Space weather

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Space Weather

Viereck

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Space weather

  1. 1. Space Weather: What is it? How Will it Affect You? An introduction to Space Weather • What is it? • Where does it come from? • What does it do? Rodney Viereck NOAA Space Environment Center Boulder Colorado
  2. 2. Space Weather: What is it? Space Weather refers to changes in the space environment near Earth Earth Sun Sun: • Energy (386 Billion Billion MegaWatts) released in the form of… • Light • Particles (electrons and protons) • Magnetic Field • Activity Cycles • 27 Days (solar rotation) • ~100 Days Active Region Development • 11 years • 22 years • 88 years
  3. 3. GOES Solar X-Rays Space weather events are usually initiated by a solar flare or a coronal mass ejection During a solar flare, the x-ray irradiance can increase by several orders of magnitude in just a few minutes
  4. 4. Space Weather refers to changes in the space environment near Earth Sun Interplanetary Space: • Solar Wind •Constant outflow from the sun •Electrons and protons • Disturbances from the sun produce waves and shocks in the solar wind Interplanetary Space Space Weather: What is it? Earth
  5. 5. ACE Solar Wind • Solar Wind – Density • 1 to 100 particles per cm3 – Speed • 200 to 800 km/sec
  6. 6. Space Weather refers to changes in the space environment near Earth Magnetosphere Magnetosphere: • Created by Earth’s magnetic field • Deformed by the Solar Wind • Particles (electrons and protons) trapped on magnetic field lines Sun Interplanetary Space Space Weather: What is it? Earth
  7. 7. GOES Particles and Magnetic Field • Protons • Electrons • Magnetic Field
  8. 8. Space Weather refers to changes in the space environment near Earth Magnetosphere Sun Interplanetary Space Ionosphere Ionosphere: • Layer of electrons at the top of the atmosphere (100 – 300 km up) • Formed when extreme ultraviolet light from the sun hits Earth’s Atmosphere • Strongly affected by changes in the magnetosphere • Critical in the reflection and transmission of radio waves Space Weather: What is it? Earth
  9. 9. POES Ionospheric Particles • Auroral Oval – Electrons and Protons collide with the atmosphere – The collisions excite atoms and molecules to produce the aurora
  10. 10. Other Space Weather Terms • Solar Flare: An eruption on the sun that emits light (UV and x-rays) and often particles (electrons and protons). • CME (Coronal Mass Ejection): A disturbance in the solar wind caused by an eruption on the sun. • Solar Wind: The outward flow of electrons, protons, and magnetic field from the sun. • Energetic Particles: electrons and protons that have been accelerated to high speeds. • Geomagnetic Storm: The disturbance in the near-Earth particles and magnetic fields that can upset technological systems and creates aurora. • Radiation Storm: A large flux of solar energetic protons as measured near Earth. • Radio Blackout: An enhancement in the lower ionosphere as a result of large x-ray flares.
  11. 11. Sequence Of Events • Active Region on the Sun Erupts 1. Solar Flare (x-ray) 2. Shock (energetic particles) 3. Corornal Mass Ejection (particles and fields) • X-rays reach Earth in 8 minutes (speed of light) • Energetic Particles reach Earth in 15 min to 24 hours • Coronal Mass Ejection reaches Earth in 1-4 Days
  12. 12. Three Types of Space Weather Storms 1.Radio Blackouts – Solar Flares send out x- rays – Arrive at Earth in 8 minutes – Modify the ionosphere – Disrupt HF radio communication – Impacts: • Airline communication • HF radio operators • DoD Communications • Satellite Communications 2.Radiation Storms – Solar Flares and Coronal Mass Ejections (CMEs) send out Energetic Particles – Arrive at Earth in 15 minutes to 24 hours – Modify the high latitude ionosphere – Disrupt HF radio communication – Impacts: • Airline communication • HF radio operators • DoD Communications – Ionizing radiation penetrates into the atmosphere – Impacts: • Astronauts (radiation) • Satellite failures 3.Geomagnetic Storms – Coronal Mass Ejections (CMEs) send out Magnetic Clouds – Arrive at Earth in 1-4 days – Accelerate particles within the magnetosphere and into the ionosphere – Impacts: • HF radio communication • Radio Navigation (GPS) • Electric Power Grids • Increased Satellite Drag • Aurora
  13. 13. The Sun The Energy Source The sun in X-rays From GOES 12 •The Sun • Rotates every 27 days • Has an 11-year cycle of activity •Flares produce large amounts of x-rays and extreme ultraviolet light but not much visible light An Erupting Prominence A Solar Flare Image from NASA TRACE Satellite Image from NASA SOHO Satellite
  14. 14. Solar Photons (Light) • Visible light (small slow changes) – Most of the energy output – Impacts climate • UV light (medium slow changes) – Affects ozone production and loss • EUV light (large changes) – Affects radio communication – Affects navigation – Affects satellite orbits • X-ray light (Can change by a factor of 1000 in five minutes) – Affects radio communication Solar spectrum Solar variability Atmospheric penetration X-Ray Flare Variability (minutes) Lean
  15. 15. Product for Radio Operators Effect of Solar X-rays on D-Region and HF Propagation. • D-Region Absorption Product based on GOES X-RayFlux (SEC Product) – The map shows regionsaffected by the increased D-region ionization resulting from enhanced x-ray flux during magnitude X-1 Flare TJFR
  16. 16. CMEs (Coronal Mass Ejections) in Interplanetary Space • While Solar flares send out light (mostly x-rays) • CMEs produce… – Energetic particles – Magnetic structures Propagate away from the sun but their paths are modified by the background solar wind and the sun’s magnetic field. Image from NASA SOHO Satellite Image from NASA SOHO Satellite
  17. 17. Magnetosphere What happens when a CME hits Earth? 1. Solar wind is deflected around Earth 2. Deflected solar wind drags Earth’s magnetic field with it 3. Magnetic field lines “reconnect” and accelerate particles 4. Accelerated particles follow field lines to Earth Aurora is produced when particles hit Earth’s atmosphere 1. Solar wind is deflected around Earth 2. Deflected solar wind drags Earth’s magnetic field with it 3. Magnetic field lines “reconnect” and accelerate particles 4. Accelerated particles follow field lines to Earth Aurora Outer Radiation Belt Inner Belt
  18. 18. Energetic Particle Effects Spacecraft Systems • Systems affected – Spacecraft electronics • Surface Charging and Discharge • Single Event Upsets • Deep Dielectric Charging – Spacecraft imaging and attitude systems Polar Satellite Image Degradation SOHO Satellite Image Degradation Spacecraft Surface Charging (NASA animation)
  19. 19. Energetic Particles Effects Radiation Hazard Health Hazards from Energetic Particles • Humans in space – Space Shuttle, International Space Station, missions to Mars • Crew/Passengers in high- flying jets – Concorde carries radiation detectors – Passengers and crew may receive radiation doses equivalent to many chest X rays.
  20. 20. Ionosphere • The particles collide with the atmosphere and produce the Aurora and currents in the ionosphere • As geomagnetic activity increases, the aurora gets brighter, more active, and moves away from the polar regions. – Electric Power is affected – Navigation Systems are affected – Radio Communications are affected Image from NASA IMAGE Satellite
  21. 21. Geomagnetic Storm Effects March 1989 Hydro Quebec Loses Electric Power for 9 Hours Transformer Damage Electric Power Transformer
  22. 22. Aurora • The particles spiral down the magnetic filed lines and collide with the atmosphere to produce the aurora. • Colors indicate the atoms or molecules that are excited by the incoming particles
  23. 23. Geomagnetic Storm Effects Aurora • Intensity and location of the aurora depend on strength of storm • Best time to view is around midnight • No guarantee that aurora will occur G5 G3 G1 Photo by Jan Curtis, http://www.geo.mtu.edu/weather/aurora
  24. 24. Geomagnetic Storms • Disrupt Radio Communications • Impact Electric Power Systems • Impact Satellites• Disrupt Radio Navigations
  25. 25. NASA Animation Sun to Earth • An animation of a space weather event as it starts at the sun and end up at Earth – Solar Flare • Light • Particles • CME – Magnetosphere • Deflects the solar wind • Responds to the disturbance • Accelerates particles – Ionosphere • Accelerated particles collide with the atmosphere producing the aurora
  26. 26. Space Weather Storms Timing and Consequences • At T = 0, A Flare and CME Erupts on the Sun • 8 Minutes later: First blast of EUV and X-Ray light increases the ionospheric density – Radio transmissions are lost • 30 min. to 24 hrs. later: Energetic Particles Arrive – Astronauts are at risk – Satellites are at risk – High altitude aircraft crew are at risk • 1 to 4 Days Later: CME Arrives and energizes the magnetosphere and ionosphere – Electric Power is affected – Navigation Systems are affected – Radio Communications are affected Movie from NASA SOHO Satellite
  27. 27. What Controls the Size a Space Weather Storm? • The Size of Flare or CME – Big solar events tend to make big storms • The Location of the flare site on the SUN – If it is directed at Earth, it is more likely to make a storm – If it toward the west side of the sun, the particles will arrive sooner • The Direction of the Magnetic Field in the CME – If the interplanetary magnetic field is southward, then there will likely be a big storm Note, there does not have to be a solar flare or CME to create a geomagnetic storm
  28. 28. Space Weather Scales • Three Categories – Geomagnetic Storms (CMEs) – Solar Radiation Storms (Particle Events) – Radio Blackouts (Solar Flares) Combs Rabin
  29. 29. How Often Do Space Weather Storms Occur? • Solar Cycle is about 11 Years Radiation Storms 1-4 per month at max Geomagnetic Storms 3-5 per month at max Radio Blackouts 50-100 per month at max Sunspot Number 11-year cycle 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Year EventsPerMonthEventsPerMonth EventsPerMonth
  30. 30. The Solar Cycles of the Past • Sunspots have been recorded for the last 400 years • Note that there were no sunspots for nearly 60 years after 1640 • During the same period, it was very cold in Europe. This is a period called “The Little Ice Age” • Is there a Connection? • Recent studies say there may be Solar Maximum Solar Minimum
  31. 31. Sun and Climate • The sun is the primary engine for weather and the climate • Very large climate changes (Ice ages) are known to be caused by changes in insolation (amount and distribution of sunlight) • The sun is likely responsible for some of the climate change… up to 1960s… but not the rapid increase in temperatures since then. NCAR Climate Model Ammann: SORCE 2003
  32. 32. NOAA POES NOAA GOES NASA ACE NASA SOHO Primary Space Weather Satellites for SEC • ACE – Solar wind composition, speed, and direction – Magnetic field strength and direction • SOHO – Solar EUV Images – Solar Corona (CMEs) • STEREO – CME Direction and Shape – Solar wind composition, speed, and direction – Magnetic field strength and direction • GOES – Energetic Particles – Magnetic Field – Solar X-ray Flux – Solar X-Ray Images • POES – High Energy Particles – Total Energy Deposition – Solar UV Flux NASA STEREO (Ahead) NASA STEREO (Behind) • Events are observed on and near the sun • No measurements until the Particles or CMEs are 99% of the way to Earth • This provides only 30 minutes lead time for CMEs and no lead time for other events
  33. 33. Summary Arrival 8 minutes 15 min. to 24 hrs. 1 to 4 days Time Radio Blackouts Bursts of X-ray and EUV radiation Radiation Storms Energetic Particles (electrons and protons) Geomagnetic Storms When the CME reaches Earth Systems Radio Comm. Satellites Power Companies Affected Airlines Astronauts Radio Comm. Radio Comm. Navigation (GPS) Satellite Drag • Space Weather Storms come in three main categories • Each category originates from different physical processes • Each category arrives at a different speed • Each category affects different users and technologies Space Weather Event

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