Space weather is a collective term used to describe hazardous events in the near-Earth space environment that can have an effect on humans and technology in space, causing damage to satellites, and can also have adverse effects on terrestrial power grids. Reliable predictions may help operators to put hardware into a safe mode, avoid maintenance or upgrades, issue alerts, and better understand the reasons for anomalies. The Prediction of Adverse effects of Geomagnetic storms and Energetic Radiation (PAGER) project provides space weather predictions that are initiated from observations of the Sun and predict the radiation environment in space. The project consists of the most advanced numerical and empirical codes from various institutions, including the adaptation of existing codes to perform ensemble simulations. The models include a combination of empirical and physics-based models, and data assimilation is used in the plasmasphere, ring current, and radiation belts. This project provides a new predictive system accounting for corotating interaction region (CIR) and coronal mass ejection (CME) driven storms, including estimates of confidence levels starting from remote solar observations all the way to the near-Earth solar wind conditions and the radiation environment. We also provide estimates of the levels of surface charging and deep dielectric charging for representative satellites and components. Probabilistic predictions allow us to advance the lead time for forecasts of the entire chain of processes up to predictions of several days ahead of the current time. The results of the PAGER project are available on the website: https://www.spacepager.eu/data-products. (c) 2026 The Author(s). Published by Elsevier B.V. on behalf of COSPAR. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).

Space environment models are imperative tools for space weather research and operational forecasting. Two major targets in the space weather enterprise are to advance predictive modeling capabilities and to promptly transition new models to space weather operations. Model assessments are essential to build credibility for potential users, while the approach to model validation depends on user priorities. Precise, transparent and up-to-date evaluations of strengths and limitations of space weather models provide vital guidance toward the progress in understanding of space environment phenomena. It also demonstrates potential of new models to improve state-of-the-art operational space weather forecasting. Therefore, a space weather capabilities assessment is one of the Overarching Activities of the COSPAR International Space Weather Action Teams (ISWAT) initiative. ISWAT Action Teams associated with ISWAT domain-focused (S – Space weather origins at the Sun, H - Heliosphere variability, G - coupled Geospace System, plus the newly established cross-domain Sun-to-Geospace - S2G) Clusters, provide pivotal progress in Assessment Overarching Activity. The ISWAT community-wide validation projects include both Modeling Challenges for historic time periods and pre-event real-time ensemble predictions. At the same time, operational space weather forecasting centers perform pre-operational and operational real-time continuous model validations and provide feedback to developers. This Roadmap paper presents a comprehensive overview of successes and lessons learned from validation projects and the transition to operations activities since the previous Space Weather Roadmap (Schrijver et al., 2015) and outlines recommendations for moving forward

The objective of the ESA Space Safety Programme is the protection of our planet, humanity and assets in space and on Earth from hazards originating in Space. The programme incorporates activities in the areas of space weather, planetary defense, space debris and clean space technologies. This paper will focus on the space weather system developments ongoing within the Programme encompassing new measurement systems for space weather phenomena, service development and pre-operational provision. This paper presents an overview of both space and service system developments currently ongoing and next steps.

This paper is the second part of two papers on global coordination in space weather. In this paper the activities of established and emerging international organizations and initiatives related to space weather research and operations are introduced. As shown in the accompanying paper “Global Landscape of Space Weather Observations, Research and Operations”, most of instrumentations for space environment monitoring are operated by each country. On the other hand, it is necessary to integrate the global observation to detect space weather phenomena, and it is essential to coordinate among nations for data sharing, set standard formats and protocols, fill observational gaps, etc. There are multiple international organizations and other actors in the field of space weather, and they have their own purposes and goals. In 2022, three international organizations, WMO, ISES and COSPAR reached an agreement to explore pathways to increased coordination of activities. There is also an emerging movement by various space agencies that fund space weather research missions to establish a forum to share plans and foster discussions leading to possible collaborations that advance understanding and enable progress of space weather operations and applications.

Aims. Our goal is to develop and provide an open end-to-end (Sun to Earth) space weather modeling system, enabling to combine (“couple”) various space weather models in an integrated tool, with the models located either locally or geographically distributed, so as to better understand the challenges in creating such an integrated environment. Methods. The physics-based models are installed on different compute clusters and can be run interactively and remotely and that can be coupled over the internet, using open source “high-level architecture” software, to make complex modeling chains involving models from the Sun to the Earth. Visualization tools have been integrated as “models” that can be coupled to any other integrated model with compatible output. Results. The first operational version of the VSWMC is accessible via the SWE Portal and demonstrates its end-to-end simulation capability. Users interact via the front-end GUI and can interactively run complex coupled simulation models and view and retrieve the output, including standard visualizations, via the GUI. Hence, the VSWMC provides the capability to validate and compare model outputs.

During European Space Weather Week 15 two plenary sessions were held to review the status of operational space weather forecasting. The first session addressed the topic of working with space weather service providers now and in the future, the user perspective. The second session provided the service perspective, addressing experiences in forecasting development and operations. Presentations in both sessions provided an overview of international efforts on these topics, and panel discussion topics arising in the first session were used as a basis for panel discussion in the second session. Discussion topics included experiences during the September 2017 space weather events, cross domain impacts, timeliness of notifications, and provision of effective user education. Users highlighted that a 'severe' space weather event did not necessarily lead to severe impacts for each individual user across the different sectors. Service providers were generally confident that timely and reliable information could be provided during severe and extreme events, although stressed that more research and funding were required in this relatively new field of operational space weather forecasting, to ensure continuation of capabilities and further development of services, in particular improved forecasting targeting user needs. Here a summary of the sessions is provided followed by a commentary on the current state-of-the-art and potential next steps towards improvement of services.

In the framework of the Space Situational Awareness Programme (SSA) of the European Space Agency (ESA), the Space WEather (SWE) segment aims to help end-users in a wide range of SWE affected sectors to mitigate the effects on their systems, reducing costs and improving reliability. In the SWE segment, five Expert Service Centres (ESCs), the SSA Space Weather Coordination Centre (SSCC) and the SSA Space Weather Data Centre (SWE-DC) form the SSA SWE network. This network is providing SWE services to users dependent on space weather conditions. The SWE services are composed of an extensive number of products provided by numerous contributing expert groups. Each product is delivered to the SSA SWE network with a full package of documentation and user guidance. This includes results of validation and verification procedures helping the end-user to identify the appropriate products for each application. The currently diverse procedures for product validation and verification hamper the comparison and evaluation of different products. Therefore, the SWE network aims to harmonize these procedures. Here, an overview of the ESCs product validation assessment and planning for the current activity will be given, including examples of best practice and approaches for common validation and verification procedures.

Participants of the 2017 European Space Weather Week in Ostend, Belgium, discussed the stakeholder requirements for space weather‐related models. It was emphasized that stakeholders show an increased interest in space weather‐related models. Participants of the meeting discussed particular prediction indicators that can provide first‐order estimates of the impact of space weather on engineering systems.