Space Weather Causes and Consequences An introduction to Space Weather What is it? Where does it come from? Who is impacted? Rodney Viereck NOAA Space Environment Center Boulder Colorado

Space Weather: What is it? Space Weather refers to changes in the space environment near Earth Earth Sun Sun: Energy released in the form of… Light Particles (electrons and protons) Magnetic Field Activity Cycles 27 Days (solar rotation) 11 years (solar cycle) 22 years 88 years 208 years

Space Weather refers to changes in the space environment near Earth Sun Interplanetary Space: Not quite a vacuum Solar Wind Electrons and protons Magnetic field Disturbances from the sun make waves in the solar wind Interplanetary Space Space Weather: What is it? Earth

Space Weather refers to changes in the space environment near Earth Magnetosphere Magnetosphere: Created by Earth’s magnetic field Deformed by the Solar Wind Not Quite a Vacuum Particles (electrons and protons) trapped on magnetic field lines Sun Interplanetary Space Space Weather: What is it? Earth

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 Critical in the reflection and transmission of radio waves Space Weather: What is it? Earth

Other Space Weather Terms Solar Flare: An eruption on the sun that emits light (UV and x- rays) and often energetic particles. Energetic Particles: electrons and protons that have been accelerated to high speeds and can upset technological systems. Solar Wind: The outward flow of electrons, protons, and magnetic field from the sun. CME (Coronal Mass Ejection): A disturbance in the solar wind caused by an eruption on the sun. Geomagnetic Storm: The disturbance in the Near-Earth environment that can upset technological systems and also creates aurora. Radiation Storm: A large flux of solar energetic protons as measured near Earth that can upset technological systems. Radio Blackout: An enhancement in the lower ionosphere as a result of large x-ray flares that can upset technological systems.

The Sun Solar Flares The sun in X-rays From GOES 12 Rotates every 27 days Has an 11-year cycle of activity An Erupting Prominence A Solar Flare Image from NASA TRACE Satellite Image from NASA SOHO Satellite Hill

Solar Photons (Light) Visible light (small slow changes) –Most of the energy output –Impacts climate UV light (medium slow changes) –Impacts ozone production and loss –May impact climate 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 X-Rays EUV

SEC Product for Radio Operators TJFR Effect of Solar X-Ray Flares on D-Region of Ionosphere and HF Propagation The map shows regions affected by the increased D-region ionization resulting from enhanced x-ray flux during magnitude X-1 Flares

CMEs (Coronal Mass Ejections) in Interplanetary Space Solar flares send out –Light (mostly x-rays) –Energetic particles –Magnetic structures The CME disturbances propagate away from the sun but their paths are modified by the background solar wind and the sun’s magnetic field. Some of these disturbances reach Earth. Images from NASA SOHO Satellite CMEs Hill

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 Onsager

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 Zwickl Spacecraft Surface Charging (NASA animation)

Ionosphere The particle 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

Energetic Particle Effects High Latitude HF Communications Polar airline routes loose ground communications Alternate routes required Uses more fuel Flight delays Sample of Airline Flights Affected: 10/26/00: Lost of HF prior to 75N, re- route off Polar route with Tokyo fuel stop. 15:00 flight now 20:30 11/10/00: Due to poor HF, ORD to HKG flown non-polar at 47 minute penalty 3/30/01-4/21/01: 25 flights operated on less than optimum polar routes due to HF disturbances resulting in time penalties ranging from 6 to 48 minutes 11/25/00: Polar flight re-route at 75N due to Solar Radiation, needed Tokyo fuel stop 11/26/00: Operated non-polar at 37 minute penalty due to solar radiation 11/27/00: Operated non polar at 32 minute penalty due to solar radiation. 11/28/00: Operated non-polar at 35 minute penalty due to solar radiation Polar 2 Polar 3 Polar 1 Polar 4 Polar Airline Routes North Pole Chicago Hong Kong Alaska Radio Blackout During Particle Events TJFR

Geomagnetic Storm Effects March 1989 Hydro Quebec Loses Electric Power for 9 Hours Transformer Damage Electric Power Transformer

Geomagnetic Storm Effects Aurora Intensity and location 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,

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

Space Weather Storms Timing and Consequences At T = 0: A Flare and/or CME Erupts on the Sun 8 Minutes later: First blast of EUV and X-Ray light increases the ionospheric density –Radio transmissions are lost –Navigation errors increase 30 min. to 24 hrs.: Energetic Particles Arrive –Astronauts are at risk –High altitude aircraft crew are at risk –Satellites are at risk –Radio transmissions are lost 1 to 4 Days: CME Arrives and energizes the magnetosphere and ionosphere –Electric power is affected –Navigation errors increase –Radio communications are affected Movie from NASA SOHO Satellite

What Controls the Size a Space Weather Storm? Interplanetary Magnetic Field Earth’s Magnetic Field 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 east 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

Space Weather Scales Three Categories –Geomagnetic Storms (CMEs) –Solar Radiation Storms (Particle Events) –Radio Blackouts (Solar Flares) Combs Rabin

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 per month at max Sunspot Number 11-year cycle Year Events Per Month Murtaugh

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 is Solar Maximum Solar Minimum

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 solar irradiance (amount and distribution of sunlight) The sun is likely responsible for much of the global warming… up to 1960s NCAR Climate Model Ammann: SORCE 2003

Summary Space Weather Storms come in three primary categories Each category arrives at a different time Each category affects different users and technologies Radio Blackouts Bursts of X-ray and EUV radiation Radiation Storms Energetic Particles (electrons and protons) Geomagnetic Storms When the CME reaches Earth Arrival Time8 Minutes30 min. to 24 hrs.1 to 4 days Systems Affected Radio Comm. Navigation Satellites Astronauts Airlines Radio Comm. Electric Power Radio Comm. Navigation