|
SFI
166
|
Solar Flux Index
|
DRAO Penticton no longer available, using NOAA data. Intensity of solar radiation measured at 2800MHz (10.7cm). Good indication of the F layer ionization (layer that gives us most of our DX on HF). The higher the number, the greater the level of ionization is, and the higher the frequency. Measured once daily. Note that NOAA recorded SFI for the day is the 2nd (or middle) of the DRAO readings. SFI does correlate to 304A (see graph below).
|
|
SN
138
|
Sunspot Number
|
Sunspot Number provided by NOAA is a reported value from 0 to 250. It is computed using a formula [R=k (10g+s)] by Rudolph Wolf in 1848, where R is the sunspot number; g is the number of sunspot groups on the solar disk; s is the total number of individual spots in all the groups; and k is a variable scaling factor (usually less than 1) that accounts for observing conditions and the type of observing device. NOAA SN does loosely correlate to SFI. Updated once daily.
|
|
A
7
|
Planetary A Index
|
NOAA reported value from 0 to 400. Provides a daily average level for geomagnetic activity. Uses the average of eight 3 hour K-Index values (magnetic value measured in nanotesla or nT) to provide the level of instability in the earth’s geomagnetic field. When used with K-Index: Both high indicates geomagnetic field is unstable, and HF signals are prone to sudden fades, and some paths may close while others open up abruptly and with little warning. High K index/Low A indicates a sudden, abrupt disturbance in the geomagnetic field, which can cause an intense but brief disruption in HF propagation, but can cause an auroral event. Updated once daily.
|
|
K
2
|
Planetary K Index
|
NOAA reported value from 0 to 9. Measures disturbances in the horizontal component of earth's magnetic field. Value in nT is measured using a magnetometer during a three-hour interval, and then converted to a factor. Use with A-Index – sees above to determine HF conditions. Updated eight times daily.
|
|
X-Ray
C1.1
|
Hard X-Rays
|
NOAA reported value from A0.0 to X9.9. Intensity of hard x-rays hitting the earth’s ionosphere. Impacts primarily the D-layer (HF absorption). The letter indicates the order of magnitude of the X-rays (A, B, C, M and X), where A is the lowest. The number further defines the level of radiation. Updated eight times daily.
|
|
304A
143.2
@SEM
|
304 Angstroms
|
NOAA reported value from 0 to unknown. Relative strength of total solar radiation at a wavelength of 304 angstroms (or 30.4 nm), emitted primarily by ionized helium in the sun's photosphere. Two measurements are available for this parameter, one measured by the Solar Dynamics Observatory, using the EVE instrument, and the other, using data from the SOHO satellite, using its SEM instrument. Responsible for about half of all the ionization of the F layer in the ionosphere. 304A does correlate to SFI (see graph below). Updated hourly.
|
|
Pf
50
|
Proton Flux
|
NOAA reported value from 0 to unknown. Density of charged protons in the solar wind. The higher the numbers, the more the impact the ionosphere. Primarily impacts the E-Layer of the ionosphere. Updated hourly.
|
|
Ef
1170
|
Electron Flux
|
NOAA reported value from 0 to unknown. Density of charged electrons in the solar wind. The higher the numbers (>1000), the more the impact the ionosphere. Primarily impacts the E-Layer of the ionosphere. Updated hourly.
|
|
Aurora
2/n=1.99
|
Aurora Normalization
|
Always 1.99 now that Aur is calculated. Will be removed on the next major banner update.
|
|
Bz
3.6
|
Bz Component
|
ACE Satellite reported value from +50 to -50. Strength and direction of the interplanetary magnetic field as impacted by solar activity. Positive is same direction as the earth's magnetic field, and negative is the opposite magnetic polarity. Cancels out earth’s magnetic field when negative, which increases the impact of solar particles in the ionosphere. Updated hourly.
|
|
SW
549.2
|
Solar Wind
|
ACE Satellite reported value from 0 to 1000. Speed (kilometers per second) of the charged particles as they pass earth. The higher the speed, the greater the pressure is exerted on the ionosphere. Values greater than 500 km/sec have impact on HF communications. Updated hourly.
|