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The Effects of Space Weather. Dr. Ramon E. Lopez Physics and Space Sciences Florida Tech. The Sun is always changing. And this causes changes in Earth’s space environment - Space Weather. Basic Elements of Space Weather:. Invisible radiation Energetic particles Solar wind.
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The Effects of Space Weather Dr. Ramon E. Lopez Physics and Space Sciences Florida Tech
The Sun is always changing And this causes changes in Earth’s space environment - Space Weather
Basic Elements of Space Weather: • Invisible radiation • Energetic particles • Solar wind
Today’s X-ray Data Flares “rated” according to peak flux
More exciting X-ray Data Flares “rated” according to peak flux
Short wavelength (energetic) Solar Emissions and the Ionosphere • X-ray and Ultraviolet wavelengths of solar light are responsible for the formation of the ionosphere under normal circumstances.
Ionospheric Density-Irregularity Prediction Northwest Research Associates, Inc. Short Wave Radio Fadeouts (SWFs) • During a flare x-ray and UV intensities increase dramatically. • Dayside ionosphere density increases • HF radio blackouts
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.
Ions Electrons Energetic Plasma From the Tail Diverts Around Earth Forming the “Ring Current” and Van Allen “Radiation Belts”
Time-out-to-think #1 (Work with your deskmate to arrive at your answer – be prepared to discuss your conclusions.) • Using what you know thus far, rank order the three main causes of space weather in terms of the time order in which they would likely produce effects in the geospace environment. • Photons, solar wind, energetic particles • Photons, energetic particles, solar wind • Energetic Particles, photons, solar wind • Energetic Particles, solar wind, photons • Solar wind, energetic particles, photons
Astronaut Hazards • Had the great storm of 1972 occurred during an Apollo flight, the crew would have received a huge and potentially dangerous dose of radiation
Satellite drag led to the premature reentry of the USA’s first manned space station, Skylab.
Orbit Prediction of debris is very hard and consequences are significant!
Killer Electrons • Storms accelerate some particles to MeV energies • Spacecraft can be lost when there is a high, sustained flux of energetic electrons, such as during the May 1998 storm
Ionospheric Density-Irregularity Prediction GPS L1 L2 Ionosphere GPS Receiver Northwest Research Associates, Inc. R. Viereck, NOAA/SEC Ionospheric Irregularity Effects on Trans-Ionospheric Navigation and Communication Ionospheric irregularities cause phase and amplitude modulation, degrading or disrupting navigation and communication
Power grid effects • Power transmission systems are vulnerable to induction driven currents
Blackout! • The March 1989 Magnetic Storm caused millions of dollars of damages as power systems failed
Confused Homing Pigeons • Homing pigeons, among other species, use the Earth’s magnetic field as an aid to navigation. Severe magnetic storms can have a significant impact on them.
Effects of the January 10, 1997 storm • AP story from USA Today on 1/14/97Date: Wednesday, January 15, 1997 9:12AM • NEW YORK - AT&T Corp. has been working since Saturday (1/11/97) to re-establish contact with an important broadcast satellite about to be sold to Loral Space & Communications Ltd.
The first big space weather event:The storm of August 1859 • September 1, 1859, Richard Carrignton was observing sunspots when “….two patches of intensely bright and white light broke out...” • Magnetic perturbations and other effects of this great storm were recorded and published • 2 years later Balfour Stewart wrote - “... it is not impossible to suppose that in this case our luminary was taken in the act.”
Effects of the storm of August 1859 • Elias Loomis collected and published reports of the storm in the Amer. J. of Sci. • Aurora were reported at New Orleans, Galveston, Key West, and Havana • Telegraph operations in Europe and North America were severely impacted • In some cases, telegraphs worked better using GIC currents alone, without batteries
Space Weather “Customers” are diverse and continue to grow as new technologies emerge that are susceptible to the damaging effects
Predicting Space Weather • We are at the point where physics-based models can reproduce actual events • In the next decade we will be able to model the entire system, from the surface of the Sun to the upper atmosphere of the Earth • This is the goal of the Center for Integrated Space weather Modeling - CISM
Time-out-to-think #3 (discuss with your deskmate to arrive at your answer) • What is the most important space weather effect (and why)? • Satellite damage • Communication disruption • Space radiation to space/air travellers • Navigation failures • Ground induced currents • All of the above