Natural Hazards Phase 3: Volume 10: Space Weather

Abstract:

The Natural Hazards Review project will develop a framework and best practice approach to characterise natural hazards and seek to improve methodologies where current approaches are inefficient. This is to improve energy system infrastructure design and the project is intended to share knowledge of natural hazards across sectors. The project will be completed in three stages. Phase one will focus on a gap analysis. Phase two will look at developing a series of improved methodologies from the gaps identified in phase one, and phase three will demonstrate how to apply these methodologies. Finally, phase 3 will develop a &ldquo;how to&rdquo; guide for use by project engineers.<br /><br />This technical volume addresses:<ul><li>Description of the main phenomena</li><li>Observations and geomagnetic indices</li><li>Methodologies</li><li>Related phenomena; solar energetic particles and groundlevel enhancement, ionospheric scintillation effects on satellite communication and GNSS signal, GIC and pipelines, hazard combinations</li><li>Regulation</li><li>Emerging trends</li></ul>Space weather is defined as a set of processes originating from solar activity that can affect the near-Earth environment. Contrary to solar effects on terrestrial weather which are dominated by the radiation emitted at wavelengths in the visible and infrared parts of the solar spectrum, effects due to space weather are in large part due to contributions from other frequencies of light such as Extreme UV (EUV), X-rays, and gamma (&gamma;) rays, as well as charged particles from the Sun and magnetic fields.Solar flares are the sudden brightening associated with the solar active regions (sunspots where brief releases of magnetic and thermic energies are observed. During these episodes solar energetic particles (SEPs) and magnetised plasma called coronal mass ejections (CMEs) are produced. The aforementioned processes impact the magnetosphere &mdash; the Earth&rsquo;s magnetic shield &mdash; in different ways. CMEs are often responsible for generating the most intense geomagnetic storms, which are temporary disturbances of the magnetosphere. The geomagnetic storm may generate geomagnetically induced currents (GICs) in the ground by inductive effects due to the increased electric field propagating into the atmosphere. In this volume, the impacts of extreme geomagnetic storms and associated GICs are discussed in more detail. The likelihood of extreme geomagnetic storms occurring in the UK is discussed. Then, the different elements required to simulate GIC are outlined. Finally, past GIC analyses for the UK network and the impact expected on transformer systems are summarised.

Publication Year:

2018

Publisher:

ETI

DOI:

https://doi.org/10.5286/ukerc.edc.000534

Author(s):

Ruffenach, A.