Understanding space weather to shield society: A global road map for 2015-2025 commissioned by COSPAR and ILWS

There is a growing appreciation that the environmental conditions that we call space weather impact the technological infrastructure that powers the coupled economies around the world. With that comes the need to better shield society against space weather by improving forecasts, environmental specifications, and infrastructure design. We recognize that much progress has been made and continues to be made with a powerful suite of research observatories on the ground and in space, forming the basis of a Sun-Earth system observatory. But the domain of space weather is vast - extending from deep within the Sun to far outside the planetary orbits - and the physics complex - including couplings between various types of physical processes that link scales and domains from the microscopic to large parts of the solar system. Consequently, advanced understanding of space weather requires a coordinated international approach to effectively provide awareness of the processes within the Sun-Earth system through observation-driven models. This roadmap prioritizes the scientific focus areas and research
infrastructure that are needed to significantly advance our understanding of space weather of all intensities and of its implications for society. Advancement of the existing system observatory through the addition of small to moderate state-of-the-art capabilitiesdesigned to fill observational gaps will enable significant advances.
Such a strategy requires urgent action: key instrumentation needs to be sustained, and action needs to be taken before core capabilities are lost in the aging  ensemble. We recommend advances through priority focus (1) on observation-based modeling throughout the Sun-Earth system, (2) on forecasts more than 12 h ahead of the magnetic structure of incoming coronal mass ejections, (3) on understanding the geospace response to variable solar-wind stresses that lead to intense geomagnetically-induced currents and ionospheric and radiation storms,
and (4) on developing a comprehensive specification of space climate, including the characterization of extreme space storms to guide resilient and robust engineering of technological infrastructures. The roadmap clusters its implementation  recommendations by formulating three action pathways, and outlines needed instrumentation and research programs and infrastructure for each of these. An executive summary provides an overview of all recommendations.Fil: Schrijver, Carolus J.. Lockheed Martin Solar and Astrophysics Laboratory; Estados UnidosFil: Kauristie, Kirsti. Finnish Meteorological Institute; FinlandiaFil: Aylward, Alan D.. University College London; Estados UnidosFil: Denardini, Clezio M.. Centro de Previsao de Tempo e Estudos Climaticos. Instituto Nacional de Pesquisas Espaciais; BrasilFil: Gibson, Sarah E.. HAO/NCAR; Estados UnidosFil: Glover, Alexi. RHEA System and ESA SSA Programme Office; AlemaniaFil: Gopalswamy, Nat. NASA Goddard Space Flight Center; Estados UnidosFil: Grande, Manuel. Univ. of Aberystwyth; Estados UnidosFil: Hapgood, Mike. RAL Space and STFC Rutherford Appleton Laboratory; Reino UnidoFil: Heynderickx, Daniel. DH Consultancy BVBA; BélgicaFil: Jakowski, Norbert. German Aerospace Center; AlemaniaFil: Kalegaev, Vladimir V.. Lomonosov Moscow State University; RusiaFil: Lapenta, Giovanni. KU Leuven; BélgicaFil: Linker, Jon A..Fil: Liu, Siqing. Chinese Academy Of Sciences; República de ChinaFil: Mandrini, Cristina Hemilse. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mann, Ian R.. University of Alberta; CanadáFil: Nagatsuma, Tsutomu. National Inst. of Information and Communications Techn; JapónFil: Nandy, Dibyendu. Center for Excellence in Space Sciences and Indian Institute of Science; IndiaFil: Obara, Tkahiro. Tohoku University; JapónFil: O´brien, T. Paul. Aerospace Corporation; Estados UnidosFil: Onsager, Terrance. NOAA Space Weather Prediction Center; Estados UnidosFil: Opgenoorth, Hermann J.. Swedish Institute of Space Physics; SueciaFil: Terkildsen, Michael. Space Weather Services; AustraliaFil: Valladares, Cesar E.. Boston College; Estados UnidosFil: Vilmer, Nicole. Centre National de la Recherche Scientifique. Observatoire de Paris; Franci