Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
4 Current Space Weather Services Infrastructure The goal for the workshopâs third session was to identify the space weather products (data, services, and forecasts) that are available, the organizations that provide these products, and the means by which these products are made available to a wide variety of customers. To begin, five panel members, representing various government sectors of the U.S. and European space weather community, were invited to provide their perspectives. The panel included O. Chris St. Cyr and Charles Holmes, both from NASA; William Murtagh of the Space Weather Prediction Center (SWPC) of the National Oceanic and Atmospheric Administration (NOAA); Major Herbert Keyser from the U.S. Air Force (USAF) Director of Weatherâs office; and Michael Hapgood of the Science and Technology Facilities Councilâs Rutherford Appleton Laboratory. These speakers were asked to provide a review of current space weather resources and services along with their understanding of which elements are most important and which may be missing or require substantial effort to meet customersâ expressed needs and expectations. To aid in the preparation for the workshop, each of the speakers was asked to answer the following questions: 1. What current data sources and services infrastructure are used or provided by your organization(s)? 2. What space weather services (including data) are provided? Identify which are situational awareness (now- casting) services and which are forecasting services. 3. What models and tools do you use to provide your services? Identify which are physics based, expert system based, neural network based, empirically based, and so on. 4. Who are your primary customers? 5. What is the latency of the services relative to real time? For the forecasting services, what is the prediction window? Two additional questions were specifically addressed to the NASA representatives: 6. Will NASA provide its own space weather monitoring for the exploration missions or will it also rely on support from others such as NOAA? 7. Does NASA plan to help with the transfer to operations of the results from the theory and modeling pro- grams it supports? 35
36 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS These questions, and the answers and comments presented in this chapter, helped to clarify the existing status of space weather resources, how they can be accessed, and what is needed to maintain them. At times, the questions and comments from the audience extended somewhat beyond the sessionâs main purpose to address, for example, the issue of how new forecasters can be attracted and educated to maintain the staffing of the infrastructure. Space weather data, infrastructure, and services provided for space weather situational awareness and forecasting NASA and NOAA Roles Space weather data are currently provided by assets controlled by government organizations in both the civilian (primarily NASA and NOAA) and the defense sectors (primarily the USAF). NASA relies on a fleet of spacecraft in Earth orbit as well as in orbits around the Sun at 1 AU. See Figure 4.1. Although the NASA mis- sions are all primarily for scientific research, they provide much of the space weather data used by both civilian and military customers. NASA space missions track solar disturbances from their sources on the Sun, follow their propagation through the heliosphere (i.e., interplanetary space), and measure their impacts at Earth. The satellites use a combination of remote sensing observations of the Sun and direct in situ measurements of the solar wind. FIGURE 4.1â Missions collecting heliophysics data. SOURCE: O.C. St. Cyr, NASA-GSFC, âCurrent Space Weather Services,â 4.1 StCyr.eps presentation to the space weather workshop, May 22, 2008. bitmap
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 37 The Earth-orbiting spacecraft take critical measurements of space weather effects in Earthâs magnetosphere and ionosphere. In addition, numerous ground-based observatories provide data for characterizing space weather conditions and effects. NASAâs role in space weather was discussed by St. Cyr (NASA/Goddard) and Holmes (NASA Headquarters). St. Cyr noted that although NASA missions are driven by scientific priorities, these missions can and do supply substantial and critical space weather information. However, NASA does not provide space weather situational awareness (SA)1 and forecasting services. NASA does have strong theory and modeling programs that are attempt- ing to produce physics-based models that can be used in the development of forecasting and SA tools. As such, at NASA, heliophysics is the science behind space weather. St. Cyr emphasized NASAâs research-to-operations challenge that foresees the adoption of a distributed sensor network coupled to future large-scale data-assimila- tion space environment models. He pointed to NASAâs support for the development of space-based sensors that make many of the measurements needed for space weather applications and noted that many are developed for the first time at NASA and then transitioned to operations with other agencies. In many cases, the data returned from NASAâs near-Earth and interplanetary missions, especially ACE and SOHO (in cooperation with the European Space Agency) are used for space weather analysis. Providing a data beacon on ACE so that its summary data could be made available to organizations, like NOAA SWPC, created the ability to generate new forecasting and SA services. Holmes noted that NASA has deployed beacons on the currently operating Solar-Terrestrial Relations Observatory (STEREO) spacecraft. NASA would like to provide beacons, wherever feasible, on its future satellite missions such as the Radiation Belt Storm Probe (RBSP) and the Magnetosphere Multi-Scale (MMS) mission. He also noted that NASA, which operates a large fleet of spacecraft affected by space weather, is developing require- ments in an ongoing study that is examining the current status of SA services and forecasting and is looking at how these activities can be improved using todayâs knowledge. One of the primary questions the study will address is what is needed from the space weather perspective if NASA sends humans back to the Moon and to Mars. Holmes described the linkages between the existing Heliophysics Great Observatory, the data it provides, and the science being developed by using these data. This science provides the necessary basis for space weather SA and forecasting. He pointed out a relatively recent development from SOHO that improves the ability to predict solar radiation storms. A new data analysis technique allows electron particle flux measurements from the COSTEP sensor to be used to predict the arrival times of MeV protons from solar events. This science result has now been turned into a near-real-time capability to forecast the arrival of solar protons in near-Earth space where these protons can harm satellites and humans. He also emphasized that in time, as the STEREO Behind spacecraft gets farther away from the Earth-Sun line, as shown in Figure 4.2, it will provide a view of solar disk features about a week or more in advance of when they will be visible from Earth. Combining the STEREO Ahead and Behind views with the SOHO view (on the Earth-Sun line) currently provides NOAA and Air Force Weather Agency (AFWA) forecasters with a nearly 360Â° view of the solar surface. These data can be used to forecast when active regions on the Sun will be in a position to affect Earth, should they erupt. He then noted that when launched the Solar Dynamics Observatory (SDO) will provide continuous space weather data with only a 15-minute delay. Thus data from solar eruptions and their evolution will be available to forecasting models in near-real time. The SDO project has been working with the forecast community to identify the useful data content, and to show how the SDO data can be accessed. As mentioned above, NASA spacecraft provide sources of raw data that are used directly by customers to access space weather SA. However, these data are also used by the NOAA National Weather Service (NWS) SWPC, the USAF, and European organizations to produce more refined, long-term forecasting products. The NOAA SWPC has primary responsibility for the civilian communitiesâ operational space weather prod- ucts and forecasting services. Murtagh noted that NOAA SWPC provides multiple watches, warnings, alerts, and summaries to inform the user communities. These notices are often automatic responses to expected disturbances that are forecast based on past experience and current data. These may be general, such as expectations that there may be a solar event based on structures observed on the solar disk. In such cases, the notice identifies which data generated the concern and provides some limited information on the basis for the forecast. Watches are used for making long-lead predictions of geomagnetic activity. Warnings are used to raise customersâ level of alert- ness based on an expectation that a space weather event is imminent. Alerts indicate that the observed conditions,
38 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS 4 yr. 3 yr. Ahead @ +22Â°/year 2 yr. 1 yr. Sun Sun Earth Ahead 1yr. Earth Behind @ -22Â°/year Behind 2yr. 4 yr. 3 yr. FIGURE 4.2â STEREO orbits. Left: Heliocentric inertial coordinates (ecliptic plane projection). Right: Geocentric solar eclip- 4.2 Holmes.eps tic coordinates, fixed Earth-Sun line (ecliptic plane projection). SOURCE: Charles P. Holmes, NASA Heliophysics Division, Science Mission Directorate, âNASAâs Heliophysics Great with vector type 2 bitmaps Observatory,â presentation to the space weather workshop, May 22, 2008. highlighted by the warnings, have crossed a preset threshold or that a space weather event has already started. Finally, summaries are issued to keep customers informed about the progress of the event and to characterize the event once it has ended. NOAA SWPC also provides 39 types of event-driven space weather operational productsï£§50 percent from GOES; 38 percent from ground-based magnetometer measurements; 7 percent from the USAFâs ground-based Solar Electro-Optical Network (SEON), which comprises the Solar Optical Observing Network (SOON) and the Radio Solar Telescope Network (RSTN); and 2 percent from NASAâs ACE spacecraft, as shown in Figure 4.3. NOAA requires that primary data sources be real time and continuous, and that they have redundancy. This requirement is not met for most of the NASA research missions with the exception of ACE. ACE provides data to NOAA from its position at the L1 Lagrangian point between the Sun and Earth. It is a primary data source for measurements of solar particles and magnetic fields. ACE provides a critical ~45-minute advance warning before a coronal mass ejection (CME) strikes Earth. The lack of a primary source of continuous coronagraphic observations like those provided by SOHO/LASCO puts NOAA in a vulnerable situation. Without a solar coronagraph it would be difficult to predict the properties and trajectories of CMEs that are responsible for large geomagnetic storms. NOAA forecasters use different scales and categories to characterize the magnitude and impact of space weather events in much the same way as meteorologists use intensity scales for hurricanes and tornados. For example, NOAA uses the R-scale, for radio blackouts based on solar x-ray flux from GOES, to characterize the level of interruption of communication in frequency ranges affected by the solar radio flux. NOAA also charac- terizes the magnitude of solar proton events and magnetic storms using the S-scale and the G-scale. These space weather scales are described in detail on NOAAâs website (see http://www.swpc.noaa.gov/Data/) and are sum- marized in Table 4.1. NOAAâs team of space weather forecasters uses more than 1,400 different types of data from NOAA, NASA, the USAF, and the USGS and other space- and ground-based platforms around the world, providing a variety of products and services for the worldwide space weather community via the NOAA website, by anonymous FTP server, and, for subscribers, as e-mail messages. The products are presented to the customer both graphically and textually. Twenty-four space weather alerts and 12 selected products are also available via the NOAA Weather Wire, the NWS direct broadcast system. The products and alerts available via Weather Wire are described on an
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 39 Primary Secondary GOES SOHO/LASCO POES SOHO/EIT Total Event-Driven Products = 39 Boulder/Fredericksburg STEREO magnetometers â¢ Boulder magnetometer 15 ACE Ground- and space- â¢ GOES 20 based observatories â¢ SEON 03 (research focus) â¢ ACE 01 SEON (SOON and Ground-based RSTN) magnetometers Neutron monitors and riometers FIGURE 4.3â Space weather data sources. Primary 4.3 sources, which are required for driving operational products, must be data Murtagh.eps real-time and continuous. Secondary data sources are used to enhance products. SOURCE: William Murtagh, NOAA Space Weather Prediction Center, âCurrent Space Weather Services Infrastructure,â presentation to the space weather workshop, May 22, 2008. associated website (see http://www.swpc.noaa.gov/wwire.html). In addition to giving a view of the current situ- ation, or now-casting, NOAAâs products also provide near-term (hours to days) and long-term (months to years) forecasts and trends. An example of the latter is the forecast that attempts to project the duration of space weather events and, for solar events, provide some guidance relative to delayed effects like magnetic storms that are often generated by the resultant disturbed and enhanced solar wind. Another example is the use of GOES measurements to make 24- to 48-hour advance predictions of trapped radiation fluxes at geosynchronous orbits. Department of Defense Efforts The Department of Defense (DOD) is both a user and a supplier of space weather information. Herbert Keyser noted that presidential policy makes the DOD responsible for protecting U.S. space-based activities. This makes it of utmost importance for the DOD to elevate the capabilities of its space weather systems and improve the quality of its products. Within DOD, the USAF is the lead organization for space weather activities. The Air Force uses space-based observations from satellites operated by the Defense Meteorological Satellites Program (DMSP), the Defense Support Program (DSP), and the Communications/Navigation Outage Forecast System (C/NOFS), to name a few. The Global Positioning System (GPS) network is used to provide data on the total electron content (TEC) of the ionosphere. Ground-based measurements provided by the USAF currently include those made by the Solar Optical Observing Network (SOON), Radio Solar Telescope Network (RSTN), and Digital Ionospheric Sounding System (DISS). In the near future, the Improved SOON (ISOON) will replace the SOON, and the Next Generation Ionosonde (NEXION) sensors will replace the DISS. Most of these facilities operate 24 hours per day or, in the case of the solar observatories, from sunrise to sunset. To meet its DOD customersâ needs for space weather data and products, the Air Force combines NOAAâs data with data from its own sources. For example, the NOAA data products are used by the specialists at AFWA to provide assessments of the impacts of space weather on many different DOD âmissions,â a mission being a task that needs to be performed to support DOD activities. Keyser described five example mission areas that are affected by space weather: geolocation, communications, satellite operations, space tracking, and navigation. To perform these missions with high reliability requires knowledge of the ionospheric electron content, ionospheric disturbance levels, energetic particles, radiation disturbances, and magnetic disturbances, respectively. Ionospheric
40 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS TABLE 4.1 NOAA Space Weather Scales Category Effect Physical Average Frequency measure (1 cycle = 11 years) Scale Descriptor Duration of event will influence severity of effects Kp values* Number of storm events Geomagnetic Storms determined every 3 hours when Kp level was met; (number of storm days) Power systems: widespread voltage control problems and protective system problems can occur, some grid Kp=9 4 per cycle systems may experience complete collapse or blackouts. Transformers may experience damage. (4 days per cycle) Spacecraft operations: may experience extensive surface charging, problems with orientation, uplink/downlink and tracking satellites. G5 Extreme Other systems: pipeline currents can reach hundreds of amps, HF (high frequency) radio propagation may be impossible in many areas for one to two days, satellite navigation may be degraded for days, low-frequency radio navigation can be out for hours, and aurora has been seen as low as Florida and southern Texas (typically 40Â° geomagnetic lat.)**. Power systems: possible widespread voltage control problems and some protective systems will mistakenly trip Kp=8, 100 per cycle out key assets from the grid. including a 9- (60 days per cycle) Spacecraft operations: may experience surface charging and tracking problems, corrections may be needed for G4 Severe orientation problems. Other systems: induced pipeline currents affect preventive measures, HF radio propagation sporadic, satellite navigation degraded for hours, low-frequency radio navigation disrupted, and aurora has been seen as low as Alabama and northern California (typically 45Â° geomagnetic lat.)**. Power systems: voltage corrections may be required, false alarms triggered on some protection devices. Kp=7 200 per cycle Spacecraft operations: surface charging may occur on satellite components, drag may increase on low-Earth-orbit (130 days per cycle) satellites, and corrections may be needed for orientation problems. G3 Strong Other systems: intermittent satellite navigation and low-frequency radio navigation problems may occur, HF radio may be intermittent, and aurora has been seen as low as Illinois and Oregon (typically 50Â° geomagnetic lat.)**. Power systems: high-latitude power systems may experience voltage alarms, long-duration storms may cause Kp=6 600 per cycle transformer damage. (360 days per cycle) Spacecraft operations: corrective actions to orientation may be required by ground control; possible changes in G2 Moderate drag affect orbit predictions. Other systems: HF radio propagation can fade at higher latitudes, and aurora has been seen as low as New York and Idaho (typically 55Â° geomagnetic lat.)**. Power systems: weak power grid fluctuations can occur. Kp=5 1700 per cycle Spacecraft operations: minor impact on satellite operations possible. (900 days per cycle) G1 Minor Other systems: migratory animals are affected at this and higher levels; aurora is commonly visible at high latitudes (northern Michigan and Maine)**. * Based on this measure, but other physical measures are also considered. ** For specific locations around the globe, use geomagnetic latitude to determine likely sightings (see www.sec.noaa.gov/Aurora) Flux level of > Number of events when Solar Radiation Storms 10 MeV particles (ions)* flux level was met** 5 Biological: unavoidable high radiation hazard to astronauts on EVA (extra-vehicular activity); passengers and 10 Fewer than 1 per cycle crew in high-flying aircraft at high latitudes may be exposed to radiation risk. *** Satellite operations: satellites may be rendered useless, memory impacts can cause loss of control, may cause S5 Extreme serious noise in image data, star-trackers may be unable to locate sources; permanent damage to solar panels possible. Other systems: complete blackout of HF (high frequency) communications possible through the polar regions, and position errors make navigation operations extremely difficult. Biological: unavoidable radiation hazard to astronauts on EVA; passengers and crew in high-flying aircraft at 104 3 per cycle high latitudes may be exposed to radiation risk.*** Satellite operations: may experience memory device problems and noise on imaging systems; star-tracker S4 Severe problems may cause orientation problems, and solar panel efficiency can be degraded. Other systems: blackout of HF radio communications through the polar regions and increased navigation errors over several days are likely. Biological: radiation hazard avoidance recommended for astronauts on EVA; passengers and crew in high-flying 103 10 per cycle aircraft at high latitudes may be exposed to radiation risk.*** S3 Strong Satellite operations: single-event upsets, noise in imaging systems, and slight reduction of efficiency in solar panel are likely. Other systems: degraded HF radio propagation through the polar regions and navigation position errors likely. Biological: passengers and crew in high-flying aircraft at high latitudes may be exposed to elevated radiation 102 25 per cycle risk.*** S2 Moderate Satellite operations: infrequent single-event upsets possible. Other systems: effects on HF propagation through the polar regions, and navigation at polar cap locations possibly affected. Biological: none. 10 50 per cycle S1 Minor Satellite operations: none. Other systems: minor impacts on HF radio in the polar regions. -1 -1 -2 * Flux levels are 5 minute averages. Flux in particlesÂ·s Â·ster Â·cm Based on this measure, but other physical measures are also considered. ** These events can last more than one day. *** High energy particle measurements (>100 MeV) are a better indicator of radiation risk to passenger and crews. Pregnant women are particularly susceptible. GOES X-ray Number of events when Radio Blackouts peak brightness by class and by flux level was met; (number of storm days) flux* HF Radio: Complete HF (high frequency**) radio blackout on the entire sunlit side of the Earth lasting for a X20 Fewer than 1 per cycle number of hours. This results in no HF radio contact with mariners and en route aviators in this sector. (2x10-3) R5 Extreme Navigation: Low-frequency navigation signals used by maritime and general aviation systems experience outages on the sunlit side of the Earth for many hours, causing loss in positioning. Increased satellite navigation errors in positioning for several hours on the sunlit side of Earth, which may spread into the night side. HF Radio: HF radio communication blackout on most of the sunlit side of Earth for one to two hours. HF radio X10 8 per cycle contact lost during this time. (10-3) (8 days per cycle) R4 Severe Navigation: Outages of low-frequency navigation signals cause increased error in positioning for one to two hours. Minor disruptions of satellite navigation possible on the sunlit side of Earth. HF Radio: Wide area blackout of HF radio communication, loss of radio contact for about an hour on sunlit side X1 175 per cycle R3 Strong of Earth. (10-4) (140 days per cycle) Navigation: Low-frequency navigation signals degraded for about an hour. HF Radio: Limited blackout of HF radio communication on sunlit side, loss of radio contact for tens of minutes. M5 350 per cycle R2 Moderate Navigation: Degradation of low-frequency navigation signals for tens of minutes. (5x10-5) (300 days per cycle) HF Radio: Weak or minor degradation of HF radio communication on sunlit side, occasional loss of radio M1 2000 per cycle R1 Minor contact. (10-5) (950 days per cycle) Navigation: Low-frequency navigation signals degraded for brief intervals. * Flux, measured in the 0.1-0.8 nm range, in WÂ·m-2. Based on this measure, but other physical measures are also considered. ** Other frequencies may also be affected by these conditions. URL: www.sec.noaa.gov/NOAAScales March 1, 2005 SOURCE: NOAA Space Weather Prediction Center; see http://www.swpc.noaa.gov/NOAAscales/. 4.1 Table 4.1 NOAAscales.eps
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 41 disturbances affect both communications (because of signal fade, degradation, and loss) and navigation (GPS signal degradation) in much the same way. Figure 4.4 summarizes the sources and types of space weather measurements that are needed to support each of those five military mission areas. Keyser indicated that, in addition to the missions and products shown in Figure 4.4, the overarching mission is to be able to distinguish between natural and man-made problems with U.S. technologies and systemsï£§i.e., are the âbad guys trying to prevent us from doing what we want to do.â The Air Force has to be able to attribute problems with systems to one of three categories: hardware and software failures, space weather effects, or any direct attacks on the systems. For example, was a solar radio burst or a thunderstorm the cause of a communica- tion problem, or was it caused by someone trying to deny the use of the communication band? He noted, âIf we can get to the point where we can plan and forecast space weather, . . . then we can mitigate these problems and possibly even exploit the advantage that we would have.â Given the Air Forceâs desire for products to enable the above missions, Keyser outlined current capability levels using a color-coded scale, as shown in Figure 4.4. In addition, he discussed different space weather effects in relation to impacts and indicated how AFWA forecasters generated their products, some of which include the following: ionospheric analyses, 24-hour forecasts, HF communications and geolocation error analyses, and auro- ral impacts on operations. It was immediately clear that much of the forecastersâ output was based on ârules of thumbâ and statistical relationships. It was also clear from Keyserâs presentation that many of the products were useful for now-casting, rather than forecasting, space weather events. To date, physical models are not routinely used, but AFWA is making progress on space environment models (see the section titled âSpace Weather Models and Toolsâ below). AFRL R&D work is progressing but needs more funding to transition these elements to opera- tions. For example, AFWA incorporated the GAIM (Global Assimilation of Ionospheric Measurements) model into its operations a year and a half ago. Such tools can make a great difference for the DOD. Keyser noted that Space-Based Example Mission Observing Forecasting Measurement Space Weather Parameter Supported Capability Capability (Threshold SSA) (Objective SSA) 1 DMSP/SES* Ionospheric Electrons (60%) 1, 2, 7 Geolocation 2 ACE/SOHO FO 3 GOES Ionospheric Disturbances (60%) 1, 2, 7 Communications 4 GPS Energetic Particles (90%) 1, 2, 3, 4, 5, 6, 7 Satellite Operations 5 DSP 6 NPOESS Radiation & Disturbances (75%) 1, 2, 3, 4, 5, 6, 7 Space Tracking 7 C/NOFS Ionospheric Disturbances (60%) 1, 2, 7 Navigation Good ( >75%) Moderate (50-75%) Marginal (25-50%) Little or None (0-25%) Ground-Based Example Mission Observing Forecasting Measurement Space Weather Parameter Supported Capability Capability (Threshold SSA) (Objective SSA) 1 SOON/ISOON 2 RSTN/RSTN II Ionospheric Electrons (60%) 1, 2, 3, 4, 5, 6 Geolocation 3 NEXION Ionospheric Disturbances (60%) 1, 2, 3, 4, 5, 6 Communications 4 TEC 5 SCINDA Energetic Particles (25%) 1, 2, 6 Satellite Operations 6 Geomag Radiation & Disturbances (40%) 1, 2, 3, 4, 5, 6 Space Tracking Ionospheric Disturbances (50%) 1, 2, 3, 4, 5, 6 Navigation *SES â Space Environment Sensors as payload on other satellites FIGURE 4.4â Space weather capability needs. SOURCE: Herbert Keyser, USAF, âSpace and Intel Weather Exploitation,â presentation to the space weather workshop, May 22,4.4 Keyser.eps 2008.
42 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS FY08 FY09 FY10 FY11 FY12 FY13 FY14 FY15 Spiral 2 IOC South Atlantic Physics-based COSMIC GAIM Full Physics SEEFS Anomaly Model Solar Wind Model SSUSI GAIM GUVI GAIM SSULI GAIM Integration Legacy programs HAF GAIM GAIM SWAFS (Space Wx Analysis & Forecast Sys) SWAFS JMSESS Delivery Plus-up. Radiation Dosage, Data-Driven Radiation Belt SEEFS (SSA Environmental Effects Fusion Sys) Begin Integration (SWAFS/JSpOC) Integration Complete Additional System Impact Models Additional System Impact Models FIGURE 4.5â Current and planned space weather tools andKeyser.eps 4.5 models. SOURCE: Herbert Keyser, USAF, âSpace and Intel Weather Exploitation,â presentation to the space weather workshop, May 22, 2008. the output of such tools could be used to tell an HF or special operations user that conditions are going to require a backup system, for example. The DOD is striving to increase the sampling of the space weather environment for the coming solar maximum (in 2011-2012) and beyond. NPOESS was supposed to do this by gradually replacing the role now performed by the DMSP satellites. However, the loss of all but one of its space weather sensors due to the Nunn-McCurdy Act means that there will be a gap in the space weather coverage starting at about 2016 if the loss of NPOESS sensors is not addressed. Keyser suggested that the best way to fix this situation is to invest more in partnerships with other agencies. He noted, for example, that âNSF has some great capabilities in their solar observatories. They have their science mission, and we donât want to impinge on that. However, at the same time we could both benefit from a little bit of investment on our part to get an operational use at the end of the day.â2 In addition, the Air Forceâs plan to enhance its capabilities to observe ionospheric weather includes leveraging âadditional ionosondes fielded by the National Science Foundation, NOAA, and international partners.â Finally, Keyser presented a schedule (Figure 4.5) showing the current status of USAF-developed tools and models, and their near-term products. Also identified were the tools and models that are expected to be implemented or available in the period from FY 2009 through FY 2015. European Programs Space weather, a global phenomenon that spans national boundaries, is a challenge best met by international cooperation. In this regard the committee sought to obtain information on the experiences of European colleagues. Hapgood presented a summary of the space weather programs in Europe, a mix of activities funded at national and European levels. The European-level activities are divided mainly between the European Union (EU) and the European Space Agency (ESA). The programs are a mix of research and operational activities from 25 countries in the EU and 17 countries involved in ESA. Hapgood described the space weather landscape in Europe as âcom- plicatedâ and âvery fragmented.â In addition, there is a large overlap of activities since many of the newest EU members are not a part of ESA. It should be noted that Canada, while not in Europe, is an associate member of ESA. In many ways, ESA is an analog to NASA with overtones of the National Science Foundation. ESA is funded by the member countries. When it comes to providing space weather services there is a cross-national perspective. In general the cross-national activities focus on the front-end services, i.e., the services that take data from sensors and deliver products, according to Hapgood. He provided a chart (reproduced as Figure 4.6) that showed many of the elements of the European space weather landscape. He noted that most of the communication occurs at the level of the boxes in Figure 4.6 marked DIAS, COST 296, and so on. (The COST designation is an acronym for Cooperation in Science and Technology.) The COST 724 (Space Weather Prediction Team) shown near the center of Figure 4.6 is being reformed, and Hapgood, the head of the SWWT (Space Weather Working Team) in the area of space weather prediction services, thinks that it will receive a new approval to go forward. The most important element in Figure 4.6, according to Hapgood, is the SWENET (Space Weather European Network), originally funded by ESA and still being provided some support by ESA as an R&D activity. SWENET
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 43 NATO? EDA Euro-SSA? EU ESA (enterprise, research) Space policy Feasibility eContent COST Studies DIAS COST 296 COST 724 SWWT SWENET SEENoTC Euro. digital upper radio + ionospheric Space weather Space Weather Space Environment & Network of services atmosphere server mitigation prediction Working Team Effects Euro SpW Week EUMETSAT + ECMWF FIGURE 4.6â Some elements of European space weather infrastructure. SOURCE: Michael Hapgood, STFC Rutherford 4.6 Hapgood.eps Appleton Laboratory, âCurrent Space Weather Services Infrastructure in Europe,â presentation to the space weather workshop, May 22, 2008. offers a way of federating a significant number of space weather services around Europe, between 25 and 30 at the moment. Its website (http://esaâspaceweather.net/swenet/ index.html) provides space weather data and data analysis with links to the NOAA SWPC website. SWENET services are organized into three categories: ground effects, ionospheric effects, and spacecraft effects. Under each category are multiple elements such as nowcasts, forecasts, and simulation outputs. Each is listed under a shorthand acronym that is often not self-explanatory. However, clicking on the elements takes the user to the site that developed the tool and identifies which institute hosts the content. The tools are generally developed by different research institutes within Europe. For example, the GIC (ground induced current) forecast was developed by the Swedish Institute of Space Physics (IRF) and is a prototype service that forecasts the rate of change of the local geomagnetic field, the ground electrical field, and GICs every 10 minutes. Since ESA is an R&D agency, the SWENET will ultimately reside outside ESA. There are also plans for a European space situational awareness (SAA) program being developed at ESA. That program could be a possible home for SWENET. The SAA activity will be federating existing assets, and so all the smaller national programs could be put into a larger context. A meeting is planned for November 2008 at which the min- istries of 25 to 30 nations will vote on the legal framework for SSA. European data sources for space weather measurements are fairly limited. Most of the space-based measure- ments are by-products of science research programs supported by ESA and the national space agencies. Two examples of instruments that can provide space weather data are (1) the Sun Watcher with AP-sensors and image processing (SWAP) on the Proba-2 mission and (2) the Heliospheric Imagers (HI) on the twin STEREO spacecraft. These instruments can provide warnings of flares and coronal mass ejections from the Sun. ESA is also interested in placing low-cost space radiation monitors on as many spacecraft as possible. In addition, there are many ground- based measurement systems located in Europe. These include magnetometers, neutron monitors, GPS receivers (for TEC and scintillation measurements), and ionosondes (for density and drift velocity measurements). A 2001
44 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS FIGURE 4.7â Space Weather Portal web page. SOURCE: Cost 724, ESA and BIRA-IASB. Reprinted with permission. 4.7 Hapgood.eps survey found ground-based space weather measurements provided by 20 countries, with France, Germany, Italy, and the U.K. providing the most measurements. Hapgood discussed in some detail a Web facility known as the European Space Weather Portal (http://www. spaceweather.eu/), the entry Web page to which is shown in Figure 4.7. He noted, âThis is a bottom-up initiative from the community to create a website that links into all kinds of space weather services across Europe.â It came out of the COST 724 initiative shown in Figure 4.6 and is currently in development. Examples of the types of models being developed are the exospheric solar wind model and a plasmapause location model. Both of these models provide proxies for observables that would be used by higher-level models that generate specific space weather products. Hapgoodâs analysis of the infrastructure for the European space weather community indicated that it has strengths in terms of the skills provided by the space science and engineering community, but also some major weaknesses, including the following: (1) the programs are fragmented, (2) there is limited awareness among the decision makers (who ultimately control the budgets), (3) many of the products are of poor quality, and (4) space weather is still seen as being a part of astronomy. Three threats were also identified: (1) the fragmented nature of the programs leads to piecemeal funding cuts, (2) there is competition with other areas of astronomy, and (3) many still view the space between the planets as empty and therefore harmless. Finally, several opportunities were suggested by Hapgood: (1) there is a strong case to be made for organizing in a global context, (2) better services can be provided through networking, and (3) the quality of space weather products should be improved. Space Weather Models and Tools Speakers for this workshop session were asked about which models and tools are in use by the space weather forecasting community and whether these are empirical or physics-based. Speakers from NOAA and the USAF stated that the majority of their models are empirically based. Such models are inexpensive to operate, are easy to use, and have shorter computer run-times compared to the more theoretical models. However, efforts are under way
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 45 by NOAA SWPC, AFWA, and other organizations to replace some of these models with physics-based models, which ultimately will be preferred because they represent a deeper understanding of cause-and-effect relationships. Physics-based models also have the potential to reduce the uncertainty in space weather forecasts. One program involved in this endeavor is operated by the Community Coordinated Modeling Center (CCMC), a multiagency partnership tasked with supporting the development, testing, and evaluation of advanced space weather models. The state-of-the-art CCMC models are used by both the science community and the space weather forecasting community, mainly for research purposes. One challenge is to identify the most useful models, simplify them, and make them more operationally friendly. NOAA uses its own models and tools to obtain additional lead time or to improve the accuracy of its space weather warnings and watches. Some examples of the space weather models used at SWPC are highlighted below.3 â¢ The D-region Absorption Prediction model predicts the impact of solar x-ray flares on the radio propagation characteristics of the ionosphere. This empirically based model is used extensively by the airlines in monitoring high frequency (HF) radio communications blackouts. â¢ The Storm-time Ionospheric Correction model provides information on departures from the normal F-region critical frequency in 20Â° latitude bands starting from +/â 20Â° geomagnetic latitude and increasing to the poles. The model provides a convenient tool for estimating the response of the ionosphere to geomagnetic activity. â¢ The U.S. Total Electron Content tool is a model for deriving the vertical and slant TEC over the continental United States in near-real time. This empirical tool is used to estimate the delays in GPS signals due to the changes in the electron content of the ionospheric path between the GPS satellite and the receiver. â¢ The Wang-Sheeley-Arge (WSA) model is used to predict the solar wind speed and the polarity of the interplanetary magnetic field (IMF) at Earth. These are two important quantities for determining the severity of geomagnetic disturbances caused by solar wind and CME events. The model uses data from solar magnetograms, the solar wind speed observed by the ACE spacecraft, and a potential field model to estimate the divergence of the solar magnetic field. Predictions of the solar wind speed and IMF polarity from 1 to 7 days in advance are routinely made with the WSA model. DOD space weather models are supported by NASA Headquarters, the USAF Weather Agency, and the Air Force Space Command (AFSPC). AFWA supports the Space Weather Analysis and Forecast System (SWAFS) that uses data and models from a variety of space weather sources. The current models used for SWAFS are empirical models, but ultimately SWAFS will use physics-based models for the global ionosphere, South Atlantic Anomaly, and the solar wind. The SWAFS models are currently being integrated into the AFSPCâs Space Situational Aware- ness Environmental Effects Fusion System (SEEFS). SEEFS provides more than near-real-time space weather conditions to operational users; it also provides system impact assessments so that operators can know when they have to switch to backup systems. Planned DOD investments in models, applications, graphics, data fusion, and decision aids will improve operational space weather support. In Europe, space weather services are being coordinated and made available through the community-wide European Space Weather Portal noted above (see Figure 4.7 and its associated website address). Most of the models appear to be empirically based models, with physics-based models being developed. Customers FOR Current Space Weather Services Workshop panel members indicated that their space weather customers are incredibly varied, ranging from those that want very specific and tailored products to those that are unsure about what they want or need. In all cases, speakers indicated that they are prepared to meet their customersâ needs or to learn what is missing and what can be done to better define the needs. In some cases the service providers have customers within their own organizationï£§for example, NASA needs space weather services to support its high-altitude aircraft and spaceflight missions. In many cases the necessary data services are being provided from other NASA missions. Ultimately, the workshop panelists from NASAâs Heliophysics Division felt that their primary customers were the
46 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS heliospheric science community. However, they also indicated that NASA missions from other directorates, such as those that support human and robotic explorers, those that provide launch activities, and those that support and operate NASAâs fleet of spacecraft, are also users of space weather data provided by the Heliospheric Division. As noted above, St. Cyr discussed the fact that within NASA a study is in progress to understand and define the requirements for all such mission support. Murtagh presented a list of SWPCâs primary customers. Figure 4.8 shows a range of impact areas with examples of specific customers from those areas, as well as types of actions that customers take in response to SWPC alerts and examples of the possible costs incurred by not taking such action. Figure 4.8 illustrates a need being fulfilled and the importance of the SWPCâs products to a very wide community. However, Murtagh also indicated (during the question-and-answer period) that more sophisticated services were being left up to commer- cial industry. Space weather data are gathered, reduced, and presented by NOAA SWPC along with some general products. However, it is up to private industry to develop the specialized products that target specific needs for specific customers. These products and services often use products that are generated by NOAA SWPC. However, NOAA SWPC does not compete with private industry in this activity. Hapgood provided examples of users for the three types of services available from the SWENET website discussed above. For the ionospheric services, he identified users from the GPS, HF radio systems (aviation, mili- tary, amateurs), and science communities. For geomagnetically induced currents and ground effects services, he identified the power grids of Scandinavia and Scotland, oil and mineral surveyors, and pipeline operators as users. EACH MONTH AT SWPC â¢ 400,000 Unique Customers â¢ 50,000,000 File Transfers â¢ 120 Countries Represented by Users â¢ 67,500,000 Web Hits â¢ 0.3 TBytes of Data Downloaded Impact Area Customer (examples) Action (examples) Cost (examples) Spacecraft â¢ Lockheed Martin â¢ Postpone launch â¢ Loss of spacecraft ~$500M (Individual systems to complete â¢ Orbital â¢ In orbit - Reboot systems â¢ Commercial loss exceeds $1B spacecraft failure; â¢ Boeing â¢ Turn off/safe instruments â¢ Worst case storm - $100B communications and radiation â¢ Space Systems Loral and/or spacecraft effects) â¢ NASA, DoD Electric Power â¢ U.S. Nuclear Regulatory Commission â¢ Adjust/reduce system load â¢ Estimated loss ~$400M from (Equipment damage to electrical â¢ N. America Electric Reliability Corp. â¢ Disconnect components unexpected geomagnetic storms grid failure and blackout â¢ Allegheny Power â¢ Postpone maintenance â¢ $3-6B loss in GDP (blackout) conditions) â¢ New York Power Authority Airlines (Communications) â¢ United Airlines â¢ Divert polar flights â¢ Cost ~ $100k per diverted flight (Loss of flight HF radio â¢ Lufthansa â¢ Change flight plans communications) â¢ $10-50k for re-routes â¢ Continental Airlines â¢ Change altitude (Radiation dose to crew and â¢ Korean Airlines â¢ Select alternate â¢ Health risks passengers) â¢ NavCanada (Air Traffic Control) communications Surveying and Navigation â¢ FAA-WAAS â¢ Postpone activities â¢ From $50k to $1M daily for single (Use of magnetic field or GPS â¢ Dept. of Transportation â¢ Redo survey company could be impacted) â¢ BP Alaska and Schlumberger â¢ Use backup systems FIGURE 4.8â Examples of customers and impact areas Murtagh.eps data. SOURCE: William Murtagh, NOAA Space 4.8 for space weather Weather Prediction Center, âCurrent Space Weather Services Infrastructure,â presentation to the space weather workshop, May 22, 2008.
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 47 Finally, for the spacecraft effects services, he identified satellite operators, like the European Satellite Operations Centre, as users. Keyser indicated that the entire DOD was his user and did not make distinctions between the different parts. In that sense, the DOD is its own customer and the AFWA is the primary source of its space weather services. He did note that the Air Force was given the responsibility for protecting all U.S. space assets. The primary DOD customers are organizations that provide or use geolocation, communications, navigation, space operations, and space object tracking services. Latency of services and forecast windows The workshop panel speakers did not explicitly answer the question about the latency of their services rela- tive to real time, but some information can be gained from the websites they supplied. Typically, data from NASA research missions are available in near-real time with delays from minutes to hours. Users can obtain these data directly from the mission project pages. NASA has provided beacon broadcast capability on some of its spacecraft (e.g., ACE, STEREO, and in the future SDO) to further decrease the time between the collection of data and their availability to users. NOAA SWPC also provides near-real-time space weather data and products from its website (http://www.swpc.noaa.gov/ Data/index.html#alerts). For example, the NOAA SWPC solar and geomagnetic indi- ces are updated frequently, with delays of 1 minute to a few hours, at worst. Data from the space weather sensors operated by the DOD and the model outputs produced from ingesting these data have latency periods similar to those of NOAA. Nearly all of the workshop speakers indicated that their data are available to users 24 hours per day on their websites. Users can also make requests to have data products and alerts sent via e-mail. Likewise, the prediction windows for the forecast services provided were not explicitly mentioned by all of the panel speakers. For the operational services (NOAA and DOD), assimilative models are in use to provide now-cast and forecast capabilities for space weather events and their impacts on operational systems. Using data from the ACE spacecraft, NOAA SWPC modelers can provide a warning time of approximately 1 hour for CME-related geomagnetic storms. These forecasts have a high level of confidence. NOAA provides daily forecasts of solar and geophysical activities for the next 24-72 hours in its Daily Space Weather Summary and Forecast reports. Less reliable long-term 7-day forecasts from NOAA are made in the Space Weather Advisory Outlooks that are issued each week. These are typically short descriptive statements indicating the likelihood of future space weather events. Three-day and 27-day advance forecasts of quantitative solar and geophysical indices (e.g., x-ray flare probability, 10.7-cm radio flux, Ap and Kp) are also produced by NOAA SWPC. The 3-day forecasts are issued daily, and the 27-day forecasts are issued weekly. The DOD uses similar forecasts. An important point emphasized by Keyser is that the military is interested not so much in forecasting the space weather environment as in forecasting and mitigating space weather impacts on their operational systems. During the question-and-answer period, a speaker remarked that it would be immensely useful to be able to predict CME arrival times at Earth to within a couple of hours. Right now, using data from instruments like those on STEREO, predictions to within a half a day are not possible. This is a challenge for the physics-based models that describe the propagation of space weather disturbances from the Sun to Earth. Space weather monitoring for the NASA exploration missions As indicated in the combined presentations by St. Cyr and Holmes, NASA is currently conducting a self- assessment of the requirements for its human exploration mandate. St. Cyr noted that the Space Radiation Analysis Group at Johnson Space Center in Houston has the lead at NASA in the area of space weather impacts on human exploration. It was noted that the Houston group also works closely with NOAA SWPC. It was not clear which element of NASA had responsibility for monitoring space weather impacts affecting its purely robotic missions. However, it was stated that NASA would provide some of its own space weather investigations (such as through the Lunar Reconnaissance Orbiter) to satisfy both its science mission and its need for space weather monitoring.
48 SEVERE SPACE WEATHER EVENTSâUNDERSTANDING SOCIETAL AND ECONOMIC IMPACTS The NASA participants in the workshop noted that NASA would be working closely with NOAA SWPC and others on future exploration missions. Transfer of the Results of NASAâs Theory and Modeling Programs to Operations Both St. Cyr and Holmes indicated that NASA is currently working to transfer the results of its theory and modeling programs to agencies involved in operations. NASA participates in the multiagency CCMC, a partnership among NASA, NSF, NOAA, the Office of Naval Research, and several USAF organizations. Holmes summarized the activities of the CCMC, which he called the 15th mission of NASAâs Heliophysics Great Observatory, in his presentation. The CCMC is housed at Goddard and provides the opportunity for the developers of state-of-the-art physics models to load their models onto Goddardâs supercomputers and make the results of their runs available to the research and forecasting communities. It is, he believes, a great success story that shows what the com- munity has put together to support the modeling of space weather. A related topic that was mentioned was the transfer of space weather sensor technology initially developed for NASA science missions. Once the sensors have been proven and their data have been tested by the forecasting community, the sensors will be transitioned to the operational agencies. Questions and Discussion The question-and-answer session included a discussion of several issues related to space weather situational awareness and forecasting services. Some of the themes are presented in the examples given here. A two-part question asked, âWhat is the current status of radiation belt modeling and models . . . and who is responsible for the work in this area?â Joseph Fennell, a workshop attendee, noted that an ISO (International Organization for Standardization) activity to develop next-generation radiation models was being led by CNES in France, the Air Force Research Laboratory (AFRL), Los Alamos National Laboratory (LANL), the Aerospace Corporation, and others. Hapgood noted that one of the challenges faced in radiation belt modeling was obtaining good magnetic field models that underpin the radiation models. As in the panel presentations, there was much discussion of data that could be interpreted to get some idea of the space weather situation, but Daniel Baker noted that many users do not want data as much as they want results that they can readily apply. He asked the panel, âHow much are you thinking about not providing . . . close to raw data but [instead] much more integrated [products] that readily provide the answers that operators and users really need?â Murtagh answered that from the NOAA SWPC perspective there are a couple of things to consider. NOAA and the National Weather Service have a responsibility to provide data and a baseline product suite. But, he noted, SWPC has to be very careful that it does not cross into the area where commercial service providers take the opportunity to fine-tune some of the data and products provided by SPWC, an example being space weather services tailored for the power grid industry: even though SWPC can specify the space weather environment, an outside commercial service provider will provide information on the likelihood of a geomagnetically induced current. Keyser noted that for some time the DOD has been creating impact-based products for customers like the Space Command, adding that it is the impacts that the operator flying the satellite or reading the radar screens cares about. St. Cyr reiterated that NASAâs Living With a Star (LWS) program targets research and technologies and tries to bridge the âvalley of death,â the gap between research and operational tools. He noted that during the Space Weather Week meeting in Boulder (April 2008) a new model had been unveiled that had LWS support. The presentations made it clear that while there is much space weather data available, the number of tailored products that meet known user needs is limited but also is rapidly evolving. Another question that generated considerable interest dealt with whether a formal educational program existed for prospective space weather forecasters and budding service providers. Fennell noted that the Air Force tries to develop such people within its organization by offering extended education at Air Force expense. Keyser acknowledged that the Air Force production of space weather experts had declined. He remarked that he was probably one of youngest people in the room, noting at the same time that the audience, which included many of
CURRENT SPACE WEATHER SERVICES INFRASTRUCTURE 49 those interested in space weather, is a national resource that is quickly disappearing and that this, in his opinion, is an issue that needs to be addressed. Murtagh noted that NOAA SWPC is trying to address the problem and has had five to seven students per year in various summer programs. One audience member noted the large number of various types of programs discussed and wondered what they cost. He questioned what he felt was a lack of cooperation among the various agencies and also asked why the people using the services were not paying for them. He asked, âWhy does it seem like everything is so frayed?â Workshop participant Louis Lanzerotti pointed out that there is a U.S. National Space Weather Program and that several of the agencies involved in it were represented on the panel. Summary Space weather services in the United States are provided primarily by government organizations such as NASA, NOAAâs SWPC, and elements of the DOD. NASA has the largest number of civilian space satellites that provide the raw data used by other organizations in creating tailored products to meet customersâ needs. It is also the primary organization for providing the scientific research for understanding space weather phenomena. NOAA provides more refined space weather data, forecasts, and warning products that are most relevant to the public and industry. The U.S. Air Force is the lead agency designated with the responsibility for providing space weather assessments for the military. Its emphasis is on providing situational awareness (real-time conditions) of the space weather environment and assessments of impacts on military operations and systems. The space weather infrastructure cannot function without the continual stream of space weather data col- lected by various assets on the ground and in space. Although NASA currently provides much of the raw data from its research satellites, William Murtagh and Herbert Keyser said that they foresee potential gaps in space weather coverage because of inadequate plans for deploying new and dedicated systems. Other problems are caused by hardware development programs going over their budgets, such as NPOESS, which has led to cuts in future data collection capabilities. Several speakers mentioned the challenges of improving the cooperation among the various organizations that provide space weather services. In particular, Michael Hapgood highlighted the difficulties by describing the current European space weather infrastructure as âcomplicated and fragmented.â Essentially all speakers suggested that a strong case could be made for better networking with national and international partners. An example of a success story for cooperation is the multiagency CCMC, which has been tasked with transitioning research-based space weather models and making them more useful to the operational community. This is a major undertaking that is required to make the leap from now-casting to having the ability to predict severe storms days in advance. NOTES 1. Situational awareness involves the perception and understanding of current space events, threats, activities, and condi- tions, including natural environmental conditions and space systems status, capabilities, constraints, and use, and an ability to assess potential near-term outcomes. 2. Keyser referred specifically to the NSFâs Global Oscillation Network Group (GONG) and Synoptic Optical Long-term Investigation of the Sun (SOLIS) initiatives. 3. The complete list of space weather models used at SWPC can be found at http://www.swpc.noaa.gov/Data/index. html#models.