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RE: Space Weather Forecasting
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The peak of the next sunspot cycle is expected in late 2011 or mid-2012 potentially affecting airline flights, communications satellites and electrical transmissions. But forecasters can't agree on how intense it will be.
A 12-member panel charged with forecasting the solar cycle said Wednesday it is evenly split over whether the peak will be 90 sunspots or 140 sunspots.

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Space weather is a chain of processes originating at the sun, propagated through interplanetary space, interacting with the Earths magnetic field and eventually generating a number of phenomena in the Earths atmosphere. Scientists in Copenhagen are exploring the link between Earths climate and space weather. The suns magnetic field shields us from most of the highly energetic particles coming from space but, depending on solar activity, some of these particles can break through this shield. The European Space Agency has two missions in orbit aimed at understanding the Sun-Earth interaction: the Cluster mission, consisting of four spacecraft measuring variations in the space environment around our planet in 3D, and the solar mission SOHO, monitoring the solar surface round the clock and detecting any changes, notably sun storms heading its way into space.

ESA video (24.2mb, mp4)

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September 1859 solar flare
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Title: Modelling atmospheric effects of the September 1859 solar flare
Authors: Brian Thomas (Washburn Univ.), Charles Jackman (NASA GSFC), Adrian Melott (Univ. of Kansas)
(revised v2)

We have modelled atmospheric effects, especially ozone depletion, due to a solar proton event which probably accompanied the extreme magnetic storm of 1-2 September 1859. We use an inferred proton fluence for this event as estimated from nitrate levels in Greenland ice cores. We present results showing production of odd nitrogen compounds and their impact on ozone. We also compute rainout of nitrate in our model and compare to values from ice core data.
Comment: Revised version including improved figures; Accepted for publication in Geophys. Res. Lett, chosen to be highlighted by AGU

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Newly uncovered scientific data of recorded history's most massive space storm is helping a NASA scientist investigate its intensity and the probability that what occurred on Earth and in the heavens almost a century-and-a-half ago could happen again.
In scientific circles where solar flares, magnetic storms and other unique solar events are discussed, the occurrences of September 1-2, 1859, are the star stuff of legend. Even 144 years ago, many of Earth's inhabitants realized something momentous had just occurred. Within hours, telegraph wires in both the United States and Europe spontaneously shorted out, causing numerous fires, while the Northern Lights, solar-induced phenomena more closely associated with regions near Earth's North Pole, were documented as far south as Rome, Havana and Hawaii, with similar effects at the South Pole.

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RE: Space Weather Forecasting
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If a satellite encounters high-energy particles or other 'space weather' phenomena before ground controllers can take action, on-board electronics could be disrupted, scientific instruments damaged and, in very rare and extreme cases, spacecraft may even be lost. A sophisticated tool in development at ESOC promises to provide effective monitoring and forecasting for any type of mission.
 
But since early 2005, SEISOP (Space Environment Information System for Operations), a space-weather monitoring and forecasting tool under development at ESA's Space Operations Centre, has been successfully providing near-real-time space weather reports for Integral, ESA's gamma-ray space observatory.  

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Ionosphere
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While most weather forecasters focus on the six or seven miles of earth's atmosphere where clouds drift and storms form, Jonathan Makela's sights are set much higher.
Makela, a University of Illinois electrical- and computer-engineering professor, is working on a way to forecast the weather in the ionosphere, the region of Earth's atmosphere found about 45 to 600 miles above the planet.
What happens in the ionosphere — so named because it is heavily ionised by the sun's radiation — can have dramatic effects on satellite communications, air travel and power grids.

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RE: Space Weather Forecasting
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Title: Solar Oscillation Frequency Changes on Time Scales of Nine Days
Authors: S.C. Tripathy, F. Hill, K. Jain, J.W. Leibacher

Researchers establish that global solar p-mode frequencies can be measured with sufficient precision on time scales as short as nine days to detect activity-related shifts. Using ten years of GONG data, they report that mode-mass and error-weighted frequency shifts derived from nine days are significantly correlated with the strength of solar activity and are consistent with long duration measurements from GONG and the MDI/SOHO instrument. However, the correlation varies from year to year and appears to be a complex phenomena. For the short-duration observations, the analysis indicates a higher sensitivity to activity. The researchers also find that magnetic indices behave differently in the rising and falling phases of the activity cycle.

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On July 31st, 2006, a tiny sunspot was born. It popped up from the sun's interior, floated around a bit, and vanished again in a few hours. On the sun this sort of thing happens all the time and, ordinarily, it wouldn't be worth mentioning. But this sunspot was special: It was backward.

"We've been waiting for this. A backward sunspot is a sign that the next solar cycle is beginning" - David Hathaway, a solar physicist at the Marshall Space Flight in Huntsville, Alabama.

"Backward" means magnetically backward.

Sunspots are planet-sized magnets created by the sun's inner magnetic dynamo. Like all magnets in the Universe, sunspots have north (N) and south (S) magnetic poles. The sunspot of July 31st popped up at solar longitude 65° W, latitude 13° S. Sunspots in that area are normally oriented N-S. The newcomer, however, was S-N, opposite the norm.



This tiny spot of backwardness matters because of what it might foretell: A really big solar cycle.
Solar activity rises and falls in 11-year cycles, swinging back and forth between times of quiet and storminess. Right now the sun is quiet.

"We're near the end of Solar Cycle 23, which peaked way back in 2001" David Hathaway.

The next cycle, Solar Cycle 24, should begin "any time now," returning the sun to a stormy state.

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The NCAR team's computer model, known as the Predictive Flux-transport Dynamo Model, draws on research by NCAR scientists indicating that the evolution of sunspots is caused by a current of plasma, or electrified gas, that circulates between the Sun's equator and its poles over a period of 17 to 22 years. This current acts like a conveyor belt of sunspots.

The sunspot process begins with tightly concentrated magnetic field lines in the solar convection zone (the outermost layer of the Sun's interior). The field lines rise to the surface at low latitudes and form bipolar sunspots, which are regions of concentrated magnetic fields. When these sunspots decay, they imprint the moving plasma with a type of magnetic signature. As the plasma nears the poles, it sinks about 200,000 kilometres back into the convection zone and starts returning toward the equator at a speed of about one meter per second or slower. The increasingly concentrated fields become stretched and twisted by the internal rotation of the Sun as they near the equator, gradually becoming less stable than the surrounding plasma. This eventually causes coiled-up magnetic field lines to rise up, tear through the Sun's surface, and create new sunspots.

The subsurface plasma flow used in the model has been verified with the relatively new technique of helioseismology, based on observations from both NSF– and NASA–supported instruments. This technique tracks sound waves reverberating inside the Sun to reveal details about the interior, much as a doctor might use an ultrasound to see inside a patient.

NCAR scientists have succeeded in simulating the intensity of the sunspot cycle by developing a new computer model of solar processes. This figure compares observations of the past 12 cycles (above) with model results that closely match the sunspot peaks (below). The intensity level is based on the amount of the Sun's visible hemisphere with sunspot activity. The NCAR team predicts the next cycle will be 30-50% more intense than the current cycle. (Figure by Mausumi Dikpati, Peter Gilman, and Giuliana de Toma, NCAR.)

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Sunspot Cycle
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The next sunspot cycle will be 30 to 50 percent stronger than the last one, and begin as much as a year late, according to a breakthrough forecast using a computer model of solar dynamics developed by scientists at the National Centre for Atmospheric Research (NCAR) in Boulder, Colorado, US. The research results, funded by the National Science Foundation (NSF) and NASA, were published on-line on March 3 in the American Geophysical Union journal Geophysical Research Letters.

Scientists now predict that the next cycle, known as Cycle 24, will produce sunspots across an area slightly larger than 2.5 percent of the visible surface of the Sun. The cycle is projected to reach its peak about 2012, one-year later than indicated by alternative forecasting methods that rely on statistics.
By analysing recent solar cycles, the scientists also hope to forecast sunspot activity two solar cycles, or 22 years, into the future. The team is planning in the next year to issue a forecast of Cycle 25, which will peak in the early 2020s.
The researchers expect that predicting the Sun's cycles years in advance will lead to more accurate plans for solar storms, which can slow satellite orbits, disrupt communications, and bring down power systems.
The team has verified the information by using the relatively new technique of helioseismology, based in part on observations from NASA instruments. This technique tracks sound waves reverberating inside the Sun to reveal details about the interior, much as a doctor might use ultrasound to see inside a patient.

"Forecasting the solar cycle will help society anticipate solar storms. Important discoveries are being made using helioseismology. Through this technique, we can image even the far side of the Sun" - Paul Bellaire, program director in NSF's division of atmospheric sciences, which funded the research.

The scientists gained additional confidence in the forecast by showing that the newly developed model could simulate the strength of the past eight solar cycles with more than 98 percent accuracy.

"The model has demonstrated the necessary skill to be used as a forecasting tool" - Mausumi Dikpati, NCAR scientist, the leader of the forecast team at NCAR's High Altitude Observatory. The team also includes NCAR scientists Peter Gilman and Guiliana de Toma.

"This is a significant breakthrough with important applications, especially for satellite-dependent societies" - Peter Gilman .

The Sun goes through approximately 11-year cycles, from peak storm activity to quiet, and back again. Solar scientists have tracked these cycles without being able to predict their relative intensity or timing.
Solar storms are linked to twisted magnetic fields that suddenly snap and release tremendous amounts of energy. They tend to occur near dark regions of concentrated magnetic fields, known as sunspots.
The NCAR computer model, known as the Predictive Flux-transport Dynamo Model, draws on research indicating that the evolution of sunspots is caused by a current of plasma, or electrified gas, that circulates between the Sun's equator and its poles over a period of 17 to 22 years.
The plasma acts as a conveyor belt, transporting the imprints of sunspots from the previous two solar cycles. As they return toward the equator, they become stretched and twisted by the internal rotation of the Sun, gradually becoming less stable than the surrounding plasma. This eventually causes coiled-up magnetic field lines to rise up, tear through the Sun's surface, and create new sunspots, beginning the cycle again.

http://www.nsf.gov/

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SunSpot
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Advanced technologies now available at the National Science Foundation's Dunn Solar Telescope at Sunspot, New Mexico, are revealing striking details inside sunspots and hint at features remaining to be discovered in solar activity.

Advanced technologies now available at the National Science Foundation's Dunn Solar Telescope at Sunspot, NM, are revealing striking details inside sunspots and hint at features remaining to be discovered in solar activity.
The Dunn is the nation's premier high-resolution solar telescope. The Association of Universities for Research in Astronomy operates the Dunn as part of the National Solar Observatory under a cooperative agreement with the NSF.

This ultrasharp image of sunspot AR 10810 shows several objects of current scientific interest. G-band bright points, which indicate the presence of small-scale magnetic flux tubes, are seen near the sunspot and between several granules (columns of hot gas circulating upward).


High-resolution image of sunspot Sunspot AR 10810, observed Sept. 23, 2005, 17:03:47 UTC, produced with the new camera attached to the Dunn's adaptive optics system. Credit: Friedrich Woeger, KIS, and Chris Berst and Mark Komsa, NSO/AURA/NSF


The image was built from a series of 80 images, each 1/100th of a second long (10 ms), taken over a period of 3 seconds by a high-resolution Dalsa 4M30 CCD camera in its first observing run after being added to the Dunn. Speckle imaging reconstruction then compiles the 80 images and greatly reduces residual seeing aberrations.

The dark cores of penumbral fibrils and bright penumbral grains are seen as well in the sunspot penumbra (the fluted structures radiating outward from the spot). These features hold the key to understanding the magnetic structure of sunspots and can only be seen in ultra high-resolution images such as this one. Magnetism in solar activity is the "dark energy problem" being tackled in solar physics today.
Normally such features are beyond the grasp of ground-based solar telescopes because of blurring by Earth's turbulent atmosphere.
The Dunn's AO76 system compensates for much of that blurring by reshaping a deformable mirror 130 times a second to match changes in the atmosphere and refocuses incoming light. This allows the Dunn to operate at its diffraction limit (theoretical best) of 0.14 arc-second resolution, rather than the 1.0 to 0.5 arc-second resolution normally allowed by Earth's atmosphere.
The Dunn has two high-order adaptive optics benches, the only telescope in the world with two systems, which enhances instrument setup and operations.

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