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Page 208 B3. INTERAGENCY COMMUNICATION AND COORDINATION Appendix B3 was largely developed by the workshop participants and was coordinated by Christopher Harrison (Group Leader). Introduction Many federal agencies are involved in the collection and analysis of magnetic data. The needs of these agencies vary greatly, from purely scientific to operational needs, and there is also much overlap among their needs. Thus, it seems obvious that there should be a great deal of communication between the various government agencies, first to define their needs and to discover the areas of overlap, and second to prepare and carry out joint data collection or analysis programs. In some cases this communication has occurred and joint programs have been conducted. In other cases there has been little communication and the advantage of joint programs has not yet been realized by the relevant agencies. It is the objective of this report to describe the main missions of the government agencies in the field of geomagnetism. Various areas of possible communication and collaboration will be suggested. National Aeronautics and Space Administration (NASA) NASA has taken the primary initiative for satellite programs to measure the geomagnetic field. The most recent satellite to have done this was Magsat, 12 years ago. Despite considerable efforts during the intervening time, no subsequent geomagnetic satellite mission has been carried out. One current possibility is to collaborate with the European Space Agency (ESA) to launch ARISTOTELES by mid-1998.
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Page 209 ARISTOTELES is a joint magnetic field and gravity mission with a low-elevation phase to measure the crustal field and a high-elevation phase to measure the time-varying core field. The availability of gravity data from this mission would materially help the interpretation of upper-lithosphere magnetic anomalies. If the necessary collaboration with ESA cannot be arranged, the next best alternative would be for NASA to collaborate with the French and Italian space agencies to accomplish a similar mission. Another possibility is to collaborate with the French space agency to carry out the high-altitude Magnetic Field Explorer Magnolia mission. NASA also has a responsibility for scientific aircraft flights, and there is a possibility of carrying out magnetic field observations for aircraft in the future, under NASA's auspices. Should there be a negative decision on ARISTOTELES by ESA, NASA will consider one of these missions, or an alternative inexpensive magnetic field mission. The measurement of magnetic fields from satellites is driven by basic scientific needs; NASA has developed a competent group of scientists engaged in the study of the magnetic field of the Earth, from core field modelers to crustal anomaly experts. Major advances have been made in the ability to analyze noisy satellite data, to produce the most accurate magnetic field model possible. Spherical harmonic models of the geomagnetic field produced by NASA are major contributors to the International Geomagnetic Reference Field. NASA also supports a very strong program of research in the areas of magnetospheric and ionospheric physics. Major new science missions are under development under the International Solar Terrestrial Physics and the Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) programs. Smaller missions are also actively under development under the aegis of the Small Explorer (SMEX) program. A vigorous program of rocket and balloon flights directed at upper-atmosphere and ionospheric phenomena is also maintained. In addition, NASA supports a broad program of theory, data analysis, and modeling research in these fields. Advances have been made in the ability to deal with ionospheric and magnetospheric fields and to deal with the temporally varying portion of the core field. The availability of a superior magnetic field model for
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Page 210 1980, mainly generated by Magsat data, has rejuvenated the study of the magnetic properties of the core and of the core-surface motions thought to be responsible for the secular variation of the Earth's magnetic field. Interest in the crustal component of the field has encouraged study of the rock magnetic properties of candidate rock types thought to be responsible for the long-wavelength magnetic anomalies recorded at satellite altitude. U.S. Geological Survey (USGS) The USGS is part of the U.S. Department of the Interior. One of the major tasks of the USGS in the field of geomagnetism is to operate the geomagnetic observatories within the United States and its territories. At the moment, there are 13 observatories in operation. The USGS has been a major force in the creation of INTERMAGNET, an international program to set up state-of-the-art geomagnetic observatories with the ability to transmit digital data in real time to the data centers. CD-ROMs of 1-minute observatory data are available from USGS. Geomagnetic observatories produce important data sets for the generation of geomagnetic reference fields, and USGS has a task to produce such models, which are candidate models for the IGRF. The INTERMAGNET program will eventually expand to about 70 observatories. The USGS also produces geomagnetic charts of the United States and the world every 5 years. There is also a service to provide model values of the geomagnetic elements by means of an on-line, dial-in service. Because of the major role that USGS plays in understanding the crustal geology of the United States, there is considerable emphasis on the collection and analysis of crustal geomagnetic field anomalies both on land and over areas of the exclusive economic zone. The USGS conducts low-altitude aeromagnetic studies for mineral and energy assessment, earthquake, and volcanic hazard studies, and a variety of other USGS missions. Paleomagnetic and rock magnetic laboratories conduct geological and tectonic investigations and participate in the interpretation of magnetic anomalies. Despite the fact that USGS, NOAA, and the U.S. Navy have responsibilities for the collection of geomagnetic field anomaly
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Page 211 data, there is little formal communication among these agencies. There is, however, much informal communication. Because of the need to remove the diurnal variation of the magnetic field from surveys to give an accurate value of the internal field, some effort is spent by USGS to produce more accurate and predictive models for the Sq variation. USGS interest in crustal magnetic field anomalies resulted in cosponsorship of Magsat with NASA. There is still interest in USGS in obtaining a more detailed crustal anomaly data base by flying a satellite in a lower orbit than Magsat. The USGS can support and coordinate multiagency acquisition of new aeromagnetic data in the United States by use of improved data-merging techniques and by use of USGS geophysical aircraft. These aircraft can fly long baselines to tie more localized surveys together and can also perform low-altitude surveys in areas related to missions of USGS and other federal agencies. Funding for the acquisition of a second-generation national magnetic map by USGS is problematic at this time because of severe budgetary limitations and because of the broad scope of this type of project. This effort will require participation from a wide base of the geomagnetic community, coordinated by USGS, but involving the support, cooperation, and participation of other federal agencies, state governments, industry, and academia. The USGS also carries out MT and MV studies for resource assessment. This work is funded in part by DOE because of the geothermal resource implications of the research, and by EPA. Some work is done by USGS to calculate upper- and lower-mantle conductivity by using observatory data. The USGS does not fund a great deal of work extramurally in geomagnetism, partly because of budgetary cutbacks in recent years. There is considerable informal collaboration with university scientists. Some forms of collaboration, such as the employment of students, is sometimes made difficult by bureaucratic problems. This is certainly an area where practices could be improved, with benefits both to USGS and to the university community.
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Page 212 National Oceanic and Atmospheric Administration (NOAA) NOAA is part of the U.S. Department of Commerce. It currently operates two series of environmental satellites in geostationary and low-polar orbit. One important NOAA mission is to monitor geomagnetic field activity. Jointly with the Air Force Air Weather Service, NOAA operates the Space Environment Services Center, which is staffed 24 hours a day. SESC monitors the level of activity of the Earth's magnetic field and informs other government agencies, educational institutions, and industrial centers when the amplitude of fluctuations exceeds a preset threshold. High magnetic activity sometimes causes disruption of important systems, such as power grids and communication networks. Some of the data used in this monitoring activity comes from NOAA-managed magnetometers of the Geostationary Operational Environmental Satellites (GOES). NOAA also issues predictions of geomagnetic activity for similar uses. Because the variations of the magnetic field which are of importance in these predictions and warnings are often caused by solar activity, NOAA scientists also conduct research in solar-terrestrial relationships. NOAA's weather satellites sometimes malfunction due to magnetic storms; thus, a greater knowledge of these phenomena is important for this agency. NOAA also has a responsibility for the production of nautical charts of coastal areas, and requires magnetic field information to indicate the magnetic variation (declination) and its change on these charts. The U.S. Navy (see below) has a similar responsibility for charts of oceanic areas. Aeronautical charts are also NOAA's responsibility. NOAA still has a small deep-sea geophysics program and collects towed magnetometer data on these geophysical cruises. Because of its fisheries responsibilities, NOAA is interested in the magnetic field and its relationship to the navigation and stranding of marine mammals. NOAA has a major responsibility to maintain data centers related to geophysics and the environment. These centers are responsible for
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Page 213 distributing information from numerous data bases. Included in these data bases are marine magnetic fields recorded by research vessels, information about continental magnetic anomalies, information from satellites such as Magsat and the POGO satellites, aircraft data, and data from geomagnetic observatories. NOAA is also responsible for distribution of magnetic field models, such as the coefficients of the International Geomagnetic Reference Field, and distribution of information about magnetospheric models. Most magnetic field information that is used to develop the IGRF models can be found in the NOAA Data Centers. One problem is that data digitization has not kept pace with data acquisition. A solution to this problem needs to be developed. U.S. Department of Defense (DOD) Defense Mapping Agency (DMA) The DMA has major responsibilities in geomagnetism, including management of the DOD Geomagnetic Data Library. This library contains all data collected by Project Magnet, both classified and unclassified. In association with the U.S. Navy, DMA produces the DOD World Magnetic Models, which are candidate models for the IGRF. These models are developed in collaboration with the British Geological Survey. Operational requirements from the Service Departments of DOD require data to be collected for navigation, directional sensors, magnetic anomaly detection for antisubmarine warfare, magnetic degaussing, targeting, and mine warfare. Most of these requirements can be satisfied by directional capabilities with 1° accuracy. DMA products include a world magnetic field model, compass roses on maps and charts, world geophysical data charts, and magnetic anomaly detection charts (classified). DMA also responds to special requests from DOD users.
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Page 214 Department of the Navy The U.S. Navy runs some major geomagnetic programs. Of these, one of the most important is Project Magnet. This aircraft program collects magnetic field data worldwide using advanced scalar and vector magnetometers. These data are used in the DOD World Magnetic Model. The vector data are especially useful in equatorial areas, where the POGS data (see below) being only scalar, will lead to large Backus effect problems in development of geomagnetic models. The Polar Orbiting Geomagnetic Satellite is another very important program. This system is currently capable of generating scalar data only, and may suffer from unknown drifts in the fluxgate magnetometers. Starting in 1994, the magnetic field instruments will be placed on the Block 5 DMSP satellites. These are operational meteorological satellites. Although the satellites are oriented in space, the boom on which the magnetometer sensors will be placed will have no attitude transfer system; thus, these satellites will still effectively be only scalar instruments. In 2005, it is planned to mount fully oriented magnetometers on the Block 6 DMSP satellites. Department of the Air Force The Air Force mission requires magnetic field measurements as a component of its effort to monitor “space weather.” Thus, the primary interest is in the magnetic disturbance vector measured on satellites at the first Lagrangian point (L-1), at geosynchronous orbit, in low-Earth orbit, and as recorded at ground stations. The Air Force has a secondary interest in the Earth's main field only as a baseline from which to measure magnetic disturbances.
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Page 215 National Science Foundation (NSF) The National Science Foundation funds many programs in geomagnetism—mainly through the Divisions of Earth Sciences, Ocean Sciences, Atmospheric Sciences, and Polar Programs. There is thus support for a range of studies in ionospheric and magnetospheric physics. Theoretical work on core dynamo problems and experimental work on paleomagnetic constraints are major relevant programs. In addition, there is much work on tectonic problems and, although there is not much support for the analysis of lithospheric magnetic anomalies except in oceanic areas, the overall crustal program within NSF provides important constraints for lithospheric models of magnetic anomalies. There is also some support for electromagnetic studies, both of deep Earth and crustal conductivity. Of particular relevance to the geomagnetic initiative is a proposed new NSF program, Cooperative Studies of the Earth's Deep Interior (CSEDI), which will support research associated with the international SEDI program. The NSF Ridge Inter-Disciplinary Global Experiments (RIDGE) program has considerable involvement from scientists in NOAA (through the Vents program) and USGS. Interaction between NSF and other agencies occurs in ad hoc arrangements, and there seems to be little difficulty in setting up formal or informal cooperative agreements with other federal agencies, as needed. Recommendations The current efforts to commence a satellite mission (ARISTOTELES) with the European Space Agency should continue. If this mission is not initiated, then other missions should be pursued—such as MFE-Magnolia. The later Block 5 DMSP satellites should be upgraded by the addition of a scalar magnetometer at the end of the 5-meter boom, to provide absolute control on the drift of the vector instruments.
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Page 216 The Block 6 DMSP satellites should be upgraded to give absolute vector measurements of the Earth's magnetic field to an accuracy of 4 nanoteslas per coordinate. The attitude determination should be accurate to 15 arc seconds. Discussions should take place between NOAA and NASA about the possibility of placing magnetometers on the NOAA polar-orbiting satellites. Educational concerns of geomagnetism should be pursued. Educational concerns might be pursued in the following ways. Government agencies are encouraged to seek student involvement in their projects whenever possible. This could be accomplished in large part by employment of students during the summer at government facilities. In certain situations, students from nearby universities could work at a government facility during the school year. Appropriate agencies could fund student stipends and expenses through university grants or contracts. Since the number of women and minorities entering professional science careers is still small, special encouragement should be given to these groups. This can be most effectively done at the undergraduate level. Some agencies have student programs at present; they are encouraged to study these programs to ensure that they are effective and easy to implement. (Some programs are known to suffer from rules that are too rigid for effective student involvement.) Another educational program might entail visits of government scientists to universities to present scientific talks. This program should be restarted by the National Science Foundation. It affords the opportunity to inform and educate students who are not science majors about interesting government research. Programs that inform the nonscientist about major scientific experiments and results are considered extremely important in generating a satisfactory research climate within the country. Some of the classified data collected by the U.S. Navy from surface ships would be of great use to the geomagnetic communi
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Page 217 ty. A request should be made to the Navy to release as much data as possible to the NOAA National Geodetic Survey for the appropriate filtering, binning, or culling under classified protocols. Information of this type even if culled, averaged, or otherwise filtered over a spatial scale of 100 km would be extremely useful to regional and main field modelers. The data derived in this way could be used to improve the Navy's field model. Of greater value would be data averaged over considerably shorter spatial scales (for example, over a few kilometers). Such data could be used in lithospheric magnetic modeling studies or in determining the age of the seafloor from seafloor spreading anomalies. Basic geological knowledge of this sort would be of great value to the scientific community, especially in areas sparsely covered by unclassified data. Declassifying its data would also be of value to the Navy itself, because the knowledge of the crustal age is of predictive use for the determination of sediment coverage, an important aspect of the acoustic behavior of the ocean floor. These filtered data can then be released to the NGDC with appropriate controls on dissemination, as prescribed by the Navy. Steps should be taken to implement a satellite program to monitor the L-1 Lagrangian point, with 24-hour real time transmission of data to the ground. The effective warning of geomagnetic storms would have immense monetary benefits to the country, and the data obtained would help improve the understanding of the external magnetic field of Earth and so provide a better internal field model. These steps should be taken jointly by NASA, NOAA, DOE, and DOD. ISTP satellites in geostationary orbit should also be used to gather data to study the solar wind. Federal agencies (particularly NOAA and NASA) should seek efficient and inexpensive ways of digitizing analog records from geomagnetic observatories. This might be done by subcontracting
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Page 218 to Russian agencies that have the capability of completing this work on time and at little expense. The INTERMAGNET program and others involving the setting up of geomagnetic observatories should be expanded. Collaboration between USGS and relevant organizations in other countries should be encouraged. This can be done by providing the state-of-the-art INTERMAGNET instrumentation to less developed countries, and setting up training programs to inform scientists and engineers from these countries how to achieve optimum performance from their instruments. In order to save on installation and data transmittal costs, new geomagnetic observatories should be collocated with other geophysical observatories, such as the Fiducial Laboratories for an International Natural (FLINN) network, or the IRIS network. Coordination of these geophysical observatories should involve NSF, NOAA, USGS, NASA, DOD, and other relevant federal agencies. The antarctic geomagnetic observatories financed by the NSF Division of Polar Programs should be converted into absolute instruments with help from the USGS. A national effort should be implemented to acquire a new airborne and shipborne magnetic map and digital data base of the United States and its EEZ. Such an effort would logically be coordinated by USGS, but it should involve the support, cooperation, and participation of other federal agencies, state governments, industry, and academia. A data coordination arrangement should be set up among those federal agencies collecting or holding significant geomagnetic data sets. The relevant representatives should meet often enough to ensure effective communication and collaboration.
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