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Again, the aviation industry also makes frequent use of HF Communications which can be degraded by disruptions in the ionosphere.
Sample Scenario: Airline alters polar flight paths to avoid loss of communication due to disturbances in the ionosphere.
In March 2012, we had a sequence of ongoing flares and radiation storms. John, a flight dispatcher called wanting to know if the activity would continue so that he could plan his flight paths to avoid the polar routes. Tom, the forecaster, let him know there was a high probability of another flare and radiation storm from the same sunspot region. Shortly after the phone call, another flare actually occurred and Tom called John back with the radio blackout and radiation storm alerts. John said all went smoothly since he already adjusted flight paths given Tom’s initial advice. Tom told John he could monitor the progress of the blackout on the D-RAP product (see the previous Section on Radio Communication).
Also, systems such as LORAN and OMEGA are adversely affected when solar activity disrupts their signal propagation. The OMEGA system consists of eight transmitters located throughout the world.
Airplanes and ships use the very low frequency signals from these transmitters to determine their positions. During solar events and geomagnetic storms, the system can give navigators information that is inaccurate by as much as several miles. If navigators are alerted that a radiation storm or geomagnetic storm is in progress, they can switch to a backup system. GNSS/GPS signals are affected when solar activity causes sudden variations in the density of the ionosphere. Global Positioning Systems are being used for more precise applications, including mapping of coastlines, surveying for highway construction, airplane navigation, and oil drilling.