Sunny, with a mild chance of catastrophe
The COVID-19 pandemic is surely the most disruptive global event since the Second World War. All aspects of life have been impacted, personal and professional. To work from home, stay in touch with loved ones or run a “Virtual Quiz” we have become heavily dependent on video conferencing. More than ever we rely on gizmos and gadgets, but what if suddenly the power went out?
Historically our interest in the Sun was first in ensuring that Helios drove it across the sky and then in the debate of a geo- or helio-centric model of our solar system. Our Sun is often described as a “garden variety” star, not unusually large or small, hot or cold, old or young. Albeit the backdrop to all life on Earth the general public pay little interest in it, apart from whether they need Suncream on. But the Sun is certainly not dull, it is an interesting, complex, powerful, rapidly evolving object which will have a major impact on our technological-reliant modern society.
The Sun is an almost constant source of near-infrared and optical radiation but there is considerable variability at X-ray and radio wavelengths. During these periods of variability highly charged particles are emitted through its solar wind and through gigantic, energetic eruptions called coronal mass ejections. We refer to this broad range of phenomena as ‘space weather’. If the event is Earth-impacting (geoeffective) then it interacts with our magnetic field which gives rise to the ever photogenic northern and southern lights (aurora borealis/australis). However the consequences can also be much more severe including detrimental effects to the electricity grid, satellites, avionics, air passengers, signals from satellite navigation systems and mobile telecommunications. Whilst extreme space weather events are low-probability, they are high impact and have been identified as a risk to the world economy and society.
Whilst it may be popular to describe the COVID-19 pandemic as a “black swan” event this is disingenuous to epidemiologists and risk analysts who have long highlighted the risk of such an event. The same is true of space weather. Added to the UK National Risk Assessment of Civil Emergencies in 2011 extreme space weather is classified at the same likelihood as an emerging infectious disease and consequently mitigation plans and strategies have been, and continue to be, developed.
However the elusive Holy Grail of space weather research is accurate and actionable forecasting. People have been making terrestrial weather forecasts for at least 2,500 years but the modern scientific discipline is credited to Sir Francis Beaufort and Vice-Admiral Robert FitzRoy and the foundation of the Met Office in 1854. Space weather research is a more recent science, but since 2014 the Met Office have run a space weather operations centre to provide 24/7 warnings of space weather for Government, critical national infrastructure providers and the public. To advance the state-of-the-art in space weather forecasting, at the UN General Assembly in September 2019, the Prime Minister announced a new £20M research fund, quadrupling UK space weather research investment.
This Space Weather Instrumentation, Measurement, Modelling and Risk [SWIMMR] programme will develop and deploy new instruments, models and services to support the space weather community and the Met Office. The University of Birmingham’s Space Environment Research Group (SERENE) has developed the Advanced Ensemble electron density (Ne) Assimilation System (AENeAS) which is a state-of-the-art first-principles data assimilation forecast model of the Earth’s upper atmosphere. SERENE have recently started work on two SWIMMR projects to advance, and make operational, the AENeAS model at the Met Office in order to provide space weather forecasts of the upper atmosphere.
One of these projects will address the problems caused by the charged part of the upper atmosphere: disruptions to high frequency (HF) communications for both the military and civil aviation sectors and global navigation satellite signals for navigation. The second one focuses on the neutral atmosphere, and how we can improve satellite orbit forecasting to reduce the uncertainties in satellite collision warnings.
Whilst space weather forecasting is a young science, it is developing rapidly and is of critical importance. Technology has come to our rescue during the COVID-19 pandemic, but extreme space weather is a threat of equal likelihood which could render the same technology inoperable and we must improve our capability to forecast it.
Dr. Sean Elvidge - Lecturer in Space Environment