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 ViereckNOAA Space Environment Center

Boulder Colorado

1. Space Weather Terms

a. Solar Flare: An eruption on the sun that emits light (UV and x-rays) and often particles (electrons and protons).

b. CME (Coronal Mass Ejection): A disturbance in the solar wind caused by an eruption on the sun.

c. Solar Wind: The outward flow of electrons, protons, and magnetic field from the sun.

d. Energetic Particles: electrons and protons that have been accelerated to high speeds.

e. Geomagnetic Storm: The disturbance in the near-Earth particles and magnetic fields that can upset technological systems and creates aurora.

f. Radiation Storm: A large flux of solar energetic protons as measured near Earth.

g. Radio Blackout: An enhancement in the lower ionosphere as a result of large x-ray flares.

NOAA POES

NOAA GOESNASA ACE

NASA SOHO

L1

2. 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)

a. Events are observed on and near the sun

b. No measurements until the Particles or CMEs are 99% of the way to Earth

c. This provides only 30 minutes lead time for CMEs and no lead time for other events

3. Space Weather:

What is it?Space Weather refers to changes in the space environment near Earth

Earth

Sun

a. 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

Space Weather refers to changes in the space environment near EarthSun

c. 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

3. Space Weather:

What is it?

Earth

Space Weather refers to changes in the space environment near Earth

Magnetosphere

d. 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

Space Weather refers to changes in the space environment near Earth

Magnetosphere

Sun

Interplanetary Space

Ionospheree. 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

4. Sequence Of Events

• Active Region on the Sun Erupts1. 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

5. 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

6. 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

7. MagnetosphereWhat happens when a CME hits Earth?

1. Solar wind is deflected around Earth2. Deflected solar wind drags Earth’s magnetic field with it3. Magnetic field lines “reconnect” and accelerate particles4. 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

AuroraOuterRadiationBelt

InnerBelt

8. 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)

8. 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.

9. 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

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

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

G5G3

G1

Photo by Jan Curtis, http://www.geo.mtu.edu/weather/aurora

Strong Aurora in Colorado

Strong Aurora in Colorado

Later that Morning….

Geomagnetic Storms

• Disrupt Radio Communications

• Impact Electric Power Systems

• Impact Satellites• Disrupt Radio Navigations

During a Solar Max, a Large CME Struck the Moon and Earth Shortly after the End of the Apollo Missions …Fortunately

Geomagnetic Storm EffectsMarch 1989

Hydro Quebec Loses Electric Power for 9 Hours

Transformer Damage

Electric Power Transformer

10. 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

11. How Often Do Space Weather Storms Occur?

• Solar Cycle is about 11 Years

Radiation Storms1-4 per month at max

Geomagnetic Storms

3-5 per month at max

Radio Blackouts50-100 per month at max

Sunspot Number11-year cycle

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000Year

Eve

nts

Per

Mo

nth

Eve

nts

Per

Mo

nth

Eve

nts

Per

Mo

nth

12. 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

SolarMinimum

13. 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

15. Summary

Arrival 8 minutes 15 min. to 24 hrs. 1 to 4 days

Time

Radio BlackoutsBursts 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 technologiesSpace Weather Event