Here it is! A comprehensive guide to some of the various aspects, phenomenon of Space Weather.

Solar Storms are produced when:

"The Sun undergoes a cyclical (~22 year) pattern of magnetic pole reversals observable in the frequency of sunspot activity. This pattern is comprised of two ~11 year solar cycles phases. In the first phase, the sun’s magnetic poles reverse polarity. In the second phase, the sun reverses the magnetic polarity again returning the poles back to their original polarity. Solar storm activity is strongly phase dependent and also very dependent on the position within the solar cycle."

Part 1: Solar Flares Defined

Solar Storms, Solar Flares originate from Sunspots. The Sunspot Number is way of measuring the Solar Activity and Total Solar Irradiance. An increase in the Monthly Observable Sunspot Number increases the likelihood of Solar Flares which are:

"magnetically driven explosions. Approximately 8 minutes after a Solar Flare occurs on the surface of the sun, a powerful burst of electromagnetic radiation in the form of X-ray, extreme ultraviolet rays, gamma ray radiation and radio burst arrives at Earth. The EUV rays heat the upper atmosphere, which causes the outer atmospheric shell to expand. The X-Rays strip electrons from the atoms in the ionosphere producing a sudden increase in total electron content."

The reoccurring 8 minute time period in Space Weather is interesting. Back to Solar Flares, which are classified by scientists according to their brightness in the X-Ray wavelength. 

"The largest observed solar flare was the Carrington white light flare of September 1, 1859. The largest measured solar flare occurred on November 4, 2003 and was rated as an X45. Fortunately this flare only grazed Earth."
Solar Storms consist of three major components: solar flares, solar proton events (SPEs) and coronal mass ejections (CMEs). Not all solar storms produce solar flares, SPEs, and CMEs; but the largest solar storms tend to.

S0 has been tracking the significance of coronal holes in predicting large quakes and the role of galactic cosmic rays can no longer be ignored. Today's news update goes into detail on the function, role of coronal holes in the uptick of large EQs:
Solar Flares are grouped into 5 categories: A-Class, B-Class, C-Class, M-Class and X-Class. Table 2 (above) shows the Intensity.

Part 2: Solar Proton Events (SPE)

On March 7th, 2012: S0 reported on a X-Class Solar Flare that produced a huge CME, Solar Radiation Storm and proton flux.

"Our Sun produces high-energy solar cosmic rays (protons and ions) in Solar Proton Events (SPEs). These particles generally have energies in the range of 10 MeV to 100 MeV. Very energetic SPEs events are also capable of generating near-relativistic protons in the order of 20 GeV. Table 3 (below) gives the arrival time of the protons based on energy level after the solar flare first becomes visible on Earth. In general, SPEs take around an hour to reach Earth. The fastest measured SPE in recent times occurred on January 20th, 2005 with an arrival time of 15 minutes."

"Protons in SPEs and CMEs have energy spectrums ranging from around 10 KeV to above 20 GeV. However, solar events producing protons with energies above 1 GeV are rare.

Due to geomagnetic shielding solar energetic particles with energies less than 100 MeV can only reach the Earth’s atmosphere over Polar Regions where they loose their energy in collision with atoms in the atmosphere creating a cosmic ray shower of particles. If the particles have energies greater than 500 MeV, the cosmic ray shower can penetrate to the planet’s surface."

Part 3: Coronal Mass Ejections (CMEs): Definition can be found Here

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"CMEs are vast clouds of seething gas, charged plasma of low to medium energy particles with imbedded magnetic field, blasted into interplanetary space from the Sun. When a CME strikes Earth, the compressed magnetic fields and plasma in their leading edge smash into the geomagnetic field like a battering ram. This causes a world-wide disturbance of Earth’s magnetic field called a Geomagnetic Storm.

This produces a temporary disturbance of the Earth’s magnetosphere and an equatorial ring of currents, differential gradient and curvature drift of electrons and protons in the Near Earth region. A flood of charged particle and electrons in the ionosphere flowed from west to east, inducing powerful electrical currents in the ground that surge through natural rock. A pitch battle takes place between charged particles and magnetic fields that shake the Earth’s magnetic field over a period of several hours or days. The birthplace of CMEs are often seen to originate near the site of solar flares."

 


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