and scientific material. The Program now has 

a formal memorandum of agreement (MOA) with the U.S. Air Force (USAF) concerning the nearreal-time delivery of magnetometer data, and several MOAs have been put into place concerning 

operations and different legal issues at the individual observatories. Operational and developmental 

accomplishments are documented in published papers and abstracts given in Appendices A and B. 

With respect to ongoing projects, staff are developing a number of important new operational 

components that will improve the Program’s data service. For example, the new data-acquisition 

system is being modified to produce one-second average data, and when the system is made 

operational the Program’s data will be of significantly higher temporal resolution than the current 

one-minute data. In order to improve the fidelity of acquisition systems, a coil-calibration facility is 

being installed at the Boulder observatory site, and when this is completed, staff will be able to 

carefully calibrate their magnetometers. An Oracle database is being developed that will help staff 

manage the Program’s voluminous data, serve as an interface between the data-transportation and 

processing systems, and facilitate the dissemination of data through the Program’s Web site and 

other specialized delivery tools. All of these developments will improve the quality of service to the 

scientific community and, ultimately, expand the Program’s customer base. 

Research is being pursued on magnetometer-calibration theory, data-processing theory, and the 

analysis of magnetic observatory data. The calibration and processing projects are directly related 

to the Program’s ongoing development of a coil-calibration system and the need for enhanced 

processing of observatory data, both of which are needed to improve the data quality in order to 

satisfy the ever-more-stringent needs of the user community. The data-analysis project, sometimes 

broadly described as a geomagnetic-hazard map, consists of a statistical analysis of the spatial and 

temporal characteristics of rapid magnetic-field variations, particularly those occurring during 

magnetic storms. Some of this analysis is concentrated on indices - generic measures of magneticfield activity widely used within the scientific community - while other parts of the analysis are 

concentrated on variation in the magnetic-field vector itself. Since the data-analysis project is of 

fundamental relevance to a broad range of subjects within geomagnetism, both applied and 

academic, the project will help Program staff to interface with a broad base of existing and potential 

customers. Research results are documented in Appendices A and B. 

CHALLENGES AND OPPORTUNITIES 

Geomagnetism is relevant to the broadest definition of the Earth sciences, one that encompasses the 

solid Earth, the oceans, the atmosphere, and the space environment in which the Earth resides. As a 

result, the Geomagnetism Program has opportunities to collaborate with scientists and programs 

that come from several different Federal and State agencies and a wide variety of private 

organizations and academic institutions to conduct work pertaining to the entire dimension of the 

planet and of increasing importance to our modern, technologically based society. The science of 

all of these different domains is rapidly progressing and constantly changing. In order to continue to 

serve the scientific community, then, the Program must remain abreast of developments in 

magnetometers, observatory operations, and data transportation, processing, and management. 

Scientific research and related product development must also be supported. This will enhance the 

interface with the communities using the Program’s data, ensure that observatory operation and 

data production standards are both necessary and sufficient, and will improve the profile of the 

Program. 

3
In order to take advantage of opportunities, and to succeed at attaining important internal 

objectives, the Program must be adequately supported by the bureaucratic infrastructure of the 

USGS, and it must be provided with sufficient staffing and funding. The regional and matrix-type 

structure of the USGS presents the Program with a number of challenges, because it is a national 

program with staff and facilities in all USGS regions. The Program needs to hire a few more staff, 

particularly since several are now eligible for retirement. Finally, financial resources are limited, 

but the Program has significant potential, and a modest increase in funding would dramatically 

improve the operations and enable the Program to conduct significantly more research and product 

development. 

II. PROGRAM MISSION 

The mission of the USGS Geomagnetism Program is to monitor the Earth’s magnetic field through 

an array of ground-based magnetic observatories; to provide high temporal resolution records of 

magnetic field variations covering long timescales; to disseminate magnetic data to various 

governmental, academic, and private institutions; and to conduct research into the nature of 

geomagnetic variations for purposes of scientific understanding and hazard mitigation. The 

Program is an integrated part of a network of plans and initiatives that exist within the USGS, the 

Department of the Interior (DOI), other Federal Government departments, academia, private 

industry, and the international scientific community and its organizations. 

 

GOVERNMENT PROGRAMS, PLANS, INITIATIVES 

Within the United States, the Geomagnetism Program is an integral part of the 

Federal Government’s National Space-Weather Program (Tascione, and others, 

1995). Ground-based observatories provide an effective and relatively economical 

means of monitoring the near-Earth space environment, and Geomagnetism Program 

staff coordinate their data service with space-weather programs supported by NOAA, 

the Department of Defense (DOD), primarily through the Air Force, the National 

Aeronautics and Space Administration (NASA), the National Science Foundation 

(NSF), and other governmental institutions. The Geomagnetism Program contributes the largest 

part of the ground-based monitoring effort associated with the National Geomagnetic Initiative 

called for by the National Research Council of the National Academies of Science (Brett, and 

others, 1993). The Geomagnetism Program’s mission is consistent with the DOI’s Strategic Plan

(Norton, 2003) for serving the public by advancing knowledge through scientific leadership and 

informing decisions through the application of science in order to safeguard lives, property, and 

assets. Within the USGS, the Geomagnetism Program’s mission is consistent with the objective of 

providing the Nation with reliable, unbiased information to describe and understand the Earth and 

to minimize loss of life and property from natural disasters. The Geomagnetism Program’s mission 

is consistent with the USGS Strategic Plan (Groat, and others, 2000) for describing, documenting, 

and understanding natural hazards and their risks, and since geomagnetic activity can 

adversely affect modern, technological infrastructure, the mission of the 

Geomagnetism Program is consistent with the Bureau’s recent programmatic emphasis 

on urban hazards. Finally, within the Geologic Discipline of the USGS, the 

Geomagnetism Program’s mission is consistent with the Science Strategy (Bohlen, and 

others, 1998) and its stated goals of conducting geologic hazard assessments for 

mitigation planning and for providing short-term prediction of geologic disasters and 

rapidly characterizing their effects. 

4
INTERNATIONAL PROGRAMS AND INITIATIVES 

Internationally, the Geomagnetism Program staff work closely with foreign 

national geomagnetism programs under the auspices of the International 

Association of Geomagnetism and Aeronomy (IAGA), which itself is part of the 

larger International Union of Geodesy and Geophysics (IUGG). The Program’s 

operations and research elements fall under IAGA’s Division 5, Geomagnetic 

Observatories, Surveys and Analyses, but because of the diversity of applications 

associated with magnetic observatory data, all of IAGA’s Divisions are of 

relevance to the Geomagnetism Program. The Program’s operations are closely 

linked to Intermagnet, a consortium of national geomagnetism programs having the mission of 

supporting the worldwide monitoring of the Earth’s magnetic field and the 

promotion of the usage of magnetic observatory data for practical 

applications and scientific research. The Program’s research element applies 

to the American Geophysical Union (AGU) Sections of Geomagnetism and 

Paleomagnetism, and Space Physics, and the Focus Groups of Nonlinear 

Geophysics, and Structure of the Earth’s Deep Interior (SEDI). On the very 

largest of governmental scales, the USGS is becoming more involved with 

the Group on Earth Observations System of Systems (GEOSS), a high-level 

international initiative concerned with advancing understanding of the Earth 

system across all physical and biological dimensions. The Geomagnetism 

Program’s involvement in GEOSS would also come through Intermagnet if it 

chooses to become a participating organization in GEOSS. Finally, with 

respect to notable historical international initiatives, several of the Program’s 

observatories were established in the 1950s as part of the International Geophysical Year (IGY) 

campaign, and now, some 50 years later, the Program has the opportunity to be involved with the 

International Polar Year (IPY), the International Heliophysical Year (IHY), and the Electronic 

Geophysical Year (eGY). 

III. EXPERTISE AND CAPABILITIES 

The Geomagnetism Program’s 10 full-time employees are its most important asset, and their hard 

work and contribution are deserving of recognition and support from the Leadership of the Team 

and the USGS. Addressing staffing needs is the Program’s highest priority. Most of the Program’s 

staff are in operations and development with a small research element. The tasks of all Program 

staff are mutually interdependent, and work must be coordinated and carefully planned so that the 

Program’s mission is a success. 

CURRENT STAFFING SITUATION 

Operations and Development 

The responsibilities of the Program’s operational and developmental staff can be roughly divided 

into three separate tasks: 1. Observatory operations: seven Program staff members maintain the 

existing 14 observatories, work to upgrade the data-acquisition systems at each observatory, secure 

agreements with collaborating parties at each observatory, and expand the observatory network 

when it is needed. Three of these staff are stationed in Golden, two are stationed in Alaska, and one 

each in Guam and Fredericksburg. Personnel within this task also provide magnetometer calibration 

5
services and airport compass-rose surveys. 2. Data acquisition and transportation: one Goldenbased Program staff member is responsible for developing the acquisition and data transportation 

system used by the Program. The same individual is responsible for much of the operational 

software development undertaken by the Program. 3. Data processing and management: one 

Golden-based Program staff member is responsible for processing and managing the magnetometer 

data once they are received from the observatories. Related responsibilities of these staff include 

data archiving and data dissemination. 

Scientific Research and Product Development 

One permanent Program staff member, the Group Leader, conducts research on the Earth’s 

magnetic field. In the past, most of this research has been with the internal part of the geomagnetic 

field but has gradually expanded to include the external field as well. The Program has recently 

benefited from the presence of a USGS Mendenhall postdoctoral scientist, who is working with the 

Group Leader on the statistical analysis of observatory data, a project often described as a 

geomagnetic hazards map. The Group Leader is working on a related project of mapping the 

magnetospheric equatorial ring current in space and time, a project that is fundamental to an 

understanding of storm-time, magnetic-field activity. 

FUTURE STAFFING NEEDS 

Operations and Development 

There is a great deal of technical expertise among the Geomagnetism Program’s staff, but due to 

increasingly stringent demands and expectations being placed on the Program’s data service, the 

overall technical-skill level of the Program’s operational and developmental staff mix needs to be 

continuously enhanced. With respect to specific staffing requirements, additional experience and 

abilities in electronics and computer science are a critical need. Several of the Program’s staff are 

currently eligible for retirement, and, overall, the demographics of the staff need to be factored into 

future plans in order to ensure operational continuity. Moreover, two of the Program’s observatories 

are currently manned by full-time staff members, while the remaining observatory operations are 

supported by part-time contractors. The Program will benefit from a continued transition to more 

automated operations, but hands-on involvement by experienced operational staff members is 

essential for maintaining delicate magnetometer systems. Indeed, in other similar national 

geomagnetism programs the relative numbers of technical staff devoted to observatory operations 

exceed those of the USGS. In order for the Geomagnetism Program to maintain its existing 

observatory network and to make improvements and advancements required to keep pace with 

changing demands, the Program needs to hire at least one full-time, formally trained engineer. 

Scientific Research and Product Development 

In order to make full use of the substantial and ongoing investment in observatory infrastructure 

and operational personnel, the Program needs to expand its research activities. An additional 

Geomagnetism Program research staff member would enable the Program to efficiently exploit the 

information content of the data that it is already producing and which are currently being 

successfully used by other outside agencies. The additional research activities include conducting 

basic research into the broad range of subjects within geomagnetism, developing new and useful 

products derived from the Program’s own data, and interfacing with the scientific community. In 

addition, internal use of observatory data will help with operations, by providing feedback to the 

operational staff as to the characteristics and qualities of the data being produced and, more 

generally, of their necessity and sufficiency. Specifically, the Program needs to hire one full-time 

researcher and also needs to have ongoing support for an occasional postdoctoral fellow. 

6
IV. FACILITIES AND OPERATIONS 

The primary operational and developmental responsibilities of the USGS Geomagnetism Program 

are concerned with the Program’s magnetic observatories and the data that they produce. The 

observatories support modern digital acquisition systems designed to produce long time-series of 

stable magnetometer data having high accuracy and resolution. The Program collects, transports, 

and can disseminate these data in near-real time, and it also has significant data-processing and 

management capacities. By necessity, the observatory network and everything associated with 

handling the data are technologically elaborate, consisting of many finely tuned components, each 

of which needs to be maintained and operated in careful synchronization. It is important that the 

operations be streamlined when possible, but it is also important that the operations be modernized 

and even expanded so the data service provided by the Geomagnetism Program is enhanced. 

OBSERVATORY NETWORK 

The Geomagnetism Program currently operates 14 magnetic observatories, a network that stretches 

from Guam in the western Pacific, to San Juan in the eastern Caribbean, to Barrow on the north 

shore of Alaska (see cover graphic). There are eight observatories in the lower continental United 

States (and Puerto Rico), four in Alaska, and two observatories in the Pacific. The geographic 

distribution of the Program’s observatories has been determined by the need to monitor the 

geomagnetic field on a global scale, primarily for purposes of space-weather diagnosis and main 

field modeling and mapping, as well as the practical issues of availability of land, communication 

and operational logistics, and the locations of observatories operated by other foreign-national 

programs. 

Geomagnetism Program Observatories. 

Observatory Code Latitude Longitude Established 

Barrow AK BRW 71.32 203.38 1949 

Boulder CO BOU 40.14 254.76 1961 

College AK CMO 64.87 212.14 1948 

Del Rio TX DLR 29.49 259.08 1982 

Fredericksburg VA FRD 38.20 282.63 1956 

Fresno CA FRN 37.09 240.28 1980 

Guam GUA 13.59 144.87 1957 

Honolulu HI HON 21.32 202.00 1902 

Newport WA NEW 48.27 242.88 1966 

San Juan PR SJG 18.11 193.85 1903 

Shumagin AK SHU 55.35 199.54 2003 

Sitka AK SIT 57.06 224.67 1901 

Stennis MS BSL 30.35 270.37 1986 

Tucson AZ TUC 32.17 249.27 1910 

OBSERVATORY INFRASTRUCTURE 

Most Program observatories consist of a set of temperature-controlled buildings designed to protect 

the magnetometer systems and minimize their baseline drift. Buildings housing magnetometer are 

7
made of nonmagnetic materials, and all buildings are situated on a plot of land of sufficient size, 30 

acres or more, to help insulate the operations from outside magnetic interference. The basic sensor 

package operated at each observatory consists of a triaxial fluxgate magnetometer, which gathers 

variational vectorial data, a proton magnetometer, which measures the absolute intensity of the 

magnetic field, and a theodolite, on whose telescope is mounted a small fluxgate. To preserve 

orientation, each sensor is mounted on a stable pier anchored deep into the ground. Acquisition 

systems are supported by electronic modules and computer systems. Electric power is often an issue 

at the observatories; their relatively remote locations means that power is not always stable and so 

uninterruptible power systems are installed, and some of the observatories are outfitted with backup 

generators. Because of the sensitivity of the magnetometers, artificial ground currents are a concern 

and care must also be taken in establishing electrical grounds. Finally, each observatory is served 

by telephone and satellite communication links; most of the observatories now also have Internet 

service, with Internet installation a continuing effort at the remaining sites. 

Panoramic view of the San Juan, Puerto Rico, observatory site. 

DATA ACQUISITION 

The fluxgate and proton magnetometers are operated continuously in time, with electronic dataacquisition systems producing digitally filtered, one-minute average data. Each observatory is 

visited by a Program employee or contractor once a week so that absolute measurements can be 

made using a theodolite; these data are also used for correction, during data processing, of the 

baselines of the one-minute fluxgate data. The Program’s currently operational data-acquisition 

system, or data-collection platform (DCP), has served the Program well for some 15 years or so, but 

it is now being replaced by a new more flexible, personal-computer-based, data-collection platform 

(PCDCP). This new acquisition system is being modified to produce one-second data, a substantial 

increase in temporal resolution that requires the surmounting of a number of difficult obstacles 

concerning accuracy, resolution, and timing. All of these systems rely upon a good set of magnetic 

sensors. Unfortunately, the fluxgate-sensor response function is insufficiently linear to produce data 

8
meeting some customers” stringent needs. It is for the purpose of 

measuring sensor-response nonlinearity that Program staff have 

begun to develop a coil-calibration facility at the Boulder 

observatory site. When this is made operational, Program staff will 

be able to calibrate their magnetometers so that the data can be 

acquired with improved fidelity. 

 

DATA TRANSPORTATION 

One-minute data are transmitted in near-real time to Program 

headquarters in Golden, Colorado, by a series of satellite linkages. 

This transmission system has served the Program well for many 

years now, but it is relatively delicate, being prone to interference 

from other users, and the fact that the data must be transmitted 

regularly within certain windows of time means that the data are not 

received in real time (satellite transmissions are delayed by 12 to 24 minutes). Many of these 

problems are being eliminated with the Program’s new Internet-based, data-transportation system 

(MagWorm), a modification of a highly successful system developed by USGS seismologists 

(EarthWorm). This new system allows for two-way communication between each observatory and 

Golden, it makes data-delivery essentially instantaneous, and it is extremely robust, allowing for 

real-time system reconfiguration and even brief interruption without data loss. The combination of 

the new data-acquisition system’s diagnostics and real-time two-way communication with the 

observatory will make routine operations and remote troubleshooting much more efficient 

 

DATA PROCESSING 

Fluxgate data received in Golden in near-real time are variational or “preliminary” meaning that 

they are arbitrary to within a baseline offset, which itself may have a slow drift. This raw data also 

has occasional spikes and step offsets. Absolute or “definitive” one-minute time-series are obtained 

through data processing, using specialized, in-house-developed software (MagProc). The dataprocessing software was designed using modern programming techniques and principles, and it 

provides dynamic, interactive graphical displays for the user, thus making the production of the 

Program’s final definitive data much more efficient. Preliminary variometer data are cleaned, and 

adjustments are made for fluxgate baseline drift by using the absolute measurements made with the 

proton magnetometer and theodolite. Fully calibrated, absolute time-series of magnetometer data is 

one of the flagship products of an observatory program. Unfortunately, because of the labor 

involved, absolute data cannot be produced in real time; but because of their high quality, absolute 

observatory time-series of data set the standard for ground-based magnetometer measurement. 

DATA MANAGEMENT 

An Oracle database is being developed to improve the Program’s data management capabilities, 

accommodating both the ongoing production of one-minute and the expected influx of one-second 

data. When complete, the database will be fully integrated with the data-transportation systems and 

processing software, as well as the Program’s Web site. Program staff are working to archive old 

Program data that were collected prior to routine data storage on CDs. Hourly mean data from 

Program observatories have been produced for over a century; minute data were first produced with 

the introduction of digital data-acquisition systems in 1975.

9
Current Observatory 1-Minute Data Standards. 

Magnetic resolution 0.1 nanotesla (nT) 

Temporal resolution 1 minute 

Absolute time-series accuracy 5 nT 

Variational time-series availability 12 to 24 minutes after acquisition 

Absolute time-series availability Within one year of acquisition, but often sooner 

DATA DISSEMINATION 

Program data are disseminated in two forms: variational data in near-real time, and definitive data, 

after processing and within one year of initial acquisition. Near-real-time data are disseminated to 

customers via direct links, automatic email, ftp, and increasingly over the Internet through the 

Program’s Web site. Definitive data are disseminated through CDs produced in cooperation with 

Intermagnet, which also helps promote the dissemination of magnetometer data generated by 

national programs in other countries. Program data are also available from the Intermagnet Web site 

and from the World Data Centers (described below). Program staff are working to improve the 

capacity for inspection and retrieval of both old and new data via the Program’s Web site. 

FACILITIES MANAGEMENT 

Oversight of the observatory facilities rests with Golden-based personnel from the Program and 

from the Central Region Geologic Hazards Team. This approach works well because of the day-today proximity of the personnel involved and the resulting ease of communication. But on a broader 

scale, the USGS also has a regionalized structure for facilities support, with Eastern, Central, 

Western, and Alaskan parts, and a matrix style of management, meaning that the supervisory 

structure is not parallel with the flow of money. The regionalization and matrix structures present a 

number of challenges to the Geomagnetism Program. One is simply the number of people that are 

involved. With facilities in all of the regions, Program staff must explain the purpose of facilities 

requests to each region separately, thereby increasing that effort by an amount approximately equal 

to the number of regions. Another challenge is the lack of standard operating procedures among the 

regions. So, for example, although some facility maintenance funds are available through the three 

different regions, the process of securing and spending regional funds, and even knowing how 

much funding is available, varies from region to region. Finally, the fact that some facilities are 

supported by regional staff that are relatively far removed from Program headquarters means that 

communication is inefficient. All of this adds significant complexity to the day-to-day 

responsibilities of Program staff. 

V. PARTNERSHIPS 

The Geomagnetism Program has many operational partnerships, covering a wide range of issues, 

including the usage of property, the operation of Program observatories, and the support of allied 

geophysical operation. Terms of the partnerships are formally defined through memoranda of 

agreements (MOAs). Establishing and refining these written documents have been priorities for the 

Program’s staff over the past 5 years. 

LAND AND PROPERTY 

The only Program observatories located on USGS property are Fredericksburg and San Juan. The 

Guam observatory is on property owned by the U.S. Air Force. The Sitka and Barrow observatories 

10
are on property owned by the Bureau of Land Management (BLM). The Boulder observatory is on 

property owned by the Department of Commerce’s National Telecommunications and Information 

Agency (NTIA). The Stennis observatory is on the grounds of NASA’s Stennis Space Center. The 

Del Rio and Tucson observatories are on National Park Service (NPS) property. The Fresno and 

Newport observatories are on U.S. Department of Agriculture (USDA) Forest Service (USFS) 

property. The Honolulu observatory is on NOAA property. The College observatory is on 

University of Alaska Fairbanks (UAF) property, and the Shumagin observatory is on property 

owned by the Shumagin Native Corporation (SNC). 

Aerial view of the University of Alaska’s College International Geophysical Observatory site, including the 

USGS College Geomagnetic Observatory. 

OBSERVATORY OPERATIONS 

Other cooperative agreements are concerned with the conduct on, and operational support of, the 

observatories. Specifically, the Barrow and Honolulu observatories are operated with the assistance 

of NOAA, the Stennis observatory is operated with the assistance of NASA, and the College 

observatory is operated with the assistance of UAF. The Department of Energy (DOE) provides 

some communication link support at Barrow. Program staff at the Guam observatory assist the 

NOAA tsunami warning program. The Geophysical Institute of the University of Alaska has 

assisted the Program with the construction of a coil-calibration facility currently being developed 

on the Boulder observatory site. 

11
ALLIED OPERATIONAL SUPPORT 

In addition to geomagnetic operations, some of the observatory sites support other types of 

geophysical operations. Perhaps most prominently, the College observatory is situated on the 

College International Geophysical Observatory (CIGO), which was originally designed by USGS 

Geomagnetism Program staff and which supports seismic, global positioning system (GPS), and 

infrasound operations, in addition to several different types of geomagnetism projects and 

operations. The CIGO site and the Guam and San Juan observatories support bore-hole 

seismometers of the Global Seismographic Network (GSN). The Fredericksburg and Newport 

observatories support seismometers for the USGS Advanced National Seismic System (ANSS). 

The Fredericksburg observatory site is used extensively by NOAA’s National Geodetic Survey. The 

Newport observatory supports an infrasound facility operated by the University of California under 

contract from the DOD’s Defense Threat Reduction Agency and according to the terms of the 

Nuclear Test Ban Treaty. Finally, the USGS Biological Resources Discipline (BRD) uses some of 

the buildings on the Guam observatory site. Again, these multifaceted projects are defined by 

MOAs established with the USGS and its Geomagnetism Program. 

 Summary of Operational Partnership Agencies at Each Observatory. 

USGS Partners Other Governmental Partners Other 

Observatory ANSS GSN BRD DOI 

BLM 

DOI 

NPS 

USDA 

USFS 

DOC 

NOAA 

DOC 

NTIA NASA DOD DOE UAF SNC

BRW X X X 

BOU X X X 

CMO X X 

DLR X 

FRD X X 

FRN X 

GUA X X X X 

HON X 

NEW X X X 

SJG X 

SHU X 

SIT X X 

BSL X 

TUC X 

 

VI. RELATED PROGRAMS 

GROUND-BASED MAGNETOMETERS 

Observatory Programs 

There are about 150 magnetic observatories operated world wide, producing data with various 

temporal cadences, delivery rates, and wide-ranging absolute quality. Approximately 100 of these 

observatories are part of Intermagnet and, therefore, meet common minimum operational standards. 

Most observatories are operated by governmental agencies and are situated on corresponding 

national territories and colonies. For example, the British operate observatories on Ascension Island 

and in the Falklands, the French operate observatories in the southern Indian Ocean, and the Danes 

12
operate observatories in Greenland. The most notable exceptions to this rule 

are the observatories operated in Antarctica, which is not part of any nation. 

The USGS Geomagnetism Program, with its array of 14 observatories, 

makes an important contribution to the international observatory community, 

and the Program has an important leadership role within Intermagnet. With 

respect to outreach and support, the French, British, Belgians, and Japanese 

have particularly active programs for enhancing observatory operations in 

developing nations. 

Map of the geographic distribution of Intermagnet observatories as of 2004. 

Variational Programs 

In addition to the world wide observatory network, there are a number of important variational 

magnetometer stations and arrays. Generally speaking, variational stations are not operated 

according to the same strict standards as observatories; they generally only support fluxgate or 

induction magnetometers, and there is little or no compensation for the drifting baselines of those 

instruments. The data are appropriately described as variational in that they are useful for studying 

the time-dependent variation of the magnetic field over timescales less than a day or so. Variation 

stations are often operated as parts of specific campaigns; they are not usually operated in the 

“permanent” sense of an observatory. Variation stations do not, therefore, contribute very much to 

the long-term operational efforts of government agencies; magnetic indices rely on observatories, 

not variation stations. Examples of currently operated variational arrays include the Canopus array 

in Canada, which is funded by the Canadian Space Agency; the Maccs array, also in Canada, which 

is operated by the University of Alberta, Boston University, and Augsburg College; and the 

Measure array in the Eastern United States, operated by UCLA. There also are arrays in northern 

Alaska, Europe, Greenland, and Antarctica, and along the 210 east meridian, and elsewhere. 

13
SATELLITE PROGRAMS 

Low-Altitude Satellite Missions 

There are many ongoing and proposed low-altitude satellite programs supporting space-borne 

magnetometers operated by NASA and foreign space programs (Purucker, and others, 2002). Some 

of these programs are low-altitude: Oersted, Champ, and Swarm of the European Space Agency 

(ESA), and Sac-C of NASA and the Argentine Commission on Space Activities. Since satellites 

and observatories are situated on opposite sides of the ionosphere, together they provide 

complementary data for studying this important source region for geomagnetic field variations 

(Yamashita and Iyemori, 2002; Ritter, and others, 2004). The low-altitude satellite programs are 

part of the International Decade of Geopotential-Field Research (IAGA Resolution No. 1, 1997). 

High-Altitude Satellite Missions 

Other satellite programs are high-altitude: GOES and Themis of NASA, Geotail of NASA and the 

Japanese Institute of Space and Astronautical Science (ISAS), Cluster of ESA, and Double Star of 

the Chinese Space Agency. These satellites produce data useful for monitoring and modeling the 

magnetosphere. Oftentimes the analyses are event driven, with concentrated research effort applied 

to specific magnetic storms (Kokubun, 1997; Huang, and others, 2003), where the ground-based 

observatories are used either for magnetic index calculation or, more directly, for their detailed 

magnetographic data. Although satellites provide in-situ data directly from the magnetosphere itself 

and are therefore vital for studies of magnetic storms, the global distribution of ground-based 

observatories actually provides better geographic coverage of such events. 

DATA CENTERS 

Data from most of the world’s magnetic observatories, including 

those of the USGS Geomagnetism Program, are available at the 

various World Data Centers (WDC), which are also responsible for 

preserving older photographic magnetograms: those collected prior to 

the current age of digital magnetometer data. NOAA’s National 

Geophysical Data Center in Boulder, Colorado, is geographically the 

nearest to the Geomagnetism Program headquarters in Golden, but 

the Program’s closest ongoing operational relationship is with the 

Copenhagen and Kyoto WDCs. Both Kyoto and Copenhagen have 

direct involvement with operating magnetic observatories, and both 

centers send representatives to the annual Intermagnet meetings, while the NGDC is not directly 

involved with observatory operation. Although users of observatory data can acquire them from the 

WDCs, it is worth recognizing that the WDCs are not necessarily the authoritative source for the 

data. In fact, the observatory data are not identical among the various center databases, and no 

WDC seems to have a complete set of observatory data. Some of these shortcomings are reflective 

of funding shortfalls of the centers’ home institutions. Furthermore, the WDCs are not the source of 

real-time data. Intermagnet supports a Web site that is an authoritative source for data coming from 

its participating geomagnetism programs, and although Intermagnet represents the majority of 

modern observatory programs, its membership is not complete among the wider observatory 

community. 

14
VII. CUSTOMERS 

The Program has an important and influential base of customers who rely on its data service. It is 

essential that the needs of the user community be well served, but before discussing specific 

Program goals for enhancing this service, it is worthwhile summarizing the diversity of applications 

of observatory data. Following is a partial but representative listing of current, recent, and potential 

future usage of the Program’s data, along with some representative references of the corresponding 

activities and (or) research. The Earth has one magnetic field – connecting all of the Earth’s major 

physical domains, the core, mantle, crust, ocean, atmosphere (ionosphere), and magnetosphere. As 

a result, a magnetic signal measured at one geographic location and at any particular instance in 

time is a symptom of physical processes occurring everywhere else in the world. Because of this 

continuity, it is impossible to divide the subject of geomagnetism into tidy, self-contained 

categories; the various disciplines within geomagnetism are inextricably interconnected. However, 

for organization, some categorical divisions are necessary, and this summary is structured along 

fairly traditional lines. 

APPLIED USAGE 

Geomagnetic observatory data are used for a variety of practical applications, many of which rely 

on near-real-time delivery of the Geomagnetism Program’s data. 

NOAA’s Real-Time Space-Weather Diagnostics 

NOAA’s Space Environment Center (SEC) and the U.S. Air Force 

Weather Agency (AFWA) use real-time Geomagnetism Program data for 

evaluation and forecasting of space-weather conditions (Joselyn, 1995; 

Singer, and others, 2001), a service that is important for both civilian and 

military activities concerned with hazard mitigation and even national 

security (Feynman and Gabriel, 2000). As an example, magnetic K and Kp 

indices (indices are summarized below) formed an important part of SEC 

and AFWA’s response to the potentially deleterious affects caused by rapid 

field variations during the magnetic storm of October-November 2003 

(Balch, and others, 2004). For many of these programs, continuous, realtime data delivery is essential. Other agencies involved with space weather 

diagnostics and who use USGS Geomagnetism Program data include the 

Kyoto World Data Center and National Institute of Information and Communications Technology 

in Japan, the International Service of Geomagnetic Indices in France, GeoForshungsZentrum in 

Germany, the Geological Survey of Canada, and the British Geological Survey. 

U.S. Air Force 

The Geomagnetism Program’s relationship with the U.S. Air Force 

deserves some elaboration. Since 1988, the Program has been providing 

magnetometer data from a specified set of observatories to AFWA in nearreal time and ensuring that the data stream is maintained with a specified 

degree of continuity. This service, for which AFWA compensates the 

Geomagnetism Program for costs, was formalized in 2004 with the signing 

of an MOA. Stations specifically cited in the agreement include Boulder, 

Fredericksburg, Fresno, Newport, and Sitka, along with three Canadian 

observatories and one British observatory. This service is considered to be 

15
“mission critical” to the Air Force, and there are opportunities for an enhancement of the 

relationship between the USGS and AFWA. 

Induced Currents 

Rapid variations in the Earth’s magnetic field can induce electric currents in the crust (Lanzerotti 

and Gregori, 1986; Pirjola, 2002). This can be a nuisance for the power-grid industry where the 

induced currents can find their way into power lines through ground connections. Since these 

currents are quasi-steady, they can short-circuit transformers designed for alternating current 

(Kappenman, and others, 1997; Molinski, and others, 2000). Induced currents are also a problem 

for the pipeline industries, interfering with electrical surveys of the pipelines and enhancing their 

corrosion (Boteler, 2000). Work in this subject is dominated by geomagnetism programs of nations 

at relatively high latitudes, such as Canada and Finland; but hazards associated with induced 

currents are important for the lower continental United States as well, and support for related 

research would be worthwhile. 

The Great Geomagnetic Storm of March 1989 

It is worthwhile to summarize some of the damaging effects of the great magnetic storm of March 

1989. As measured by standard planetary-scale magnetic indices (Ap=279 and Kp=9+), this storm 

was the third largest since 1932, but the real-world effects were certainly the most significant 

experienced from a magnetic storm. These have been well documented (Allen, 1989) and are 

summarized here: 

• The 21,000 megawatt Hydro-Quebec electric power-system collapsed, leaving 6 million people 

without power for 9 hours. Estimated economic impact: $300 million. Electric blackouts also 

affected large parts of Sweden. U.S. systems were affected, but not severely. If similar power 

failures had occurred in the North-Eastern United States, the economic impact has been 

estimated at $3 to 6 billion 1989 dollars (Barnes and Van Dyke, 1990). 

• Satellite orbits were disturbed, including those of the NOAA polar-orbiting satellite and the 

USAF DMSP satellite. Seven commercial satellites had considerable problems maintaining 

operational attitude, requiring manual interventions to make more thruster adjustments in one 

day than is usually required in a year. A Japanese geostationary communications satellite had 

severe problems involving a failure of half of the dual redundant command circuitry onboard. 

• U.S. Navy MARS (marine high-frequency-radio network) circuits on 10 to 20 megahertz were 

inoperable. U.S. Coast Guard reported numerous LORAN navigational problems and difficulty 

using hf-radio communications to alert users of the problems. There were numerous reports in 

Australia of hf-radio interruption. Geodetic surveys in the United States and geophysical 

surveys in Australia, Canada, and South Africa were impaired. 

• Microchip production facilities went out of production in the North-Eastern United States. 

• Magnetic declination swings of greater than 3 degrees were measured in the lower continental 

United States, thus affecting compass-based navigational systems. 

Directional Drilling 

Modern oil and gas drilling operations, in addition to drilling down into the ground, often also drill 

horizontally away from the drill rig. This reduces cost by enabling a single rig to access multiple 

reservoirs, and it can reduce the environmental impact by minimizing the surface footprint of the 

16
operations. In order to drill horizontally, however, it is necessary to know the down-hole orientation 

of the bit. This is most easily accomplished using a magnetometer loaded in an assembly that 

follows the drill bit. Measurement of the magnetic field vector and knowledge of the absolute 

declination for the site enable estimation of drill bit orientation (Thorogood and Knott, 1990; 

Lowdon and Chia, 2003). Since determination of the absolute declination is a basic product of 

geomagnetic observatories, and since declination can vary rapidly during magnetic storms, 

particularly at high latitudes, magnetic orientation for directional drilling represents a down-to-earth 

application of space weather monitoring to an issue of geological and economic importance. 

MODELING AND MAPPING 

The subject of modeling and mapping is of both applied and academic interest. In the past, the 

USGS Geomagnetism Program has been actively involved with modeling and mapping efforts, but 

because of reduced staffing levels, the Program is no longer directly involved. However, modeling 

and mapping programs continue to be important user groups of Geomagnetism Program 

observatory data.

Main Field 

Researchers use a combination of satellite and ground-based magnetic observatory data, including 

those of the USGS Geomagnetism Program, to construct models of the large-scale part of the 

Earth’s magnetic field. Two such models are the International Geomagnetic Reference Field 

(IGRF) and the World Magnetic Model (WMM) (Mandea, and others, 2000; Sabaka, and others, 

2004; McLean, and others, 2005). Satellite and observatory data are important for these efforts: 

satellites provide global coverage, although only after integration over many orbits, observatories 

provide temporally continuous coverage, although only at specific geographic sites. These are used 

in a wide variety of applications, including geographic position finding and orientation and 

academic studies of the Earth’s core, mantle, crust, and nearby space environment.

Aeromagnetic Surveys 

Air-borne measurement of crustal magnetic-field anomalies is important for geological mapping. In 

order to compensate for temporal field variations that are always present, even on magnetically 

quiet days, air-borne surveys are performed simultaneously with ground-based monitoring. Because 

of the strict operational standards of the Program’s observatories, the network can fulfill a definitive 

role in establishing baselines needed for such operations (for example, Hegmann, 2001). It has been 

proposed that a national or continental-scale aeromagnetic survey be performed so that large-scale 

geological formations can be discovered (Hildenbrand, and others, 2002), and the Geomagnetism 

Program’s observatories would play an important role in such an effort. 

Summary of USGS Stations Used in Index Calculations. 

Index Measures USGS Observatories Comment 

Dst Ring-current energy HON, SJG USGS supplies 2 of 4 sites 

AE Auroral electrojet BRW, CMO 

K Local magnetic activity BOU, FRD, FRN, NEW, SIT Under contract with USAF 

Kp Global magnetic activity FRD, SIT USGS supplies 2 of 11 sites 

Kn Northern magnetic activity FRD, NEW, TUC USGS supplies 3 of 13 sites 

17
MAGNETIC INDICES 

Like magnetic models and maps, magnetic indices are of such wide-ranging utility that it is difficult 

to characterize them as being of just operational or academic importance. The calculation of 

magnetic indices relies on ground-based observatory data. In a sense, they are like Richter-scale 

measurement of earthquakes: simple scalar measures of what are otherwise extremely complicated 

time-dependent phenomena (Mayaud, 1980; Rangarajan, 1989). Magnetic indices are generally of 

two types: range indices and absolute indices. Range indices measure the variation of the magnetic 

field, usually peak-to-peak, over a certain duration of time, typically 1 to 3 hours. Absolute indices 

measure the average value of the magnetic field, calculated over a duration of time and usually after 

a certain baseline has been subtracted. In either case, the accuracy of the indices depends on the 

quality of the data coming from their corresponding observatories. Institutions making routine 

calculation of geomagnetic indices include the Kyoto World Data Center in Japan, the International 

Service of Geomagnetic Indices in France, the GeoForshungsZentrum in Germany, and the U.S. Air 

Force. 

ACADEMIC RESEARCH 

Research in geomagnetism spans the entire frequency range of the field’s temporal variation. 

Generally speaking, academics do not require real-time data delivery. This is beginning to change, 

however, since academic research is often motivated by applied needs. Indeed, academic research 

not only increases our understanding of the Earth’s magnetic field, but it also provides new 

developments which might some day be used in operational settings. What follows is a brief review 

of academic research topics for which geomagnetic observatory data are needed. The topics are 

arranged roughly by “stratigraphy” starting from the Sun and ending with the Earth’s core. 

The Sun and Climate 

The Sun is a dynamic star, emitting a solar wind of charged particles and undergoing intermittent 

fits of stormy activity, with the likelihood of their occurrence being modulated by an 11-year 

dynamo cycle. Since the solar wind and the heliomagnetic field drive activity in the magnetosphere, 

studies of magnetic observatory records, some of which span more than a century, can be used to 

study the Sun’s long-term behavior. In fact, the observation that magnetic activity has been 

gradually increasing for over a century (Mayaud, 1972; Russell, 1975) is generally attributed to a 

long-term drift in solar activity (Stamper, and others, 1999). It is well known that changes in solar 

activity can have a measurable influence on Earth’s climate, and, therefore, long-term magnetic 

observatory records are of possible relevance to studies of global climactic trends (Friis-Christensen 

and Svensmark, 1997). There have also been recent indications of a link between magnetic activity 

and anthropogenically induced global warming (Le Mouel, and others, 2005). 

Magnetic Storm Current Systems 

Many of the studies of magnetic storms focus on the equatorial ring current, caused by the drift of 

energized charged particles trapped in the near-Earth magnetosphere (McPherron, 1995; Lu, and 

others, 1998; Daglis and Kozyra, 2002). The energy of the storm-time magnetosphere can be 

estimated by measuring and modeling the ring current, using low-latitude ground-based 

magnetometer data (Vassiliadis, and others, 1999; O’Brien and McPherron, 2000). The basic 

measure of ring-current energy is the Dst index, which relies on four observatories, two of which 

are USGS Geomagnetism Program observatories. Other studies are concerned with the broader 

storm-time circuit of magnetospheric-ionospheric electric currents, including field-aligned and 

auroral-zone electrojet currents (Iyemori, 1990; Cade, and others, 1995; Clauer, and others, 2003). 

The basic measure of auroral-zone magnetic activity is the AE index, which relies on a high18
latitude necklace of observatories, two of which are USGS observatories. The subject of storm-time 

current systems is integral both to academic studies of the magnetosphere and to real-time space 

weather diagnostics (described above). 

Quiet-Time Ionosphere 

As the Earth rotates under the Sun, ionospheric winds are generated through differential heating. 

These winds flow past the geomagnetic field, thereby generating electric currents which, in turn, 

generate their own magnetic fields. Through photoionization, solar irradiance also causes an 

enhancement of the ionospheric electrical conductivity on the day side. As a result, the magnetic 

field measured at an observatory exhibits a daily variation, the solar-quiet (Sq) variation most easily 

seen during nonstorm time periods (Campbell, 1989). There is less research being conducted in this 

field than there is in storm-time current systems. Nonetheless, in order to study the current systems 

of magnetic storms, it is important to be able to subtract an Sq baseline from storm-time 

magnetograms. This, in turn, requires that the observatories produce data with minimal instrumental 

drift.

Oceanic Induction 

The motion of a conducting fluid through a magnetic field induces currents. Magnetometer data 

can, therefore, be used to measure ocean flow since ocean water is electrically conducting. NOAA’s 

Atlantic Oceanographic and Meteorological Laboratory use a combination of voltage data collected 

from sub-ocean telecommunication cables and USGS Geomagnetism Program data to measure the 

oceanic fluid transport off the coast of Florida (Larsen, 1992). Induced electric currents are also 

driven by oceanic tides (Maus and Kuvshinov, 2004), and electric currents induced during magnetic 

storms can have an affect on observatory data (Olsen and Kuvshinov, 2004). 

Crustal and Mantle Conductivity 

Since time-dependent variation of the magnetic field can induce currents in the electrically 

conducting solid Earth, long time-series of absolute-baseline (definitive) data produced by magnetic 

observatories can be used to estimate crustal and mantle electrical conductivity. This helps to 

constrain the composition and tectonic structure of the Earth (Egbert and Booker, 1992, Constable, 

1993, Weiss and Everett, 1998; Fujii and Schultz, 2002). The study of crustal and mantle 

conductivity is the primary motivation behind the proposed magnetotelluric component of the 

National Science Foundation’s Earthscope initiative. 

The Earth’s Core 

Absolute-baseline data produced by ground-based observatories, such as those operated by the 

USGS Geomagnetism Program, are useful for studies of the Earth’s core, where fluid motion not 

only sustains the geodynamo but also causes the magnetic field to exhibit a slow secular variation 

(Jackson, and others, 2000). Because of core motion, the declination at the Earth’s surface changes 

by about 0.2 degrees per year. Such a drift, when integrated over time, is sufficient to be easily 

measured, even with a simple compass. Analysis of the large-scale form of the magnetic field and 

its time dependence can be used to discover fluid motion in the core (Bloxham and Jackson, 1991), 

to constrain the angular-momentum budget of the Earth’s differential rotation (Hide and Dickey, 

1991), and to learn about the geodynamo (Roberts, 1992). 

19
ADDITIONAL APPLICATIONS 

Following are additional applications of ground-based magnetometer data, for which the USGS 

Geomagnetism Program’s basic one-minute data product is of insufficient temporal resolution to 

make a substantial contribution. With the development of its one-second acquisition system, the 

Program will be expanding its data services to customers working in some of these subjects. 

However, for some needs, subsecond (~100 Hz) acquisition cadence is required, and this will 

require the installation of induction-coil type magnetometers. Generally speaking, the long-term, 

continuous collection of high-frequency data, such as that needed for the projects described below, 

represents an important developing frontier for the ground-based observatory community and for 

the USGS Geomagnetism Program in particular. 

Magnetospheric Waves and Pulsations 

The geomagnetic field can sustain waves or pulsations, manifest on magnetograms as quasisinusoidal oscillations having frequencies ranging from about 1 mHz to 10 Hz (Samson, 1991; 

Hughes, 1994). These waves are often associated with magnetic storms and recently have been used 

for monitoring the integrated plasma density of the magnetosphere (Green, and others, 1993). The 

Japanese are leading an effort to make operational the routine monitoring of pulsations for purposes 

of space-weather diagnostics (Nose, 1998). Ideally, this would rely upon one-second data collected 

at various stations around the globe, including, quite critically, across the continental United States, 

Hawaii, Guam, and Puerto Rico. 

Lightning 

The Earth’s ionosphere resonates in response to electromagnetic impulses (Sentman, 1995). With 

an array of induction magnetometers widely distributed across the globe and measuring these socalled Schumann resonances, the location of individual lightning flashes can be found anywhere 

around the globe (Fullekrug, and others, 2000). Since the ionosphere resonates at about 8 Hz, these 

locations could, conceivably, be accomplished in near-real time. It also means that data acquisition 

systems must operate at about 100 Hz or better so that lightning locations could be determined with 

some useful accuracy. Should the USGS employ such a system, it would be of obvious interest to 

the meteorological and climatological communities, and collaboration with NOAA would be 

sensible. 

Volcanoes and Earthquakes 

It has been well established that large earthquakes and volcanic eruptions produce locally 

measurable electromagnetic effects, after and possibly during the event (for example, Johnston, 

1997). Research on this subject is supported by the USGS Earthquake and Volcano Hazards 

Programs using arrays of data-acquisition systems located near the region of activity. There is little 

capacity within the Geomagnetism Program to be actively involved with these efforts since the 

Program’s observatories are simply too wide-spread to provide anything more than data from a 

single site that might happen to be near a center of activity. On the other hand, on a global scale, the 

pressure pulse associated with earthquakes and volcanoes can establish gravity waves in the 

ionosphere that can be detected with magnetometers very far from the source region (Weaver, and 

others, 1969; Mueller and Johnston 1989), and this is a subject of interest to the USGS. 

Nuclear Explosions 

As with volcanic eruptions and earthquakes, the pressure pulse associated with 

atmospheric nuclear explosions sets up gravity waves in the ionosphere and these can be 

manifest on magnetograms (Burch and Green, 1963). Electromagnetic waves are also 

20
produced by nuclear explosions; these propagate around the Earth in the ionospheric wave 

guide at the speed of light. Magnetometer systems are not currently part of the suite of 

sensors covered by the Comprehensive Test Ban Treaty (CTBT), but they do have the 

potential to make a contribution. Should such a program be undertaken, it would be 

consistent with the seismic CTBT contribution already being made by the USGS. 

Summary of Data Requirements of Various User Groups. 

Usage Real-Time Need Quality Resolution needed 

Space Weather Diagnostics Yes Variational min and sec 

Induced Currents Yes Variational min and sec 

Directional Drilling Nearly real-time Absolute min 

Main-field Mapping and Modeling No Absolute month and year 

Aeromagnetic Mapping and Modeling Yes, during surveys Variational min and sec 

Sun and Climate No Variational, Absolute hour, day, month, year 

Storm Current Systems No Variational, Absolute min and sec 

Ionosphere No Absolute min 

Ocean No Absolute min and hour 

Crust and Mantle No Absolute sec, min, hour 

Core No Absolute month and year 

Magnetospheric Pulsations Yes, for operations Variational 0.0001-100 Hz 

Lightning Yes, for operations Variational 0.1-1,000 Hz 

Nuclear Explosions Yes, for operations Variational 0.1-1,000 Hz 

VIII. PRIORITIES AND PROGRESS 

In order for the Geomagnetism Program to continue to serve the scientific community, it must 

adapt to changing needs. For the sake of efficiency and to ensure success, it is important that 

proposals for change be made in such a way that they represent a continuous and logical extension 

of the work already being performed by Program staff and that make use of the capacities that 

already exist within the Program. Therefore, insofar as providing data is the Program’s most 

important service, then additional developments would be built upon this basic foundation. If the 

scientific community needs better data, then operational standards should be raised. If the 

community needs better geographic coverage of magnetic field monitoring, then additional 

observatories should be opened. If the community needs higher-frequency sampling, then dataacquisition systems should be modified. In each case, however, the establishment of goals, and the 

planning needed to attain those goals, must be made with an awareness of what is appropriately 

done by the Program, what needs to be done for the scientific community, and what, realistically, 

can be done with the financial resources and the personnel skills that exist within the Program or 

can be obtained. 

A similar philosophy applies to research and the development of related products. Given that 

the Program’s operations are centered on the observatories and their data, proposals for research 

should focus on the use of those very same observatory data. Such work would enhance the 

Program’s working relationship with existing customers, and it would help to demonstrate the 

utility of the data to potential users, thus helping to expand the Program’s customer base. In-house 

usage of the data would also provide immediate, internal feedback on the suitability of the data for 

the user community. In response, then, to the staff’s own awareness of the quality of the data, 

operational issues could be addressed immediately if they were found to be wanting. All of this 

must be tempered, however, with realistic expectations as to the scope of the proposed research. 

21
Since the research element within the Geomagnetism Program is small, and the diversity of uses for 

observatory data is so extremely broad, research projects will, by necessity, be relatively 

specialized. That being said, they should be expected to be of high quality and have the effect of 

enhancing the profile of the Program. 

PRIORITY LEVELS 

Following is a set of priority levels, established in response to recommendations made by an 

external review panel. The three different priority levels are intended to summarize the importance 

for accomplishing a certain objective within the next 5 years given its role within the 

Geomagnetism Program’s larger mission. 

Priority Level A: These objectives are of fundamental importance to the existing primary mission 

of the Program. The objectives may be vital for an important customer or the community, or they 

may have been established by some well-defined mandate. 

Priority Level B: These objectives are generally consistent with, but not necessarily of 

fundamental importance to, the Program’s existing primary mission. 

Priority Level C: Although these objectives might be of practical or scientific importance, they are 

not part of, nor are they particularly related to, the existing primary mission of the Program. 

PROGRESS LEVELS 

Following is a set of progress levels, established along the lines of those used for other USGS 

Program 5-year plans. The three different progress levels are intended to summarize the likelihood 

that a certain task will be accomplished within the next 5 years, given the difficulty of the task and 

the availability of funds and staff time. 

Progress Level 1: At current level of support, these objectives can be achieved within 5 years, even 

if they require concerted effort. This progress level indicates that sufficient resources, funding, and 

worker time, are known to be available. 

Progress Level 2: Notable progress is expected to be made on these objectives within 5 years, but 

progress will be slower than optimal due to constraints on, or uncertainties about, required 

resources. 

Progress Level 3: Little or no progress is expected to be made within 5 years because of 

insufficient resources or because the objectives do not have short-term guarantees of success. 

PROGRAM REVIEW 

The entire Program, along with this 5-Year Plan, has been reviewed by an external committee 

during fiscal year 2005. The Program is regularly represented at annual Committee for Space 

Weather (CSW) meetings held in collaboration with other related Federal agencies and which 

functions as part of the interagency National Space Weather Program. The Geomagnetism Program 

performs an important data-delivery service to the U.S. Air Force Weather Agency. This service is 

reviewed annually according to terms of a Memorandum of Agreement between the AFWA and 

the USGS. Within the international scientific community, the Program’s operational standards and 

22
developments are reviewed, in conjunction with those of other national geomagnetism programs, 

through Intermagnet. Program magnetometer data are regularly reviewed by external Intermagnet 

associates for quality and consistency. Workshops and meetings organized by IAGA help ensure 

that Program operational standards are maintained at a high level, consistent with those of other 

national geomagnetism programs. 

PERFORMANCE MEASURES, GOALS, AND TARGETS 

The Geomagnetism Program contributes to the DOI Strategic Goal of Serving Communities, the 

USGS Hazards Mission Goal to “Provide science ... focusing efforts to predict and monitor 

hazardous events in near-real time and to conduct risk assessments to mitigate loss.” Under the 

Government Performance Results Act of 1993, the Geomagnetism Program has been tracked and 

reported under the "Number of formal workshops or training provided to customers" measure by 

USGS. In 2003; the Geomagnetism Program was reviewed by the White House Office of 

Management and Budget (OMB), together with the other USGS geologic hazards programs 

(Earthquake Hazards, Volcano Hazards, Landslide Hazards, and Global Seismographic Network), 

using the Performance Assessment and Management Tool (PART). The programs were rated by 

OMB as “Moderately Effective.” At the same time, new PART performance measures were 

developed for these programs, which are currently being tracked and reported on by USGS, 

including an Efficiency Measure for both Geomagnetism and Global Seismographic Network. 

Summary of End Outcome Measures Intermediate or PART Measures/Part Efficiency or Other Outcome. 

Fiscal Year 2005 Plan 2005 

Actual 

Change 

from 2005 

2006 

Enacted 

Change 

from 2005 

2007 

Request 

Change 

from 2006 

Workshops or training sessions 1 2 +1 1 -1 0 -1 

Data processing and notification costs 

(thousand of dollars per gigabyte) 0.99 0.79 +0.63 1.42 +0.63 1.33 -0.09 

IX. OPERATIONS AND RELATED DEVELOPMENT 

The USGS Geomagnetism Program will acquire, transport, process, manage, and disseminate 

geomagnetic data collected in the United States and its territories, and it will work 

cooperatively with related programs in performing such tasks in order to support hazard 

assessment, risk reduction, scientific research, and public education. 

Since magnetometer data are the Program’s most fundamental and useful product, the dataacquisition and data-treatment infrastructure must be maintained and enhanced so that the 

Program’s existing customer base is well served and new customers added. 

OBSERVATORY NETWORK 

South Pole observatory 

Install and cooperate on the operation of an absolute magnetic observatory at the South Pole. 

Priority B: An observatory has been operated at the South Pole in the past, and the last absolute 

measurements were made in 1971. A South Pole observatory would, because of its remote location, 

be of high profile and is consistent with the existing primary mission of the Geomagnetism 

23
Program. It is reasonable to assume that, should a South Pole observatory be installed, the data it 

produced would be widely used within the scientific community. 

Progress 2: The South Pole currently has a number of variometers, and their data could be used, 

together with periodic absolute measurements (not made at the moment), to produce definitive, 

absolute-quality time-series. The highly qualified workers at the site could be easily trained to make 

the absolute measurements. Collaboration would make accomplishing this objective easier. One 

current Geomagnetism Program staff member has experience working at the Byrd magnetic 

observatory, and the South Pole supports a Global Seismographic Network (GSN) station, so it is 

regularly visited by a Central Region Geologic Hazards Team staff member or contractor. Funding 

for the project could come from the NSF, possibly as a result of USGS involvement with the 

International Polar Year (IPY). There have been some discussions on the matter with potential 

collaborators, but a formal proposal has not yet been submitted. 

Additional Alaskan observatories 

Install and cooperate on the operation of additional absolute magnetic observatories on the 

North Slope of Alaska. 

Priority B: This proposal is of obvious political complexity. Insofar as drilling horizontally allows 

multiple reservoirs to be accessed from a single rig, support for directional drilling programs can be 

considered to be a practical means of minimizing the negative impact on what is a sensitive natural 

environment. This project is consistent with the existing primary mission of the Program. It is 

reasonable to assume that, because of widespread interest in magnetic activity at high latitudes, the 

data would be widely used within the scientific community. 

Progress 2: Geomagnetism Program staff have significant experience working in Alaska: four 

Program observatories exist in Alaska, and two full-time staff are normally stationed in Fairbanks, 

thus facilitating work in the region. The Program also has a close working relationship with the 

Geophysical Institute of the University of Alaska Fairbanks, and some upgrade of their variometer 

station at Kaktovik would be a logical step toward reaching this objective. If a decision is made to 

commence with this project, then a 

Some funding for this 

project could also conceivably come from the NSF, possibly as a result of USGS involvement with 

the IPY, especially if it is found that the research scientific community has particular interest in the 

observatory and if they have operational needs that differ from the directional drilling industry. This 

project has been discussed with possible collaborators in the oil-drilling support industry. 

Cooperative Research and Development Agreement (CRADA) 

might be considered, a means by which the USGS and private industry are allowed to enter into a 

legal working relationship and where funding is appropriately focused. 

Mexican observatories 

Assist with the upgrading, expansion, and operation of magnetic observatories in Mexico. 

Priority B: The Mexican geomagnetism program operates one observatory at Teoloyucan, which 

was recently welcomed into Intermagnet. The program has enthusiastic staff and they have received 

support from the Belgians, Danes, and from the USGS. Insofar as more observatories are needed on 

a global scale, then Mexico represents a logical frontier for expansion. Additional observatories in 

the Yucatan or Baja could make important contributions to studies of the equatorial ring current. 

Assisting the Mexicans with their program is consistent with the existing primary mission of the 

USGS Geomagnetism Program. 

24
Progress 3: No specific projects are currently being discussed in detail. Funding opportunities 

might be found through international agencies, and some contacts might be established through the 

Pan American Institute of Geography and History (PAIGH), with which Program staff already have 

been associated. 

Midway observatory 

Install and operate a new magnetic observatory on the Pacific island of Midway for a 

minimum of one solar cycle. 

Priority B: The Geomagnetism Program operated an observatory on Midway from 2000 to 2002; 

and one was operated before that from 1964 to 1966. Data from a Midway observatory would find 

application with scientists engaged in studies of the main field and the equatorial ring current. This 

project is consistent with the existing primary mission of the Program. 

Progress 3: Geomagnetism Program staff found that the Midway observatory was generally 

difficult to install and operate during the years 2000 to 2002. The island is only inhabited by a few 

employees of the Fish and Wildlife Service (FWS) and their contractors and partners. As a result, 

securing a reliable observer for making absolute measurements was and would be a challenge. 

Flights to and from the island are relatively infrequent, making operations logistically difficult. 

Rainfall can be heavy, and drainage is a problem since the island is virtually flat; the Program’s 

observatory stopped operating in 2002 after the site was flooded. Working from experience, these 

problems can be solved with some redesign of a Midway observatory. At present, however, there is 

no known source for paying for a Midway observatory other than directly with Program funds. But 

since the Pacific has so few observatories, data from a Midway observatory would be useful, and 

support might come from the space weather community. 

OBSERVATORY INFRASTRUCTURE 

Maintenance and renovation 

Maintain and renovate existing observatory infrastructure, concentrating on fixes that reduce 

long-term maintenance needs and costs. 

Since many of the Geomagnetism Program’s observatories were established decades ago, some of 

the buildings are in need of repair and replacement. In general, maintenance of the observatory 

infrastructure is becoming more expensive and labor intensive, but by modernizing operations and 

making quality repairs, this burden could be reduced in the future. 

Barrow 

Make substantial renovation of the Barrow observatory infrastructure. 

The Barrow observatory is the Geomagnetism Program’s most northerly site, recording the active 

magnetic-field variation characteristic of high latitudes. The observatory is important for 

measurement of the auroral electrojet, and data are used to calculate the AE index. The site is also 

important for main-field modeling, because the secular variation of magnetic declination is 

relatively rapid at high latitudes. Barrow is likely to be useful in the future for directional drilling 

operations, should the nearby National Petroleum Reserve, Alaska, located west of Prudhoe, be 

opened more completely to the oil industry for exploration and extraction. The observatory is 

located on 100 acres, one of the few pieces of Federal Government property on the north shore (a 

BLM withdrawal). 

25
Priority A: Conditions at Barrow can be very harsh, with winter temperatures sinking to -50 

degrees Celsius and winds reaching 100 km/hour. Therefore, it is not surprising that the buildings 

have suffered some degradation since their installation; some were installed as long as 55 years ago. 

All of the buildings need substantial carpentry and electrical repairs, and some should be replaced 

outright. The buildings are drafty and their interiors need better temperature control. Until fixes are 

made, fluxgate baselines are drifting more than at most other observatories. This degrades the realtime data and necessitates intensive processing to produce absolute time-series. 

Progress 2: There are no known funds available for building replacement; therefore, fairly 

extensive efforts are underway to re-side building exteriors. Most of the needed funding for 

repairing the Barrow buildings will come through the Western Region facilities office, although 

those monies might, in the end, be insufficient to support all the needed work. The difference will 

have to come from Program funds because meeting this objective is consistent with the existing 

primary mission of the Geomagnetism Program. Program staff are investigating creative solutions 

to financing the project, but nothing of certainty has developed. 

Winter at the Barrow observatory.

Fredericksburg

Transfer a portion of the Fredericksburg observatory site to NOAA and make substantial 

renovation of the remaining observatory infrastructure. 

Because the Fredericksburg observatory and its predecessor at Cheltenham have been in operation 

since 1900, the data time-series are of importance for a wide variety of research projects addressing 

long-term, global-scale phenomena. Fredericksburg data are used extensively by NOAA and the 

U.S. Air Force for space-weather diagnostics, and they are used for the calculating the K and Kp 

indices. Fredericksburg is a classic old-style observatory, located on 187 acres of beautiful Virginia 

countryside. Most of the facilities on the Fredericksburg site date from its establishment in 1956, 

including several operational buildings, extensive office space, a machine shop, a large coil26
calibration facility, and two houses. The site was extensively used by dozens of staff members 

when operations were more labor-intensive than they are today and when the headquarters of the 

Geomagnetism Program was located in Fredericksburg. Today, six of the buildings are used by 

NOAA’s National Geodetic Survey (NGS). The ANSS uses one of the buildings for a seismometer, 

and the remaining buildings are used by the Geomagnetism Program. One full-time Program 

employee is stationed at Fredericksburg, working as an observer and on maintenance.

Priority A: Since their construction, the Fredericksburg buildings have not been modernized, and 

in particular, electrical systems are antiquated. Several of the buildings need substantial carpentry 

repairs, and some should be replaced outright, although all building foundations are in good shape. 

The building interiors need better temperature control. Until complete fixes are made, fluxgate 

baselines are drifting more than at most other observatories. This degrades the real-time data and 

necessitates intensive processing to produce absolute time-series. 

Progress 2: Discussions are currently underway to transfer ownership of all buildings not used by 

the USGS to the NGS. Doing so will reduce the maintenance workload of Program staff. Attention 

will then be focused on repairing the buildings used for geomagnetic operations. There are no 

known funds available for building replacement; therefore, fairly extensive efforts are underway to 

re-side building exteriors. Most of the needed funding for repairing the Fredericksburg buildings 

will come through the Eastern Region facilities office, although those monies might, in the end, be 

insufficient to support all the needed work. The difference will have to come from Program funds 

since meeting this objective is consistent with the existing primary mission of the Geomagnetism 

Program. 

Panoramic view of the Fredericksburg observatory site. 

OBSERVATORY IMPROVEMENTS 

Improve observatory infrastructure so that data quality and data delivery are enhanced. 

As with maintenance and renovation, this is a complicated and multifaceted issue that will be 

addressed in more detail in a separate document. The summary here is relatively brief, highlighting 

only the most important issues. 

27
Magnetometer baselines 

Priority A: A basic measure of the state of the observatory facilities is the stability of the fluxgate 

baselines. Since fluxgate magnetometers are temperature sensitive, it is important that the building 

housing the fluxgates be well insulated and have thermostatically controlled heating. By addressing 

this problem at a number of observatories, the quality of data produced by the Program will be 

improved and the labor-intensive data processing required to produce absolute time-series will be 

reduced. 

Progress 1: Program staff are already making progress on this objective. New temperature 

buildings are being erected at the Fresno observatory, and improved temperature controls have been 

installed at Barrow and Fredericksburg. Buildings still need to be installed at Del Rio and Stennis. 

Fortunately, most of this objective concerns the Program’s lower latitude observatories, which 

present more hospitable working conditions. Funding for this project is being borne directly by the 

Program since it impacts upon the Program’s existing primary mission. 

Internet links 

Priority A: In order to operate the Program’s new data-transportation links, each observatory must 

have Internet links. Once these are installed and once the transportation system is operable at a 

given observatory, then data can be delivered in real time. Additionally, Internet links allow 

personnel in Golden and elsewhere to communicate with the observatory’s acquisition system, 

thereby facilitating remote troubleshooting and the updating of software. All of this will make staff 

time more efficient. 

Progress 1: Program staff are making good progress on this objective, but a few of the 

observatories, such as Barrow, Del Rio, and Tucson, are going to be more difficult to outfit with 

Internet links because of their relatively remote locations. Funding for this project is being borne 

directly by the Program since it impacts upon the Program’s existing primary mission. 

Cooperative agreements and sharing of facilities 

Explore opportunities for sharing observatory sites with allied geophysical programs. 

The Geomagnetism Program’s observatory network is a substantial physical asset; the network is 

widespread, and each observatory site consists of buildings on a large piece of controlled and 

relatively secure property having communication links and other basic support. The observatory 

sites could support more co-located geophysical operations. 

Priority A: By cooperating and sharing the observatory sites with other allied geophysical 

programs, ongoing operations can be further supported and direct costs to the Geomagnetism 

Program can be reduced. The Program’s existing partnerships have already been summarized 

herein. The following is a discussion of potential partnerships on specific observatories. 

San Juan 

Progress 2: The San Juan observatory is situated on 120 acres of property, and Geomagnetism 

Program staff are currently exploring sharing some of this area with NOAA for the establishment of 

an elaborate meteorological facility. Spacious and underutilized San Juan office space might be 

shared with Water Resources Division (WRD) of the USGS and with the newly proposed USGS 

expansion of Caribbean seismic stations as part of the President’s tsunami initiative. 

28
Sitka 

Progress 2: The Sitka observatory is situated on 118 acres of Forest Service (USFS) property, and 

Geomagnetism Program staff are currently exploring sharing some of this area with NOAA for the 

establishment of an elaborate meteorological facility. 

DATA ACQUISITION 

New data-acquisition system 

Complete deployment of the new data-acquisition system at all observatories. 

Priority A: The Program’s new data-acquisition system (PCDCP) is producing very good oneminute average data. The system is more flexible, allows for Internet links, and also appears to be 

more robust than the older system (DCP). The new system is being modified for one-second 

acquisition. 

Progress 1: Program staff have made good progress on this objective, and about half of the 

observatories now support the PCDCP. This objective is well within the Program’s existing primary 

mission, and funding and staff time are being borne directly by the Program. There is no significant 

obstacle preventing full deployment in the near future. 

One-second magnetic data 

Complete testing, refinement, and standardized operational deployment of one-second dataacquisition systems at all observatories. 

Priority A: Many new space-weather research and diagnostic programs being developed by 

governmental and academic agencies rely on real-time, pulsation analyses of high-frequency, 

ground-base magnetometer data. The 1-second data systems will expand the Program’s customer 

base in this important and rapidly developing field. 

Progress 1: Program staff time is the most critical issue affecting progress, but they have already 

been making a concerted effort on this objective and now have a mastery of the technicalities 

involved in producing one-second data that meets or even exceeds the standards for time-stamp, 

filtering, and resolution set by the user community. The Program will benefit by comparing their 

systems and data with those of other Intermagnet observatory programs and the various variometer 

programs. 

Magnetometer response 

Correct for the nonlinear response function of each observatory fluxgate magnetometer so 

that data fidelity is improved. 

Priority A: Unfortunately, the fluxgate magnetometers used by the Geomagnetism Program have a 

nonlinear response function; this causes the data to exhibit occasional step offsets. The problem can 

be, at times, difficult to detect, but it is cause for concern. The Program’s variational data do not 

now meet accepted standards for resolution when the occasional offsets are manifest. Because the 

offsets can be removed with data processing, the Program’s final definitive data do meet accepted 

standards. The nonlinear response became apparent upon comparison of vector intensity differences 

between the fluxgate and proton magnetometers operated in parallel at each observatory. It is 

probable that other geomagnetism programs, those not making such interinstrument comparisons, 

29
are afflicted with similar, but undiscovered, problems. Nonetheless, Program staff recognize that 

the problem must be fixed at USGS observatories. 

Progress 1: The majority of the nonlinearity in the fluxgate magnetometer response function can be 

traced to a digital-to-analog converter. The first priority for resolving the problem is to directly 

measure some constants associated with the converter. These constants then need to be introduced 

into software that will adjust the raw data so that the response of the system is made more linear. 

The only issue affecting progress on this matter is staff time, but this objective should be 

accomplished within the timeframe of this 5-year plan. 

Coil-calibration facility 

Complete coil-calibration facility at Boulder so that magnetometer systems can be checked 

and calibrated prior to deployment. 

Priority B: In order to check the linearity of the Program’s fluxgate magnetometers, the coilcalibration facility on the Boulder observatory site needs to be completed. Work on this facility, one 

of the most important for the Program, represents an awareness of the necessity that the data be of 

the highest possible quality. 

Progress 2: The Program has already benefited substantially from cooperation with the 

Geophysical Institute of the University of Alaska Fairbanks, where the coils were built. Staff have 

also been working with a smaller version of the coil system, one developed and installed at College 

observatory. The nonorthogonality of the coil system needs to be measured and electronic dataacquisition systems need to be installed and tested. The Program will benefit from collaboration 

with allied programs, including the geomagnetism program of Canada where a similar facility is 

already in use. 

Magnetotelluric data 

Outfit the observatories in the contiguous United States for electric-potential measurements. 

By measuring the ground electric potential, along with the magnetic field, at a given geographic 

site, the electrical conductivity of the crust and mantle below that site can be estimated. The longer 

those measurements are made, the deeper the profile of the estimate. This is an important physical 

quantity for understanding the tectonic dynamics of the Earth’s surface and interior. It is notable 

that an extended magnetotelluric survey was conducted on the Tucson observatory from 1932 to 

1942 when that observatory was still operated by the Carnegie Institution, and similar 

measurements have been made at a few other observatories for more brief periods of time. 

However, these measurements are not currently being made at any of the USGS observatories. 

Priority B: The observatory sites are ideally suited for long-term magnetotelluric measurements, 

and such a project would enhance the usage of Program data, including the magnetic data already 

being collected, by researchers in what is traditionally a geological discipline. 

Progress 2: Outfitting the observatories for making the Earth-current measurements requires the 

installation of two pair of widely separated electrodes and some modification of the Geomagnetism 

Program’s new data-acquisition system. A larger commitment would be necessary if data are to be 

collected continuously over a long period of time and if it is required that the data be made 

available in real time. Some Program staff already have experience in collecting magnetotelluric 

data. A Program proposal to obtain funds necessary to support these operations has been submitted 

to Earthscope. A decision is pending. 

30
High-frequency induction-coil data 

Outfit a wide-spread subset of the Program’s observatories with high-frequency magnetic 

induction-coil data-acquisition systems. 

Priority C: Monitoring for lightning and nuclear explosions, and more generally, conducting 

research on the ionospheric Shumann resonances, is presently outside of the Program’s existing 

primary mission. Involvement would, however, add significantly to scientific and social relevance 

of the Program and the USGS. Lightning is an important atmospheric phenomenon, and nuclear 

explosion monitoring is, of course, a subject of critical importance for national security. 

Progress 3: In order to collect the high-frequency data, an entirely new magnetometer system must 

be used. Its operation will require the development of new software, especially if the data are to be 

reported continuously, for long periods of time, and in real time. For global-scale studies, the 

observatories of Guam, San Juan, and College would be suitable sites, with their wide separation 

allowing for event location through triangulation. Collaboration with outside agencies and institutes 

could help to facilitate this project. At the moment, no funding is available, but the possibilities are 

obviously enormous. 

DATA TRANSPORTATION 

Operational Internet delivery 

Make fully operational the Internet transportation of observatory data. 

Priority A: The Geomagnetism Program is now transmitting data from a number of its 

observatories via the Internet. But most customers, in particular the U.S. Air Force, are receiving 

real-time data from a stream received in Golden through the older satellite data-transportation links. 

Since the satellite links will be phased out in the future, and since this will probably occur in stages, 

with some satellite links brought down before others, a transition must be initiated to make 

operational the reception and subsequent dissemination of the Internet data streams already in 

place. 

Progress 1: Substantial Program staff effort has been devoted to developing and deploying the 

Internet data-transportation system. Now, this important capacity needs to be moved to a fully 

operational stage. There is no significant obstacle to accomplishing this objective in the very near 

future. 

 

DATA PROCESSING 

Software 

Complete testing, refinement, and make publicly available in-house-developed, dataprocessing software. 

Priority A: For several years now, the Geomagnetism Program has been developing specialized 

software (MagProc) that can be used for cleaning, adjusting, and combining absolute data with 

variational time-series, so that absolute “definitive” magnetometer time-series can be published. 

Sharing the software will be welcomed by the wider observatory community, assisting programs 

that survive with relatively lean funding and staffing support, especially those in developing 

countries. 

31
Progress 1: Program staff are preparing for the release of the software now, and supporting 

documents are under preparation. There is no significant obstacle to accomplishing this objective in 

the very near future. 

DATA MANAGEMENT 

Oracle database 

Complete the development, testing, installation, and full integration of an Oracle database. 

Priority A: The Geomagnetism Program must be able to manage its existing one-minute data and 

the larger influx of one-second data, and therefore, an Oracle database is being developed. For 

efficiency, the database needs to be fully integrated with data-transportation, data-processing, and 

data-dissemination software. Obviously, this objective is well within the Program’s existing 

primary mission, and indeed, it represents an important component in the continuity of Program 

operations. 

Progress 1: Program staff and contractors have already made good progress on the developmental 

part of this objective, but additional work is needed and operational testing has not yet begun. 

Specialized training has been undertaken by Program staff, and success depends on their continued 

and concerted, hands-on effort. Some Program funds are needed to support contractors, but the 

most important resource needed to meet this objective is staff time. 

Old Program data 

Complete the assembly and in-house archiving of the Program’s old, one-minute, one-hour, 

monthly, and yearly average data. 

Priority A: Hourly mean data from Program observatories have been produced for more than a 

century, and one-minute digital have been produced since 1975. Yet, the Program has only a partial 

compilation of these data, and the World Data Center compilations are incomplete and somewhat 

inconsistent. Since Program staff have an authoritative understanding of their own data, it is 

important that users of the data be able to obtain the data, and expert insight on their nature, directly 

from the Program. This will benefit the scientific community by enhancing understanding of the 

data themselves, and it will help the Program interface with the data-user community. 

Progress 1: Program staff have assembled all available one-minute digital data, but the one-hour, 

monthly, and yearly data still need attention. There is no significant obstacle to accomplishing this 

objective in the very near future. 

DATA DISSEMINATION 

Web-site interface 

Complete testing, refinement, and installation of an enhanced data-display and data-retrieval 

tool for the Program’s Web site. 

Priority A: The Internet is now a primary means of disseminating information, and it is vital for 

the future of the Geomagnetism Program that its Web site tools for data display and data retrieval 

be upgraded substantially in order to facilitate the usage of Program data, and as a result, improve 

the service provided by the Program. The Program also needs to have a quick, one-page graphical 

32
summary of recent and current magnetic field activity. This should be updated in real time on the 

Web site. 

Progress 1: Program staff and contractors have already made substantial progress in developing the 

Web-site tools. Some development remains; capacities for one-second data have not yet been 

initiated, and they still need to be tested in an operational setting. Some Program funds are needed 

to support contractors, but the most important resource needed to meet this objective is staff time. 

DISTRIBUTED OPERATIONS 

Make real-time, Internet data deliveries to select users directly and separately from each 

observatory, independent of any intermediate Golden reception and transmission. 

Priority C: Data could be delivered in real time through a distributed observatory system, with data 

transmitted to users directly from each observatory through the Internet. Should the links to Golden 

be interrupted, data could still be received because each observatory would be operating 

independently. The system, as a whole, would be robust since it is unlikely that all, or even several, 

observatories would ever go off-line simultaneously. 

Progress 3: Geomagnetism Program staff have not worked on this objective directly, but in 

principle, with the ongoing development of Internet-based transportation and delivery systems, 

there is no substantial obstacle to achieving this objective. The U.S. Air Force might be interested 

in supporting this effort, but no specific proposal has been made. 

X. RESEARCH AND RELATED DEVELOPMENT 

The USGS Geomagnetism Program will conduct scientific research and develop related 

products that will enhance the quality of the Program’s data and that can be used for 

purposes of hazard assessment, risk reduction, scientific research, and public education. 

RESEARCH AFFECTING OPERATIONS 

Magnetometer filters and data averaging 

Determine phase lag, resolution, and accuracy of one-second average data. 

Priority A: In producing one-second average data, multiple subsecond samples are passed through 

an analog Butterworth filter for purposes of antialiasing. A one-second average datum is then 

constructed by applying a digital Gaussian filter, centered on the time stamp, to the subsecond 

samples. The combination of these filters introduces phase lag and affects the resolution and 

accuracy of the final one-second data. These issues need to be quantitatively analyzed so that 

Program staff can appropriately adjust their filter parameters and so that the final data product can 

be more precisely presented to the user community. 

Progress 1: The basic starting point here is the construction of a one-second equivalent of the 

current one-minute filtering system, something that is detailed in the Intermagnet users” manual. 

However, the combined effects of Butterworth and Gaussian filtering, which is certainly a desirable 

operational pairing, must be stated more clearly. Obtaining a consensus among one-second-data 

users as to their specific needs is also required. The issue here is something of a loose end for the 

33
entire observatory community, and because of a lack of staff time, progress on this objective has 

not been as fast as desired. Still, the objective should be easily accomplished within a year or so. 

Coil-calibration system 

Determine unknown nonorthogonality parameters of the Program’s new coil-calibration 

system, and correct for their effects so that magnetometer nonlinear response can be easily 

measured. 

Priority A: In order to study the response of the Program’s complete 

fluxgate magnetometer acquisition system, and thereby ensure that the 

Program’s data are of high fidelity, completing the Boulder triaxial 

calibration facility is a high-priority objective. The primary unresolved 

issue needing the attention of Program research staff is the determination 

of the coil’s nonorthogonality parameters. Until these are determined, 

system measurements using each of the three separate coils will be 

contaminated by an unknown amount of cross-talk. An important issue 

concerns the ability to determine a unique set of parameters given different 

inversion methods. Once complete, the facility will be useful to other 

outside programs and should, therefore, enhance the service provided by 

the Program. 

Progress 2: The primary issue of nonorthogonality has been essentially resolved (for example, 

Merayo, and others, 2001; Primdahl, and others, 2002), but the theory needs to be put into a form 

useful for Program staff and the specific problem at hand. The Program will benefit from 

collaboration with allied geophysical programs, including that of the geomagnetism program of 

Canada, which already has a similar facility, and possibly also with universities and private 

industry. Unfortunately, because of lack of staff time, progress on this objective will not be as fast 

as desired. Funding for this project is being borne directly by the Program since it impacts upon the 

Program’s existing primary mission. 

Magnetometer rotation and nonorthogonality 

Develop a method for estimating small unknown rotational and nonorthogonality parameters 

for the Program’s operational fluxgate magnetometers in place at each observatory. 

Priority B: In practice, it is impossible to align a fluxgate with the north-south or magnetic 

meridian, and all multiaxial fluxgates have some degree of nonorthogonality. These issues affect 

data quality, but they are often conveniently ignored within the observatory community, in part 

because the issue is so difficult to resolve. It is possible that the absolute data collected at each 

observatory could be used to determine, or at least constrain, rotational and orthogonality 

parameters that could then be incorporated into data processing to produce a superior definitive, 

time-series product. In an abstract sense, this project is related to the Program’s development of its 

coil-calibration facility; the orthogonality parameters of the coil must be determined. Therefore, in 

some ways this objective must precede that coil-facility objective. Hence the higher priority 

assigned here. 

Progress 2: Some lessons might be drawn from the satellite magnetometer calibration studies (for 

example, Luhr, and others, 2000; Risbo, and others, 2003), where calibration parameters are often 

determined after the satellite has been put into orbit using a combination of satellite orientation and 

fluxgate vector and proton intensity data. As of now, only a reconnaissance study on this issue has 

been performed, and the theory needs to be put into a form useful for Program staff and the specific 

34
problem at hand. An important issue concerns the ability to determine a unique set of parameters. 

Because of lack of staff time, progress on this objective will not be as fast as desired. 

Near-real-time definitive data 

Use enhanced data-processing methods to make definitive, or nearly definitive, data available 

in near-real-time. 

Priority C: Many users now need estimates of absolute magnetic data in near-real time; of 

particular importance is magnetic declination, which is used for navigation and directional drilling, 

and a refinement of the real-time estimation of the K index would be valuable to space-weather 

operations. An investigation needs to be made to determine if the current data processing capacities 

can be made more real time, possibly using dynamic recursive least-squares methods that have 

already been demonstrated in other contexts (for example, Teunissen, 2001) and possibly also using 

more sophisticated interpolation functions such as splines. 

Progress 3: Only a reconnaissance study has so far been undertaken on this subject, and although 

there is some cause for optimism, specific results have yet to be obtained. This is a wide-open 

subject, and much work remains to be done. 

ANALYSIS OF OBSERVATORY DATA 

Magnetic K-index and delta-B analyses 

Perform a statistical analysis of magnetic K indices and minute-to-minute changes in the 

magnetic field, characterizing those statistics in terms of the temporal and geographic 

nonstationarity. 

As the first part of a multifaceted study, the statistics of magnetic K and Kp indices, characterized 

in terms of simple mathematical functions, is needed so that gross magnetic activity can be 

probabilistically predicted. The analysis would need to account for the fact that the statistics of 

magnetic indices is nonstationary both temporally and geographically. A reconnaissance search 

through the literature finds relatively few studies of the occurrence statistics of K and Kp indices; 

the modern abundance of data needs to be more fully exploited. The second part of the study would 

concentrate on the more complicated vectorial observatory data themselves, characterizing the 

statistics of minute-to-minute differences (delta-B) in the magnetic field (for example, Viljanen, 

and others, 2001; Weigel and Baker, 2003). Finally, the two studies need to be brought together, 

with an analysis of the relationship between the range indices and the spectral content of delta-B. 

This particular objective is actually a logical first step in what has sometimes been described as a 

“magnetic hazard-map” analysis. Once field activity is characterized by statistical functions, the 

parameters of these functions can be adjusted to geographically interpolate between observatory 

positions, thereby yielding a continuous function that can be displayed on a map and used for more 

general, global-scale depiction of field activity. 

Priority A: This type of study is not necessarily real time, but it would help to put real-time activity 

into a meaningful context. It is expected that this analysis will be of interest to the U.S. Air Force, 

NOAA, and the electric power-grid industry. 

Progress 1: Since the arrival of a USGS Mendenhall postdoctoral fellow, good progress has been 

made on this objective. Concentration has been on the Kp index, and the analysis of its recurrence 

statistics modeled as a Poisson process; preliminary inspection of the delta-B data indicates that 

they occur in statistics according to an exponential distribution. An abstract has been given at a 

35
space-weather conference and another has been submitted. Work will continue with the near-term 

goal of writing a definitive paper on the subject, something that, because of its fundamental nature, 

is bound to be highly cited. 

Magnetic ring-current and Dst analyses 

Perform an analysis of Dst and the spatial structure and temporal evolution of the equatorial 

ring current, utilizing data from numerous midlatitude magnetic observatories. 

The traditional measure of magnetic-storm energy is the Dst index, which measures the equatorial 

ring current and which is constructed from data from four midlatitude observatories, including the 

USGS observatories of Honolulu and San Juan. Today, there are about 30 observatories suitable for 

analysis of the equatorial ring current, making it possible to study in detail the structure and 

evolution of the current system. Of interest are the current’s magnitude and symmetry and how 

these quantities change over the duration of a magnetic storm. Some work on this subject has 

already been conducted (for example, Clauer and McPherron, 1974), but further analysis is needed, 

depicting results in ways that are easily understood and exploiting the abundance of modern data. 

Priority B: This type of study could eventually become a real-time operationally diagnostic 

product. The U.S. Air Force has recently shown an increased interest in Dst, what with no domestic 

organization making its routine calculation. It is expected that the analysis proposed here will be of 

interest to the USAF, NOAA, and academic scientists, and would, more generally, help the 

Geomagnetism Program interface with an important subset of the observatory-data-user 

community. 

Progress 2: An equatorial ring-current map has already been constructed for two storms that 

occurred in October and November of 2003. This map is spatially and temporally dependent, 

constructed by fitting a truncated Fourier series to the distribution of horizontal intensities from 

various midlatitude observatories at different moments in time over the duration of each storm. 

Results were presented at a recent space-weather conference, and a publication on the subject is 

now in preparation. 

XI. OUTREACH 

In order to enhance its service to the scientific community, the USGS Geomagnetism Program 

will communicate and work with users of observatory data. 

Priority A: Since the range of applications of observatory data is very broad and since the needs of 

the various groups using observatory data are different, it is important that Geomagnetism Program 

staff communicate and work regularly and directly with the outside user community. This objective 

is also related to similar needs on the part of almost all observatory programs and, indeed, even 

Intermagnet. Meeting this objective will enhance the usage of observatory data and improve the 

profile of all geomagnetism programs, including that of the USGS. 

Progress 1: There are few obstacles to attaining this objective. The Geomagnetism Program 

could, itself, host a users’ meeting in Golden. The venue is obviously attractive, and speakers and 

other participants could be invited to attend using their own external funds. A meeting of this type 

could include a tour of the Boulder observatory, thus providing feedback to Program staff. The 

meeting could also be coordinated with the annual Intermagnet meetings and possibly also with the 

Space Weather Week conference put on by the Space Environment Center of NOAA. 

36
APPENDIX A: PROGRAM PUBLICATIONS 2000 TO 2005 

2005 

Love, J. J., 2005. Magnetic equator, in World Book 

Encyclopedia, M, 55. 

2004

Love, J. J., 2004. Book review of Earth’s Magnetism in the 

Age of Sail, by A. R. T. Jonkers, Phys. Earth Planet. Inter., 

147, 354-364, doi:10.1016/j.pepi.2004.05.004. (Invited) 

2003 

Love, J. J. and Constable, C. G., 2003. Gaussian statistics for 

palaeomagnetic vectors, Geophys. J. Int., 152, 515-565, 

doi:10.1046/j.1365-246X.2003.01858.x. 

Tauxe, L. and Love, J. J., 2003. Paleointensity in Hawaiian 

Scientific Drilling Project Hole (HSDP2): Results from 

submarine basaltic glass, Geochem. Geophys. Geosyst., 4, 

doi:10.1029/2001GC000276. 

2002 

Kopytenko, Y. A., Serebrianaya, P. M., Nikitina, L. V. and 

Green, A. W., 2002. Recent investigations of 

electromagnetic variations related to earthquakes, J. 

Geodynamics, 33, 489-496. 

Love, J. J., 2002. Geodynamo, McGraw-Hill Encyclopedia of 

Science and Technology, Vol. 8, 16-18. 

Worthington, E. W. and Love, J. J., 2002. Geomagnetic field 

monitoring at Barrow, Alaska, Climate Monitoring and 

Diagnositics Laboratory, NOAA, U.S. Dept. Commerce, 

26, 166-170. 

2001 

Townshend, J., 2001. Fifty years of monitoring geophysical 

data at Barrow, Alaska, in Fifty more years below zero (Ed: 

Norton, D. W.), The Arctic Institute of North America, 

University of Alaska Press, Fairbanks. 

2000 

Gubbins, D., Barber, N. C., Gibbons, S. and Love, J. J., 2000. 

Kinematic dynamo action in a sphere: I Effects of 

differential rotation and meridional circulation, Proc. R. 

Soc. Lond., A, 456, 1333-1353. 

Gubbins, D., Barber, N. C., Gibbons, S. and Love, J. J., 2000. 

Kinematic dynamo action in a sphere: II Symmetry 

selection, Proc. R. Soc. Lond., A, 456, 1669-1683. (Invited) 

Love, J. J., 2000. Statistical assessment of preferred 

transitional VGP longitudes based on paleomagnetic 

volcanic data, Geophys. J. Int., 140, 211-221. 

Love, J. J., 2000. Paleomagnetic secular variation as a 

function of intensity, Phil. Trans. R. Soc. Lond., A, 358, 

1191-1223. 

Love, J. J., 2000. On the anisotropy of secular variation 

deduced from paleomagnetic volcanic data, J. Geophys. 

Res., 105, 5799-5816. 

Love, J. J., 2000. Dynamo action and the nearly axisymmetric 

magnetic field of Saturn, Geophys. Res. Lett., 27, 2889-

2892. 

Love, J. J., 2000. Book review of Paleomagnetic Principles 

and Practice, by L. Tauxe, AGU EOS, 81, 172. (Invited) 

Macmillan, S. and Quinn, J. M., 2000. The 2000 revision of 

the Joint UK/U.S. Geomagnetic Field Models and the IGRF 

candidate model, Earth Planets Space, 52, 1149-1162. 

Macmillan, S. and Quinn, J. M., 2000. The derivation of the 

World Magnetic Model 2000, Brit. Geol. Surv. Tech. Rept. 

WM/00/17R. 

IAGA Division V, Working Group 8, [Including Program 

member Quinn, J. M.], 2000. International Geomagnetic 

Reference Field, 2000; Phys. Earth Planet. Inter., 120, 39-

42, Pure Appl. Geophys., 157, 1797-1802, Geophys. J. Int., 

141, 259-262. 

37
APPENDIX B: PROGRAM ABSTRACTS 2000 TO 2005 

2005 

Love, J. J. and Green, J. C., 2005. Time-dependent mapping of 

storm-time ring-current structure, AGU EOS, 86, GP31A065. 

Remick, K. J., and Love, J. J., 2005. Modelling of wait times 

between storm-level Kp occurrences, AGU EOS, 86, 

SM13A-0316. 

Love, J. J., 2005. Intermagnet and USGS magnetic 

observatory operations, Space Weather Week, NOAA SEC, 

www.sec.noaa.gov/sww/index.html. (Invited) 

Remick, K. J. and Love, J. J., 2005. Statistics of changes in the 

1-minute geomagnetic H component at Newport, Space 

Weather Week, NOAA SEC,

www.sec.noaa.gov/sww/index.html. 

Remick, K. J. and Love, J. J., 2005. Occurrence frequencies of 

large storms: A method for statistical prediction, GEMCEDAR Workshop, http://cedarweb.hao.ucar.edu. 

Love, J. J., 2005. Intermagnet and USGS magnetic 

observatory operations, Workshop on utilization of 

seismographic networks within the Global Earth 

Observation System of Sytesms, (Invited) 

2004 

Berarducci, A. M., Pankratz, L. W. and Stewart, D. C., 2004. 

The new USGS PC based data collection platform, 

Sociedad Geologica Mexicana, Reunion Nacional, IV, 163. 

Love, J. J., 2004. Continuous calibration of ground-based 

magnetic-observatory fluxgate magnetometers, AGU EOS, 

85, F656. 

Pankratz, L. W., Sauter, E. A. and Stewart, D. C., 2004. 

PCDCP: An Update 2004; IAGA workshop on geomagnetic 

instruments, data acquisition, and processing, Kakioka and 

Tsukuba, Japan, 11, 47. 

Sauter, E. A., Stewart, D. C., White, T. C., Townshend, J. B., 

Worthington, E. W. and Shipman, G. K., 2004. USGS 

Magnetometer Calibration Facility at Boulder Observatory, 

IAGA workshop on geomagnetic instruments, data 

acquisition, and processing, Kakioka and Tsukuba, Japan, 

11, 27. 

Stewart, D. C., Pankratz, L. W., Sauter, E. A., and Hanych, D. 

B., 2004. MagWorm: A Geomagnetic Data Acquisition and 

Processing System, IAGA workshop on geomagnetic 

instruments, data acquisition, and processing, Kakioka and 

Tsukuba, Japan, 11, 100. 

2003 

Love, J. J. and Walker, M. R., 2003. Critical bifurcations 

among viscous boundary layers of the geodynamo, AGU 

EOS, 84, F549. 

2002 

Berarducci, A., 2002. USGS magnetic observatory on Midway 

Atoll, IAGA workshop on geomagnetic instruments, data 

acquisition, and processing, Hermanus, South Africa, 10, 

16. 

Worthington, E. W., Sauter, E. A. and St. Louis, B. J., 2002. 

USGS fluxgate magnetometer calibration system, IAGA 

workshop on geomagnetic instruments, data acquisition, 

and processing, Hermanus, South Africa, 10, 23. 

2001 

Green, A. W., 2001. Rationale for ocean bottom geomagnetic 

observatories, IAGA-IASPEI, Hanoi, Vietnam, G5.02, 237. 

Herzog, D. C., 2001. Diagnostic software for magnetic 

observatory and field survey operations, IAGA-IASPEI, 

Hanoi, Vietnam, G5.01, 234. 

Herzog, D. C., 2001. Windows-based magnetic observatory 

data processing software, IAGA-IASPEI, Hanoi, Vietnam, 

G5.03. 

Love, J. J., 2001. Vectorial statistics for geomagnetism, IAGAIASPEI, Hanoi, Vietnam, G1.12, 72. 

Love, J. J., 2001. Persistent asymmetry in the paleomagnetic 

vector field, AGU EOS, 82, F341. (Invited) 

Pankratz, L. W., Sauter, E. A., 2001. A new interactive PCbased data collection platform, IAGA-IASPEI, Hanoi, 

Vietnam, G5.01, 232. 

Quinn, J. M., 2001. Magnetic field models derived from 

Oersted and DMSP F-15 satellite data, IAGA-IASPEI, 

Hanoi, Vietnam, G5.04, 239. 

2000 

Love, J. J., 2000. Bi-Gaussian statistics for paleomagnetic 

vectors, AGU EOS, 81, F351. 

Quinn, J. M., 2000. Fluid flow at the core-mantle-boundary 

based on a special constraint derived from Ohm’s law, 

AGU EOS, 81, S176. 

Quinn, J. M., 2000. Geomagnetic surveys from the DMSP and 

NPOESS satellite series” during the decade 2000 to 2010 

and beyond, AGU EOS, 81, S182. 

38
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