Solar Weather
Region 6 Army MARS would like to thank the scientists and research teams at The University of Massachusetts Lowell Center for Atmospheric Research for providing this valuable resource allowing us to determine the critical frequency (foF2) and maximum usable frequency (MUF).
Other Solar Weather Links of Interest
- DIDBase - Select Station List then EGLIN then year/month/day/time for Ionosonde plot.
- NOAA Solar Weather - Solar Weather plots of Kp and X-Ray and other solar emissions.
- Solen Solar Weather - Good general solar forecast from an individual.
- Solar Ham - SolarHam provides real time solar news, as well as consolidated data from various sources.
Austin Ionosonde foF2 Trend
This is a graph of real-time data from the Austin, TX ionosonde in comparison with historic data from the same site. Updated every 15 minutes.
Eglin AFB Ionosonde foF2 Trend
This is a graph of real-time data from the Eglin AFB, FL ionosonde updated every 15 minutes. This data is 45 minutes old, so move time axis left 45 minutes, i.e. what happened over Eglin Fl will happen over Austin TX, 45 minutes later.
Boulder Ionosonde foF2 Trend
This is a graph of real-time data from the Boulder, CL ionosonde updated every 15 minutes.
Latest Austin Ionosonde
This is the latest ionogram captured from the Austin Ionosonde. Updated every 5 minutes. This data is pushed to region6armymars.org as soon as it becomes available.
Unusual D-Region Absorption Patterns
Generally, as planetary K-Index rises, critical frequency is suppressed.
| K-Index | Effect |
|---|---|
| 0-2 | Inactive/Quiet, no impact on HF |
| 3-4 | Unsettled/Active, minor HF fade in higher latitudes |
| 5-6 | HF fade at higher latitudes |
| 7-8 | HF sporadic |
| 9 | HF impossible above 40M |
The X-ray radiation that ionizes the D-layer is the 1.0 - 8.0 A (red) plot. These measurements currently taken from the GOES 16 satelite.
| Flare Category | Effect |
|---|---|
| A1-B9 | No or minor impact on HF |
| C1 | Low absorption of HF signals |
| M1 | Occaisional loss of radio contact on sun-lit side |
| M5 | Limited HF blackout for several minutes |
| X1 | Wide area HF blackout for approx. 1 hr |
| X10 | HF blackout over most of sun-lit side for 1-2 hrs |
| X20 | Complete HF blackout of all sun-lit areas lasting hours |
The red and blue lines correspond to the different measurements taken from the GOES 16 satellite.
| Electron Flux | Effect |
|---|---|
| >1.0e+03 | Partial to complete HF blackout in polar regions |
| <1.0e+03 | Degraded HF propagation in polar regions |
| <1.0e+02 | Minor impacts on HF in polar regions |
| <1.0e+01 | No impacts on HF |
The NOAA Space Weather Prediction Center's proton event threshold is the 10 protons/cm2-s-sr at >=10 MeV (red) plot.
| Proton Flux | Effect |
|---|---|
| 1.0e+06 | Complete HF blackout in polar regions |
| 1.0e+05 | Partial HF blackout in polar regions |
| 1.0e+04 | Degraded HF propagation in polar regions |
| 1.0e+03 | Small effects on HF in polar regions |
| 1.0e+02 | Minor impacts on HF in polar regions |
| 1.0e+01 | Very minor impacts on HF in polar regions |
| 1.0e+00 | No impacts on HF |