Space weather is a recognised hazard to several critical UK national infrastructures, including the power, pipeline and rail networks, with the potential for substantial (multi-billion pound, many days) economic impact on society. In the context of the SWIMMR project N4 ('Ground Effects Forecasts'), the fundamental driver of impact to these infrastructures is the enhancement of the existing electric field in the ground (the ground electric field, or GEF) during geomagnetic storms, which results from space weather. This GEF acts like an 'unwanted' extra battery applied to an already electrically conducting circuit. The GEF is therefore the source of electrical currents and voltages at the Earth's surface that can upset safe and continued operation of systems such as power grids and their power transformers, and systems for pipeline corrosion avoidance and for railway signalling.

The overall aim of the SAGE project is therefore to be better at now-casting, and for the first time ever, forecasting the GEF in the UK. Flowing from this new capability, the project we propose will also impose this now/forecast GEF on mathematical models of the UK power, pipeline and rail networks. From this we will calculate where the risk points are in each system, under space weather, and how big the impacts might be during severe space weather. This will help government, industry and other stakeholders better understand and mitigate the effects of severe space weather in these key technologies. Such aims (now-casting and forecasting the GEF and quantifying the hazard to ground-based technologies) are fully in line with, and will be leading, in terms of internationally recognised goals in this area, for example as described by the World Meteorological Organisation and the United Nations.

To get to the point where we can propose this ambitious project, UK scientific capability has recently benefited from the NERC 2017 'Highlight Topic' project on 'Space Weather Impacts on Ground-based Systems' (SWIGS: www.geomag.bgs.ac.uk/research/SWIGS/home.html), led by the PI on this present proposal. SWIGS has had the aim of developing the science underpinning the ground effects of space weather, whilst also creating and developing infrastructure models such that space weather impact can be quantified. SWIGS has helped improve a space weather power grid model for the UK, led to the first space weather high pressure gas pipeline model for the country and has produced new insights into space weather impact on the UK rail network. SWIGS collaborators have also developed independent UK capability in physical and empirical modelling of ionospheric and magnetospheric magnetic fields, which drive the GEF, with solar wind input. These novel capabilities will be fully harnessed in the proposal described here.

The SAGE project team comprises internationally known scientists from British Antarctic Survey, British Geological Survey, Imperial College and Mullard Space Science Laboratory (University College London). The project collaborators seek to build on the achievements of the SWIGS team, by coupling several mathematical models constructed during the SWIGS project, representing different elements of the problem, as well as implementing novel forecasting ideas. This will provide an operational now-cast and forecast system in partnership with, and delivered by, Met Office.

This operational system will take measured or forecast solar wind data near the Earth and use these to estimate present and future GEF impacts on the power, pipeline and rail networks of the UK, up to 1 hour ahead. These results will be made available on a series of web displays on systems at the Met Office Space Weather Operations Centre and will be communicated to industry and the public.

Potential Impact:
Space weather can significantly disrupt day-to-day activities by potentially damaging or tripping out power transformers, increasing corrosion in metal pipelines and causing faults on the railway network. Potential economic losses arising from extreme space weather, for example through blackouts, have been estimated at billions of dollars per day for the US. In the UK, the hazard ranks high on the National Risk Register.

Given the potential losses from severe space weather, SAGE will deliver economic and societal impact through Met Office to the electrical power transmission industry, the high pressure gas transmission industry and the rail industry. SAGE, through Met Office, will also deliver impact to government departments and agencies (e.g. GO-Science, BEIS, Cabinet Office) and international bodies concerned with space weather (e.g. WMO, UN, ESA). The outputs of SAGE will be delivered by the Met Office Space Weather Operations Centre (MOSWOC) and will include web displays of nowcasts and forecasts made by the SAGE system, backed by expert knowledge and advice.

Space weather is also a popular topic on social media and in print and broadcast reports. The project team's track record in space weather related outreach, therefore provides a strong base from which to organise outreach events in association with Met Office, and as required by Met Office. Our project is also intended to be synergistic with wider national and international developments, for example in respect of evolving government, industry, insurance company policy on hazards.

SAGE represents internationally leading science that will be of interest to academic colleagues worldwide. The operational aspects of the SAGE project will be of interest to space weather forecasting centres worldwide, including ESA (Europe) and NOAA (US).

Impacts from SAGE will be delivered through Met Office. SAGE has ten major deliverables

DN4.1 A report, based on outputs of NERC funded SWIGS project, that defines the proposed SAGE data streams, research models, operational requirements, code development and integration environment(s) and integrated model architectures

DN4.2 Construction of institute-operational prototype real-time, standalone magnetospheric-conductivity-grid/pipeline models and/or data products produced by these models

DN4.3 Delivery to MOSWOC of prototype real-time, standalone magnetospheric-conductivity-grid/pipeline models and/or data products produced by these models

DN4.4 An interim report on fieldwork activities and improvements in the UK Earth conductivity model

DN4.5 Construction of institute-operational prototype real-time, coupled magnetospheric-conductivity-grid/pipeline models and/or data products produced by these models

DN4.6 Verification of the operational coupled model at institutes (report)

DN4.7 Delivery to MOSWOC of prototype real-time, coupled magnetospheric-conductivity-grid/pipeline models and/or data products produced by these models

DN4.8 Final report on the improved UK conductivity model

DN4.9 Updated and delivered models at final version. Validation and testing of final integrated models at Met Office

DN4.10 Final report on the system - operational through MOSWOC - and reporting on research advances and activities undertaken to advance forecasting skill.