cism summer school 2013 - high altitude …...cism summer school 2013 howard j. singer (noaa/swpc)...
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CISM Summer School 2013
Howard J. Singer (NOAA/SWPC) Based in part on material from:
Harlan E. Spence (BU/CSP) and Terry G. Onsager (NOAA/SWPC)
SPACE WEATHER Effects and Consequences
Space is not a vacuum, but a dynamic and harsh environment with space weather effects and consequences that influence our daily lives.
Geomagnetic Storm Effects on Telegraph Operations - September 3, 1859
Boston (to Portland operator).--"Please cut off your battery entirely from the line for fifteen minutes."
Portland.--"Will do so. It is now disconnected."
Boston.--"Mine is also disconnected and we are working with the auroral current. How do you receive my writing?"
Portland.--"Better than with our batteries on. Current comes and goes gradually."
Boston.--"My current is very strong at times, and we can work better without batteries, as the aurora seems to neutralize and augment our batteries alternately, making the current too strong at times for our relay magnets. Suppose we work without batteries while we are affected by this trouble?"
Portland.--"Very well. Shall I go ahead with business?"
Boston.--"Yes. Go ahead." (Annual of Scientific Discovery, ed. by D.A. Wells, Boston, Gould and Lincoln, p414, 1860; Singer, H.J., Magnetospheric Pulsations, Model and Observations of Standing Alfven Wave Resonances, Thesis, UCLA, 1980.)
SW 102: Space Weather Effects
• Scientific understanding is maturing (reality).
• Numerical models permit better views of the global system (virtual reality).
•• Relevance to society is increasing – space weather is a real phenomenon with oftentimes damaging effects and consequences (harsh reality).
Basic Elements of Space Weather: The Sun is a remarkably constant object as viewed in visible light. Each ~million-year-old photon arrives in ~8 minutes. Its irradiance is nearly
constant at 1366 W/m2, varying only fractionally over a solar cycle. Total Solar Irradiance
Gregg Kopp
Basic Elements of Space Weather: The Sun’s invisible radiation (radio, x-ray, gamma ray, UV) is another story; it varies on short and long time scales and what you can’t see can really hurt you! These solar photons (both short and long wavelenghts) can produce profound effects in geospace. Flux proxies are common.
The solar radio flux, originating from atmospheric layers high in the Sun's chromosphere and low in its corona, follows the solar cycle as does the x-ray flux. The flux at 2800 MHz or 10.7 cm wavelength over the entire solar disk is called F10.7 and it is available from continuous routine ground-based measurements. The F10.7 proxy is used, for example, as an input parameter in models for Earth's atmosphere.
Solar x-ray emissions
Sun
Earth
Interplanetary Satellites
Basic Elements of Space Weather:
Solar Wind Earth’s Atmosphere Density: 10 particles/cc – TENUOUS ! 1020 particles/cc
Temperature: 105 K - HOT! 298 K = 25 OC Speed: 400 km/s (1.4 million kph) – FAST! 10 kph
Magnetic Field: 10 nT 30,000 nT
…but other invisible emissions are also critical to space weather! The solar plasma from the hot corona expands into interplanetary space
(solar wind), carrying with it the variable magnetic field of the Sun (IMF). This magnetized plasma encounters the Earth in typically four days.
Yohkoh SXT
The supersonic wind carries mass and energy towards Earth.
(view from dusk; Sun to the left)
But Earth’s magnetic field diverts most of the flow and energy.
A bow shock forms and the slowed turbulent flows skirt us, in the ideal case leaving us with a “closed magnetosphere.”
The flow is continuous, but inherently 3-D and time dependent.
One can imagine that particles and fields are carried continuously along fronts of arbitrary structure.
Many such structures are large compared to the magnetosphere.
All have virtually radial flow, but with arbitrary IMF direction.
When the IMF is parallel to Earth’s field (“northward”) at the “nose”, energy transfer from solar wind to Earth is minimized.
Idealized “Northward” IMF
But when the IMF is anti-parallel to Earth’s field (“southward”), energy transfer from solar wind to Earth is maximized.
Idealized “Southward” IMF
Where IMF and Earth fields are anti-parallel they can connect through magnetic reconnection, “opening” the magnetosphere.
The reconnected field lines permit particles to enter through the magnetic cusps, and are then dragged anti-sunwards.
The open field lines of the long magnetotail “lobes” remain mostly empty of solar wind plasma after leaving the cusp area.
They add to the field of the tail lobes, thereby storing magnetic energy extracted from the solar wind flow.
Eventually, the stored magnetic energy is released through a second reconnection converting magnetic back to plasma energy.
The thermal and bulk flow energy can penetrate deep into geospace on “closed” field lines, coupling to the inner
magnetosphere and to the upper atmosphere/ionosphere.
Electrons Ions
Energetic Plasma From the Tail Diverts Around Earth
Forming the “Ring Current” and Van Allen “Radiation Belts”
Geomagnetic Indices Indicate the Strength and Variability of
Magnetospheric and Ionospheric Currents
Large-Scale Magnetospheric Convection Drives High-Latitude Ionospheric Flows
EPRI, 1996
The Solar Wind Acts as a Generator - The Ionosphere Acts as a Resistor Through Which Current Flows
A Review of Causes and A Preview of Effects • “Invisible” solar photons vary significantly over a solar
cycle and even more strongly on short time scales. These photons (particularly at shorter wavelength) are dangerous to various space systems and people in space, and can modify the ionosphere and disrupt communications.
• Magnetized plasmas of the supersonic solar wind buffet the Earth continuously. While ~90% of the energy is diverted, the other 10% energizes plasmas and drives large electrical currents, often impulsively, producing a large number of deleterious effects for spacecraft and ground systems.
• Shocks produce particles much more energetic than solar wind particles, sometimes traveling a large fraction of the speed of light. These energetic particles can harm space and air travellers and damage space technologies.
• Using what you know thus far, rank order the three main causes of space weather in terms of the time order (first to last) in which they would likely produce effects in the geospace environment.
Time-out-to-think #1 (Work with your deskmate to arrive at your answer –
be prepared to discuss your conclusions.)
1. Photons, solar wind, energetic particles 2. Photons, energetic particles, solar wind 3. Energetic Particles, photons, solar wind 4. Energetic Particles, solar wind, photons 5. Solar wind, energetic particles, photons
EPRI, 1996
How are We Affected by Space Weather?
NASA
Ionosphere L1
L2
GPS Receiver
GPS
R. Viereck, NOAA/SEC Telstar 401
Satellite Systems
Power Transmission Space Habitation
Nav/ Comm Systems
Spacecraft are impacted by energetic solar protons, and inner-magnetospheric particles
Global Positioning Satellite (GPS) Orbits
Approximately 240 Satellites in Geosynchronous Orbit
Low-Earth Orbiting Satellites
Space Stations and Space Shuttles
30
• ~250 S/C @ ~$300M to deploy = $75 billion dollar investment • Revenues ~ $100M/yr per S/C = >$250 billion revenue stream • Operate 24/7 for 10-15 years adapted from M. Bodeau (Boeing)
Satellite Operations
TYPES OF SATELLITE “ANOMALIES” – Usually non-fatal but still COSTLY!
• Total Dose Effects
• Debris
• Surface Charging
• Deep Dielectric or Bulk Charging
• Spacecraft Orientation Effects
• Photonics Noise
• Materials degradation
• Meteorite impact
• Solar Radio Frequency Interference and Scintillation
• Single Event Upsets (SEUs) - a) Galactic cosmic rays, b) Solar proton events
• Spacecraft Drag (<100 km)
Electric Power
• ‘Ground effects of space weather are generally known as GICs (geomagnetically induced currents). GICs are driven by the geoelectric field associated with a magnetic disturbance in electric power transmission grids, pipelines, communication cables and railway equipment.
• When flowing through transformers, the dc-like GIC may cause saturation leading to an increase of the exciting current. Several problems may then arise: an increase of harmonics, unnecessary relay trippings, an increase in reactive power losses, voltage drops, a black-out of the whole system, permanent damage to transformers.
• When flowing from the pipeline into the soil, GIC may increase corrosion of the pipeline, and the voltages associated with GIC disturb the cathodic protection system and standard control surveys of the pipeline.
Geomagnetically Induced Currents
• The most famous GIC failure occurred in the Canadian Hydro-Quebec system during a great magnetic storm on March 13, 1989. The system suffered from a nine-hour black-out. ‘ (from FMI)
EPRI, 1996
Mitigation Against Geomagnetically Induced Currents
Action Lead Time Reliability Reschedule Maintanance 1-2 days > 50% Use Reserve Generation 2-3 hours > 80% Reduce Loading 15-30 minutes > 90%
Examples of possible response to Space Weather information:
Highest priority information for affected industries:
• Continuous solar wind monitor upstream of Earth • Real-time magnetometer observations at auroral latitudes • High time resolution model of electrojet strength and location
Examples of possible response to Space Weather information
International Space Station Radiation Risks
Space Radiation Analysis Group NASA Johnson Space Center
(and now the Moon and Mars!)
Outer Electron Belt Enhancement: electrons: > 500 keV
Solar Energetic Protons: protons: > 10 MeV
South Atlantic Anomaly protons: > 10 MeV
Radiation to Astronauts
M. J. Golightly, NASA JSC
NOAA
Commercial Space Transportation…,
What’s New?
Federal Aviation Administration
Stewart W. Jackson Associate Administrator Commercial Space
Transportation April 25, 2006
The SpaceShip Company
• Formed by Richard Branson (Virgin Group) and Burt Rutan (Scaled Composites).
• Scaled will design, build, and test a fleet of 5 suborbital spaceships and 2 launch aircraft.
• Virgin Galactic will be the operator. – $80 M in deposits from about 610 individuals
• SpaceShipTwo unveiled December 09 • Each vehicle will carry up to 6 passengers and 2
crew. • Initial ticket price to be $200,000. • Spaceship 2 first full space test flight scheduled
for end of 2013
Ionosphere L1
L2
GPS Receiver
GPS
R. Viereck, NOAA/SEC
Ionospheric Irregularity Effects on Trans-Ionospheric Navigation and Communication
Northwest Research Associates, Inc.
Ionospheric Density-Irregularity Prediction
Ionospheric irregularities cause phase and amplitude modulation, degrading or disrupting navigation and communication
1990 1995 2000 2005 2010
Alti
tude
(nau
tical
mile
s)
Year
200
260
320
Hubble altitude with scheduled reboosts
Science operations altitude
Solar Cycle 22 Solar Cycle 23 Solar Cycle 24
Predicted Hubble Altitude for a Strong Solar Cycle 23
Distance below operational altitude
Hubble re-enters without reboost
Withbroe, Director, NASA Space Physics Division
R. Viereck, NOAA
G. Withbroe, NASA
Atmospheric Density Effects on Satellite Orbits
Space Weather “Customers” are diverse and
continue to grow as new
technologies emerge that are
susceptible to the damaging effects
Commercial Space Transportation
Airline Polar Flights Microchip technology
Precision Guided Munitions Cell phones Atomic Clock Satellite Operations Carbon Dating experiments GPS Navigation Ozone Measurements Aircraft Radiation Hazard Commercial TV Relays Communications Satellite Orientation Spacecraft Charging Satellite Reconnaissance & Remote Sensing Instrument Damage Geophysical Exploration. Pipeline Operations Anti-Submarine Detection Satellite Power Arrays Power Distribution Long-Range Telephone Systems Radiation Hazards to Astronauts Interplanetary Satellite experiments VLF Navigation Systems (OMEGA, LORAN) Over the Horizon Radar Solar-Terres. Research & Applic. Satellites Research & Operations Requirements Satellite Orbit Prediction Solar Balloon & Rocket experiments Ionospheric Rocket experiments Short-wave Radio Propagation
• What is the most important space weather effect (and why)?
Time-out-to-think #2 (discuss with your deskmate to arrive at your answer)
1. Satellite damage
2. Communication disruption
3. Space radiation to space/air travelers
4. Navigation failures
5. Ground induced currents
6. All of the above
They are all most important depending
on the customer!
X
?
Model Motivation: A Tropospheric Weather Analogy Observations of typhoons provide advance warning in order
to protect property and to assure personal welfare. However, final destination and strength are difficult to
predict – MODELS ARE AN IMPERATIVE!
November 6, 1997
Sun
Earth
?
Coronal Mass Ejection Observed by SOHO LASCO C2 Coronagraph
Coronal mass ejections are observed in the solar wind. However, final destination and strength are difficult to
predict – MODELS ARE AN IMPERATIVE!
BRING ON THE VIRTUAL REALITY!