A solar flare is a short-lived sudden increase in the intensity of radiation emitted in the neighborhood of sunspots. For many years it was best monitored in the H-alpha wavelength and occurs in the chromosphere, though occasionally white light flares are seen in the photosphere. In modern times the solar X-ray wavelengths are monitored via satellite for solar flares. Flares are characterized by a rise time of the order of minutes and a decay time of the order of tens of minutes. The total energy expended in a typical flare is about 1030 ergs; the magnetic field is extraordinarily high reaching values of 100 to 10,000 gauss. Optical flares in H-alpha are usually accompanied by radio and X-ray bursts and occasionally by high-energy particle emissions. The optical brightness and size of the flare are indicated by a two-character code called "importance." The first character, a number from 1 to 4, indicates the apparent area. For areas of less than 1, an "S" is used to designate a subflare. The second character indicates relative brilliance: B for bright, N for normal and F for faint. A general discussion of solar flares is found in Svestka [1976]. The NOAA National Centers for Environmental Information (formerly NGDC) holds archives for about 80 stations, covering the period 1938 to the present. Currently 5 stations send their data to NGDC Boulder on a routine monthly basis -- the current main observing emphasis for Space Weather has transitioned to Coronal Mass Ejections (CMEs) which directly impact the Earth's geomagnetic field. Solar flares impact the Earth's upper atmosphere and can eject high energy particles that can cause satellite failures. The flare reports were processed and published in the monthly report "Solar-Geophysical Data" and in a different format in the IAU "Quarterly Bulletin on Solar Activity."

The H-alpha Flare Patrol identifies time periods each day when the sun is being continuously monitored by select ground-based solar observatories.

Daily index of solar flare activity.

Collection includes a variety of solar feature datasets contributed by a number of national and private solar observatories located worldwide.

Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This metadata record is currently under construction.[SolarIndices A]

Solar Indices Bulletin is a prompt monthly information product that is distributed within two weeks after the observation month closes. For the month just ended, this 2-page circular tabulates daily values of sunspot numbers and 10.7 cm solar radio flux observed at Penticton (previously at Ottawa); flux measurements at eight other wavelengths are included. Page 2 of the Bulletin gives a table of smoothed monthly mean sunspot numbers for the current solar cycle--a table that begins with smoothed observed values for each month and ends with predictions.

A prominence is a large, bright features extending outward from the sun's surface, often in a loop shapce (Wikipedia)

A Sudden Ionospheric Disturbance (SID) is any of several radio propagation anomalies due to ionospheric changes resulting from solar or geophysical events.

Prominences and filaments are two manifestations of the same phenomenon. Both prominences and filaments are features formed above the chromosphere by cool dense gases held in place by solar magnetic fields. Filaments are observed on the solar disk as dark structures as seen against the hotter chromosphere whereas prominences on the limb appear bright against the perspective of outer space. The scale sizes for prominences and filaments are typically many thousands kilometers. Solar observers typically view prominences and filaments in Hydrogen alpha (656.3 nm). Filaments are sometimes referred to as floccule (plural of flocculus). Prominences and filaments can rapidly form over a period of a day but then typically persist for several weeks and, in some cases, several months. At breakup the gases within these previously stable structures may be explosively released into space in the form of a coronal mass ejection (CME). Space weather operators have and continue to monitor the location and character of prominences and filaments as potential precursors on near-earth geomagnetic activity. (Browse image provided courtesy of http://www.greatdreams.com)

Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This metadata record is currently under construction.[SolarIndices A]