Space Weather Storms: From Sun to Earth

1. Space Weather Storms: From Sun to Earth Bob Rutledge NOAA Space Weather Prediction Center Boulder, Colorado February 12th, 2013 2013 HRP Investigators’ Workshop – Galveston, TX

2. Outline • The Sun/Solar Cycle • Sequence of Events • Space Weather Phenomena/Impacts • Solar Flares (R Scale) • Radiation Storms (S Scale) • Geomagnetic Storms (G Scale)

3. Sunspots and the Solar Cycle The Sun at Solar Maximum The Sun Now ~27 day full rotation

4. Solar Cycle 24 Predictions Many of the world’s premier solar physicists gather….

5. Solar Cycle Update • Cycle 23 began in May 1996 • Peak in April 2000 with SSN = 120 • Solar Minimum in December 2008 • Solar Cycle 24 Underway

6. Large events can occur with smaller cycles • The largest geomagnetic storms on record occurred • during smaller than average cycles (no causality implied) 1859 Storm 1921 Storm

7. July 2012 Event The Sun on July 23rd – STEREO AHEAD The Sun on July 11th Region 1520 NASA STEREO Positions

8. Sequence of Events Conditions are Favorable for Activity (Probabilistic Forecasts) Event Occurs Coronal Observations

9. Sequence of Events Event Onset/ Ground-Based Observation Analysis and Prediction ACE Observation

10. NOAA Space Weather Scales Radiation Storms Geomagnetic Storms http://www.swpc.noaa.gov/NOAAscales/ Radio Blackouts

11. Solar Flares (Radio Blackouts – R Scale) • Arrival: 8 minutes, photons • Duration: Minutes to 3 hours • Daylight-side impacts • Probabilistic 1, 2, 3-day forecasts • Alerts for exceeding R2 (only) • Summary messages post-event

12. Solar Flare (Radio Burst) Impact on GPS – 6 Dec 2006 ~10 mins

13. Solar Radiation Storms (S Scale) • Arrival: 10’s of minutes to several hours • Duration: hours to days • Short-term warnings pre-onset • Alert for threshold crossing • Summary post-event

14. Historical Radiation Storms

15. Historical Radiation Storms Image Credit – R.A. Mewaldt

16. Geomagnetic Storms (G Scale) • Coronal Mass Ejections (CMEs) create geomagnetic storms • Arrival: ~18 – 96 hours • Duration: Hours to a day or two • Creates ionospheric storms, geomagnetically induced currents, aurora • 1-2 Day watch products based on coronagraph observations and modeling • Short-term (15 -60 min) warnings based on measurement at ACE spacecraft

17. GPS IMPACT – U.S. Federal Aviation Administration (FAA) Wide Area Augmentation System (WAAS) • Intense geomagnetic and ionosphere storms occur on 29 and 30 Oct, 2003 • Acceptable vertical error limits were exceeded for 15 and 11-hour periods METERS

18. Impacts on Electric Power Grid • CME impacts Earth’s magnetic field • Fluctuations generate electric fields on • Earth. These geomagnetically induced • currents (GIC) can flow into power lines • and transformers • Leads to transformer • saturation and • over-heating, voltage • drops, transformer • damage, or protective • device trips Transformer winding failure Transformer exit-lead overheating

19. Geomagnetic Field/Trapped Radiation Image credit NASA SAMPEX Team

20. Galactic Cosmic Rays Image credit Matthia, et al., A Ready-to-Use Galactic Cosmic Ray Model (2013)

21. NASA-MIR, Quiet Day Image credit NASA/JSC Space Radiation Analysis Group

22. NASA-MIR, Additional from Radiation Storm Image credit NASA/JSC Space Radiation Analysis Group

23. NOAA Space Weather Prediction Center Boulder, Colorado www.spaceweather.gov

24. Thank You

25. Backup Slides

26. What is Space Weather? Space weather refers to the variable conditions on the Sun and in the space environment that can influence the performance and reliability of space and ground­based technological systems.. Ionosphere Electromagnetic Radiation Energetic Charged Particles Magnetosphere

27. Event-Driven Product Definitions • Watches; The conditions are favorable for occurrence • Warnings; disturbances that are imminent, expected in the near future with high probability • Alerts; observed conditions meeting or exceeding thresholds

28. Phenomena Reference/Impacts • Solar Flare Radio Blackout (R Scale): • No advance warning • Effects lasts for 10’s of minutes to several hours • Impacts High Frequency (HF) communication on the sunlit side of the Earth • First indication significant S and G scale activity may be possible • Solar Radiation Storm (S Scale): • Warnings possible on the minutes to hours time scale • Elevated levels can persist for several days • Impacts to the health and operation of satellites and International Space Station operations and crew • Impacts High Frequency communication in the polar regions, affecting commercial airline operations • Geomagnetic Storm (G Scale): • Advance notice possible given coronal mass ejection (CME) transit times from Sun to Earth range from just under a day to several days (CMEs being the main driver of significant storms) • In extreme storms, impacts to power grid operations and stability • Impacts to Global Positioning System (GPS) accuracy and availability • Driver of aurora; severe to extreme storms may cause aurora to be visible over most of the lower 48

29. Earth’s Role http://missionscience.nasa.gov/sun/sunVideo_04magnetosphere.html

30. High Impact/Low Frequency Threat… Media Release: Loss of Reactive Power, Voltage Instability Most Likely Outcome from GMD, NERC Report Finds February 29, 2012 ATLANTA – Loss of reactive power is the most likely outcome from a severe solar storm centered over North America, a report released by the North American Electric Reliability Corporation (NERC) finds. Significant losses of reactive power could lead to voltage instability and, if not identified and managed appropriately, power system voltage collapse could occur….. …but is it a 100 year storm…200 year…?

31. July 2012 Event The Sun on July 11th Region 1520

32. Solar Cycle Update