NOAA, 2019. Solar Radiation Storm. Space Weather Prediction Center, National Oceanic and Atmospheric Administration (NOAA). Accessed 16 October 2020.
" }, "editorialNote": { "en": [ "source:UNDRR HIPS" ] }, "scopeNote": { "en": [ "The Earth’s magnetic field and atmosphere generally protect life on Earth from this particle radiation, but that shielding depends on latitude, magnetic field strength and direction. In the polar regions, the magnetic field lines intersecting the Earth’s surface allow lower energy particles to penetrate into the atmosphere. Solar radiation storms thus often result in polar cap events (PCA), which occur in limited areas around geomagnetic poles; they may last more than a week (NOAA, 2019). Higher energy particles can penetrate the magnetic field and reach spacecraft orbiting at lower latitudes, in particular the International Space Station. High altitude orbits such as the geosynchronous orbit used by spacecraft delivering many commercial and governmental services are not protected by the magnetic field. A factor of criticality in a radiation storm is the energy spectrum of the solar protons. High-energy protons cause single event upsets in spacecraft electronics and increase the harmful radiation dose of exposed human beings, such as in manned spaceflights. Lower energy protons have a severe impact on the polar ionosphere and affect High Frequency propagation at high latitude. The severity of radiation storms can thus be characterised by the flux of charged particles (typically as a 5-minute average) above a given energy threshold such as 10 or 100 MeV. For example, the National Oceanic and Atmospheric Administration (NOAA) scale characterises a radiation storm as extreme when the 5-minute flux above 10 MeV exceeds 105 particles•s- 1•sr-1•cm-2. In large magnitude solar eruptions, high-energy events may last only a few hours while low-energy events may last up to a week (NOAA, 2019). Solar radiation storms occur when a large-scale magnetic reconfiguration, causing a coronal mass ejection and often an associated solar flare, accelerates charged particles in the solar atmosphere to very high velocities. The most common particles are protons, but ions of other low mass (helium to iron) elements are often present and contribute significantly to radiation damage. All these ions can be accelerated to large fractions of the speed of light. At these velocities, the particles can traverse the 150 million km from the Sun to Earth in just tens of minutes or less. When they reach Earth, the fast-moving ions penetrate the magnetosphere that shields Earth from lower energy charged particles. Once inside the magnetosphere, low energy (<1 GeV) particles are guided down the magnetic field lines and penetrate into the atmosphere near the north and south poles (NOAA, 2019)." ] }, "inScheme": [ { "id": "http://connectivity-hub.com/terms/", "title": { "en": "Climate Connectivity Taxonomy" } } ], "inSchemeAll": [ { "id": "http://connectivity-hub.com/terms/" } ], "topConceptOf": [ { "id": "http://connectivity-hub.com/terms/", "title": { "en": "Climate Connectivity Taxonomy" } } ], "@context": { "@version": 1.1, "id": "@id", "type": "@type", "@vocab": "http://www.w3.org/2004/02/skos/core#", "xsd": "http://www.w3.org/2001/XMLSchema#", "dct": "http://purl.org/dc/terms/", "dc": "http://purl.org/dc/elements/1.1/", "schema": "https://schema.org/", "vann": "http://purl.org/vocab/vann/", "ldp": "http://www.w3.org/ns/ldp#", "owl": "http://www.w3.org/2002/07/owl#", "title": { "@id": "dct:title", "@container": "@language" }, "dc:title": { "@id": "dc:title", "@container": "@language" }, "dc:description": { "@id": "dc:description", "@container": "@language" }, "description": { "@id": "dct:description", "@container": "@language" }, "license": { "@id": "dct:license", "@container": "@language" }, "issued": { "@id": "dct:issued", "@type": "xsd:date" }, "created": { "@id": "dct:created", "@type": "xsd:date" }, "modified": { "@id": "dct:modified", "@type": "xsd:date" }, "creator": "dct:creator", "publisher": "dct:publisher", "preferredNamespacePrefix": "vann:preferredNamespacePrefix", "preferredNamespaceUri": "vann:preferredNamespaceUri", "isBasedOn": "schema:isBasedOn", "source": "dct:source", "prefLabel": { "@container": "@language" }, "altLabel": { "@container": [ "@language", "@set" ] }, "hiddenLabel": { "@container": [ "@language", "@set" ] }, "definition": { "@container": "@language" }, "note": { "@container": [ "@language", "@set" ] }, "changeNote": { "@container": [ "@language", "@set" ] }, "editorialNote": { "@container": [ "@language", "@set" ] }, "historyNote": { "@container": [ "@language", "@set" ] }, "scopeNote": { "@container": [ "@language", "@set" ] }, "notation": { "@container": "@set" }, "example": { "@container": "@language" }, "narrower": { "@container": "@set" }, "related": { "@container": "@set" }, "relatedMatch": { "@container": "@set" }, "narrowerTransitive": { "@container": "@set" }, "broaderTransitive": { "@container": "@set" }, "broadMatch": { "@container": "@set" }, "narrowMatch": { "@container": "@set" }, "closeMatch": { "@container": "@set" }, "exactMatch": { "@container": "@set" }, "hasTopConcept": { "@container": "@set" }, "inScheme": { "@container": "@set" }, "topConceptOf": { "@container": "@set" }, "deprecated": { "@id": "owl:deprecated", "@type": "xsd:boolean" }, "isReplacedBy": { "@id": "dct:isReplacedBy", "@container": "@set" } } }