European Incoherent Scatter Radar Facility (EISCAT) - UK Support Group

EISCAT_3D is an international collaboration that will deliver a new world-leading radar in Europe to monitor and improve understanding of the atmosphere and space weather. It will also provide essential validation for models of the whole atmosphere and for forecasting space weather, which are currently under development. Space weather is the term used to describe natural changes in the upper atmosphere and near-space environment driven by energy from the Sun. As our technology advances and science, industry, and society rely more and more on satellite technology, so our vulnerability to space weather increases. Extreme space weather, which features on the UK Government's 2015 National Risk Register, can cause serious damage to satellites and their associated services, as well as to other critical infrastructures such as power grids and aviation. Long-term trends in space weather also affect the strategies and policies required to protect satellites from the hazards of collision with space debris. However, space weather cannot yet be reliably forecast. To do so requires scientific research to improve understanding and develop improved forecasting models, and better data to inform the research and validate the models. Space weather in the upper atmosphere is influenced by the atmosphere below and there is increasing evidence that space weather also affects "ordinary" weather in the lower atmosphere. The different layers of the atmosphere, from the ground to the edge of space, form a complex coupled system, connected by a wide variety of chemical and dynamical processes, such that it is impossible to understand any one layer of the atmosphere in isolation. Models of the whole atmosphere are now being developed, but there are many processes and feedbacks between layers that are not yet well enough understood to accurately explain or predict their effects. Thus to understand space weather and predict its hazards, and to understand it in the context of the whole atmospheric system, requires a sensitive and versatile instrument that can measure as much of the atmosphere as possible, with good altitude and time resolution over a broad spatial area, in order to study both vertical coupling between atmospheric layers and horizontal structure on the scales affecting individual satellites, planes, and national power grids. EISCAT_3D's new radar technology, combined with the latest digital signal processing, will achieve ten times higher spatial and temporal resolution than the radars it will replace while simultaneously offering, for the first time, continuous measurement capabilities and 3-D imaging. Building on the UK's world-leading expertise in space weather research and its membership of the EISCAT Scientific Association over the last 30 years, this new capability will help address three key scientific challenges (see Objectives): 1. To understand the natural processes behind observed variabilities and trends in the upper atmosphere. 2. To develop and validate space weather forecasting models comparable to those in meteorology. 3. To improve and validate computer models of the whole atmosphere.