Becoming a Space Weather-Ready Nation

In the United States, scientific research in space weather is funded by several Government Agencies including the National Science Foundation (NSF) and the National Aeronautics and Space Agency (NASA). For commercial purposes, space weather forecast is made by the Space Weather Prediction Center (SWPC) of the National Oceanic and Atmospheric Administration (NOAA). Observations come from the network of groundbased observatories funded via various sources, as well as from the instruments on spacecraft. Numerical models used in forecast are developed in the framework of individual research projects. Later, the most promising models are selected for additional testing at SWPC. In order to increase the application of models in research and education, NASA in collaboration with other agencies created Community Coordinated Modeling Center (CCMC). In mid-1990, US scientific community presented compelling evidence for developing the National Program on Space Weather, and in 1995, such program has been formally created. In 2015, the National Council on Science and Technology issued two documents: the National Space Weather Strategy [1] and the Action Plan [2]. In the near future, these two documents will define the development of Space Weather research and forecasting activity in USA. Both documents emphasize the need for close international collaboration in area of space weather.

Over the past decades, missions at the L1 point have been providing solar wind and interplanetary magnetic field measurements that are necessary for forecasting space weather at Earth with high accuracy and a lead time of a few tens of minutes. Improving the lead time, while maintaining a relatively high level of accuracy, can be achieved with missions sunward of L1, so‐called sub‐L1 monitors. However, too much is unknown to plan for sub‐L1 monitors as operational missions: both the orbital requirements of such missions, and the achievable accuracy of forecasts based on their measurements have not been quantitatively defined. We review here some proposed mission concepts and explain the knowledge gaps related to coronal mass ejections (CMEs) that require a space weather research or science mission. We first show how STEREO‐A measurements in 2023 can be used as a proof of concept of the use of sub‐L1 monitor slightly off the Sun‐Earth line to forecast the Dst index. We then highlight that separations of are needed to ensure that CMEs measured by a sub‐L1 monitor impact Earth. Next, we show that measurements with angular separations of have negligible errors but separations of a few degrees can result in significant errors in lead time and in the forecasted magnetic field strength of CMEs. We also discuss how CME evolution over the last 0.05–0.2 au before impacting Earth is strongly under‐constrained and needs to be better understood before using measurements of sub‐L1 monitors for real‐time space weather forecasting.

The National Oceanic and Atmospheric Administration's Space Environment Center (SEC) is the principal U.S. governmental agency for providing space weather data, information, and forecasts across the user spectrum, including industry, other government entities, and the public. A major change in the reporting structure of the center is poised to occur later this year when Congress approves the fiscal year 2005 budget proposed by the Bush administration. The activities of the SEC, together with its proposed budget, will move from under NOAA's research budget and administration to that of the National Weather Service (NWS), which is also administered by NOAA. The weather service will receive augmented funding to accommodate the SEC as one of the service's National Centers for Environmental Prediction. The move, however, is more than a mere change in the wiring diagram for NOAA's administration. It would appear that NOAA is becoming more serious in recognizing and appreciating the essential responsibility that it, through the SEC, holds for supporting the nation's space environment needs. Indeed, the wording in the NWS portion of the NOAA budget strongly acknowledges this, requesting that Congress “allow the NWS to maintain the SEC's critical forecasts and products in support of the Nation's energy and telecommunications industries, NASA, and the [U.S. Department of Defense].” The SEC has long had, as a part of its mission, a research component. This activity allows the center to maintain an awareness of, and contribute to, advances in solar-terrestrial research, especially as applied to space weather. The NOAA budget for FY2005 suggests that this will continue as the SEC comes under the NWS umbrella, stating that the center “will continue to support the research framework necessary to ensure that new research findings are utilized.” We hope this will continue to be the case over the long term. In addition, the National Weather Service has a long history of interacting with private suppliers of weather information and providing value-added products. Such private-public interactions have sparked tensions in the past between the weather service and the atmospheric weather community, similar to concerns now beginning to be felt in the space weather community (see the related article on this topic by Genene Fisher in Space Weather). We hope the experiences encountered, and lessons learned, in the space and atmospheric weather communities will be beneficial to all parties as private-sector space weather services become stronger over time and as the SEC continues to grow in its service to all users. Louis J. Lanzerotti is Editor of Space Weather, a distinguished research professor at the New Jersey Institute of Technology, and a consulting physicist at Lucent Technologies’ Bell Laboratories.

Adverse space weather can pose high risks to mobile and wireless communications. Space weather forecasts can help manage the risks. This article presents three space weather forecast models that satisfy different user needs and operational constraints.

When we examine the impacts of space weather on society, do we really understand the risks? Can past experiences reliably predict what will happen in the future? As the complexity of technology increases, there is the potential for it to become more fragile, allowing for a single point of failure to bring down the entire system. Take the Global Positioning System (GPS) as an example. GPS positioning, navigation, and timing have become an integral part of daily life, supporting transportation and communications systems vital to the aviation, merchant marine, cargo, cellular phone, surveying, and oil exploration industries. Everyday activities such as banking, mobile phone operations, and even the control of power grids are facilitated by the accurate timing provided by GPS. Understanding the risks of space weather to GPS and the many economic sectors reliant upon it, as well as how to build resilience, was the focus of a policy workshop organized by the American Meteorological Society (AMS) and held on 13–14 October 2010 in Washington, D. C. The workshop brought together a select group of policy makers, space weather scientists, and GPS experts and users. Arif Alikhan, assistant secretary for policy development in the U.S. Department of Homeland Security, kicked off the meeting by stressing that authorities should see GPS and resilience through an all-hazards lens rather than plan for each emergency scenario on a case-by-case basis. Whether a GPS signal error or disruption is caused by a solar storm, an intentional jammer, or some other source, government and industries need to plan to respond to the incident and restore capability as quickly as possible, although, Alikhan remarked, “The number of potential scenarios is infinite, and we have neither the time nor resources to plan against them.” Alikhan suggested that risk managers conceptualize the scope of critical assets in need of protecting through a resilience and risk analysis framework. He recommended that decision makers take an inventory of all functions provided for by their institutions“ use of GPS. Next, through risk-informed prioritization, planners can ascertain whether a backup is really needed for any services provided by GPS. “In this fiscal environment,” Alikhan said, “we will need to shrink the haystack, or size of the problem, in order to be effective.” Because the interdependencies of critical infrastructures are not fully appreciated by the public and private sectors, he stressed that a mix of governmental, commercial, and international stakeholders should develop plans and procedures to make systems more resilient. The remainder of the workshop was organized around discussions in three sessions: (1) identifying the vulnerability of GPS technologies and services to space weather, (2) identifying how this vulnerability affects users who depend on GPS, and (3) developing opportunities and policies for building resilience. In the first session, participants agreed that the vulnerability of GPS needs to be defined for different segments (e.g., satellites, signals, users). While some understanding of user needs exists, the definition of user requirements needs more clarification because space weather events will affect some technologies more than others. Also, a threat assessment would be valuable to best understand how severe the impacts might be and what mitigation options are available. With the recent news that Google™ is building self-driving robotic cars that depend on GPS, trying to capture possible future vulnerabilities is extremely challenging. During a debate on how much to stress the impact of a solar flare as massive as the 1859 Carrington event, many warned that while the public should be made aware of such a potential occurrence, it should not govern planning, since such a doomsday scenario is uncertain and expected to happen only very infrequently. When discussing in the second session how users of GPS are affected, participants discovered that communicating with GPS stakeholders and users is a challenge because many do not understand the impacts of adverse space weather. In particular, many of the service providers and end users of GPS were not in business during the previous solar maximum and therefore are not familiar with space weather hazards. To help remedy this, outreach approaches were discussed, and some participants argued that the space weather community should anticipate the needs of the users. Others instead urged the space weather community to deal only with the service providers—not end users—and ask them rather than tell them what they need. Despite this debate, there was broad agreement that space weather researchers should develop better measurements and predictions of the ionosphere. In addition, participants agreed that scintillation specifications and predictions would be useful to many users of GPS. Improved predictions would be possible by installing more dual-frequency stations and scintillation monitors, they noted. The workshop concluded with a discussion of policy options for building resilience. Participants debated what measures could be taken, such as developing new policies, investing in research and development, changing industry practices, and public and private sector collaboration. Scott Pace, director of George Washington University“s Space Policy Institute, stressed in his presentation that stakeholders and disaster planners should focus on three aspects: prediction, detection, and mitigation. Better space physics/heliophysics science is needed, and it was recommended that this be a top priority for the Solar and Space Physics decadal survey, which sets future nationwide research targets and is currently under review by the U.S. National Research Council. Findings and recommendations from the workshop will be published in a report by AMS. The results will be widely distributed to various stakeholders, including policy makers, GPS service providers, federal agencies, research communities, and international organizations. Genene Fisher is a senior policy fellow in the American Meteorological Society's Policy Program. E-mail: [email protected]

Radiation Belt Storm Probes: A New Mission for Space Weather Forecasting

We present an analysis of the users of space weather information based on 2783 responses to an online survey among subscribers of NOAA's Space Weather Prediction Center e‐mail services. The survey requested information focused on the three NOAA space weather scales: geomagnetic storms, solar radiation storms, and radio blackouts. Space weather information is most commonly obtained for reasons of human safety and continuity or reliability of operations. The information is primarily used for situational awareness, as aid to understand anomalies, to avoid impacts on current and near‐future operations by implementing mitigating strategies, and to prepare for potential near‐future impacts that might occur in conjunction with contingencies that include electric power outages or GPS perturbations. Interest in, anticipated impacts from, and responses to the three main categories of space weather are quite uniform across societal sectors. Approximately 40% of the respondents expect serious to very serious impacts from space weather events if no action were taken to mitigate or in the absence of adequate space weather information. The impacts of space weather are deemed to be substantially reduced because of the availability of, and their response to, space weather forecasts and alerts. Current and near‐future space weather conditions are generally highly valued, considered useful, and generally, though not fully, adequate to avoid or mitigate societal impacts. We conclude that even among those receiving space weather information, there is considerable uncertainty about the possible impacts of space weather and thus about how to act on the space weather information that is provided.

Presentation and validation of the internal charging risk forecast in the PAGER framework

The Time and Frequency Division of the National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce (DOC), was tasked with fulfilling Section 4, Part (i) of the Position, Navigation and Timing (PNT) Executive Order that was signed by the President on February 12, 2020. The Executive Order states that Within 180 days of the date of this order, the Secretary of Commerce shall make available a GNSS-independent source of Coordinated Universal Time, to support the needs of critical infrastructure owners and operators, for the public and private sectors to access. Although the Executive Order does not specifically provide an accuracy requirement, this report assumes an accuracy requirement of 1 ?s with respect to Coordinated Universal Time (UTC). This specification is assumed because numerous critical infrastructure timing systems in the United States are now heavily dependent on signals received from the Global Positioning System (GPS) satellites that routinely provide sub-microsecond accuracy, and other UTC sources that deliver time at comparable accuracy levels are needed to alleviate or reduce these dependencies. This report was written to describe, propose, and recommend technical methods that NIST has already implemented, or can potentially implement, to fulfill Section 4, Part (i) of the PNT Executive Order.

The Visible Infrared Imaging Radiometer Suite (VIIRS) is a key instrument onboard the Suomi NPP (S-NPP) and the NOAA-20 satellites that provides state-of-the-art Earth observations for ocean, land, aerosol, and cloud applications. VIIRS Reflective Solar Band (RSB) Sensor Data Records (SDR, or Level 1b products) are calibrated and produced independently by The National Oceanic and Atmospheric Administration (NOAA) and the National Aeronautics and Space Administration (NASA) VIIRS science teams. Multiple versions of S-NPP and NOAA-20 VIIRS SDRs are available to date. This study evaluates the long-term calibration stability, biases, and inter-channel consistency of S-NPP and NOAA-20 VIIRS SDRs generated by NOAA and NASA over Deep Convective Clouds (DCC) to support downstream applications, especially climate data record studies. Five VIIRS RSB SDRs were analyzed in this study: (1) NOAA version 2 S-NPP VIIRS reprocessed SDRs (NOAA-NPP-V2, 2012–2020), (2) NASA Collection 1 S-NPP VIIRS SDRs (NASA-NPP-C1, 2012–2021), (3) NASA Collection 2 S-NPP VIIRS SDRs (NASA-NPP-C2, 2012–2021), (4) NOAA constant F-factor calibrated NOAA-20 VIIRS SDRs (NOAA-N20-ConstF, 2018–2021), and (5) NASA Collection 2 NOAA-20 VIIRS SDRs (NASA-N20-C2, 2018–2021). The DCC time series analysis results indicate that the calibrations of the three S-NPP VIIRS RSB SDRs are generally stable, with trends within ±0.1%/year for all RSBs, except for M3–M4 (all three S-NPP SDRs) and I3 (NASA-NPP-C1 only). The calibration of NASA-NPP-C2 SDRs is more uniform at individual detector levels. NOAA-NPP-V2 and NASA-NPP-C1 SDRs exhibit non-negligible time-dependent detector level degradation in M1–M4 (up to 1.5% in 2020–2021), causing striping in the SDR imagery. The biases between NOAA and NASA S-NPP VIIRS RSB SDRs are from 0.1% to 2.4%. The calibrations of the two NOAA-20 VIIRS RSB SDRs are also generally stable, with trends within ±0.16%/year. Small downward trends were observed in the visible and near-infrared (VIS/NIR) bands, and small upward trends were observed in the shortwave infrared (SWIR) bands for both NOAA and NASA NOAA-20 SDRs. The biases between NOAA and NASA NOAA-20 VIIRS RSB SDRs are nearly constant over time and within ±0.2% for VIS/NIR bands and ±0.7% for SWIR bands. There exists large inter-satellite biases between S-NPP and NOAA-20 VIIRS SDRs, especially in the VIS/NIR bands (up to 4.5% for NOAA SDRs and up to 7% for NASA SDRs). In addition, the DCC reflectance of S-NPP VIIRS RSB spectral bands is more consistent with that of the SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) than that of NOAA-20. Bands M4 and M9 seem out of family in all five S-NPP and NOAA-20 RSB SDRs evaluated.

A review of selected experimental results relevant for the use of cosmic ray records in Space Weather research is presented. Interplanetary perturbations, initiated in the solar atmosphere, affect galactic cosmic rays. In some cases their influence on the cosmic ray intensity results in data signatures that can possibly be used to predict geomagnetic storm onsets. Case studies illustrating the complexity of the cosmic ray effects and related geomagnetic activity precursors are discussed. It is shown that some indices for cosmic ray activity are good tools for testing the reliability of cosmic ray characteristics for Space Weather forecasts. A brief summary of the influence of cosmic rays on the ozone layer is also given. The use of cosmic ray data for Space Weather purposes is still in its infant stage, but suggestions for both case and statistical studies are made.

The parallel mean free path of solar energetic particles (SEPs), which is determined by physical properties of SEPs as well as those of solar wind, is a very important parameter in space physics to study the transport of charged energetic particles in the heliosphere, especially for space weather forecasting. In space weather practice, it is necessary to find a quick approach to obtain the parallel mean free path of SEPs for a solar event. In addition, the adiabatic focusing effect caused by a spatially varying mean magnetic field in the solar system is important to the transport processes of SEPs. Recently, Shalchi presented an analytical description of the parallel diffusion coefficient with adiabatic focusing. Based on Shalchi's results, in this paper we provide a direct analytical formula as a function of parameters concerning the physical properties of SEPs and solar wind to directly and quickly determine the parallel mean free path of SEPs with adiabatic focusing. Since all of the quantities in the analytical formula can be directly observed by spacecraft, this direct method would be a very useful tool in space weather research. As applications of the direct method, we investigate the inherent relations between the parallel mean free path and various parameters concerning physical properties of SEPs and solar wind. Comparisons of parallel mean free paths with and without adiabatic focusing are also presented.

The Air Force Office of Scientific Research recognizes of the importance of space weather to global technological infrastructure, placing a strong emphasis on targeted space physics research and development in partnership with other US federal agencies. This is exemplified by AFOSR participation in the interagency National Space Weather Program led by the National Science Foundation, the Community Coordinated Modeling Center for space weather at NASA Goddard Space Flight Center, international partnerships such as the Air Force Research Laboratory’s International Research Initiative, and recent DoD Multidisciplinary University Research Initiatives in space weather.KeywordsSpace weatherspace physicsspace environments and effects

Over 160 scientists and students from more than a dozen countries attended the Chapman Conference on Space Weather: Progress and Challenges in Research and Applications to hear 70 talks and peruse 150 posters documenting achievements made during the first 5 years of the National Space Weather Program (NSWP).Since the advent of the NSWR, space weather research has expanded from a semi‐private activity, pursued mostly to address operational concerns of industries and military branches affected by space weather, to a broad subject pursued in part for its capacity to integrate research across the divisions of the SPA community.

Space weather refers to the conditions and processes occurring in space which have the potential to affect the near Earth environment. Space weather processes can include changes in the interplanetary magnetic field, coronal mass ejections from the Sun, and disturbances in Earth's magnetic field. The effects of space weather can range from damage to satellites to disruption of power grids on Earth.