Berdermann, Jens

It is well known that space weather can cause significant disruptions to modern communications and navigation systems, leading to increased safety risks, economic losses, and reduced quality of life. Operators of critical infrastructures (both national and international) are also increasingly aware that extreme space-weather events can have severe impacts on their systems. For example, strong ionospheric disturbances can degrade, and sometimes deny access to satellite positioning, navigation, and timing services, central to the operation of many infrastructures. The mitigation of the effects of space weather on technical systems on the ground and in space, and the development of possible protective measures, are therefore of essential importance. We discuss how space weather drives a wide variety of ionospheric phenomena that can disrupt communications and navigation systems and how scientific understanding can help us to mitigate those effects. We also provide recommendations on further research and collaboration with industrial and governmental partners, which are essential for the development and operation of space weather services.

This paper presents a review on the PECASUS service, which provides advisories on enhanced space weather activity for civil aviation. The advisories are tailored according to the Standards and Recommended Practices of the International Civil Aviation Organization (ICAO). Advisories are disseminated in three impact areas: radiation levels at flight altitudes, GNSS-based navigation and positioning, and HF communication. The review, which is based on the experiences of the authors from two years of running pilot ICAO services, describes empiricalmodels behind PECASUS products and lists groundand space-based sensors, providing inputs for themodels and 24/7manualmonitoring activities. As a concrete example of PECASUS performance, its products for a post-stormionospheric F2-layer depression event are analyzed in more detail. As PECASUS models are particularly tailored to describe F2-layer thinning, they reproduce observationsmore accurately than the International Reference Ionospheremodel (IRI(STORM)), but, on the other hand, it is recognized that the service performance ismuch affected by the coverage of its input data. Therefore, more efforts will be directed toward systematic measuring of the availability, timeliness and quality of the data provision in the next steps of the service development.

ESPAS, the ‘‘near-Earth space data infrastructure for e-science” is a data e-infrastructure facilitating discovery and access to observations, ground-based and space borne, and to model predictions of the near-Earth space environment, a region extending from the Earth’s atmosphere up to the outer radiation belts. ESPAS provides access to metadata and/or data from an extended network of data providers distributed globally. The interoperability of the heterogeneous data collections is achieved with the adoption and adaption of the ESPAS data model which is built entirely on ISO 19100 series geographic information standards. The ESPAS data portal manages a vocabulary of space physics keywords that can be used to narrow down data searches to observations of specific physical content. Such content-targeted search is an ESPAS innovation provided in addition to the commonly practiced data selection by time, location, and instrument. The article presents an overview of the architectural design of the ESPAS system, of its data model and ontology, and of interoperable services that allow the discovery, access and download of registered data. Emphasis is given to the standardization, and expandability concepts which represent also the main elements that support the building of long-term sustainability activities of the ESPAS e-infrastructure.