Denmark – Northern lights are a stunning example of the effects of solar storms on our atmosphere and while it reveals that solar storms are responsible for sending clouds of electrically charged particles towards Earth, scientists have also found out that the same solar storms remove electrons across large areas.
Researchers at Technical University of Denmark explain that their extensive measurements in connection with a specific solar storm over the Arctic in 2014 indicated that electrons in large quantities are virtually vacuum-cleaned from areas extending over 500 to 1,000 kilometres. This disappearance of electrons is prominent in areas just south of an area with heavy increases in electron density.
Scientist say that the explanation of the phenomenon should probably be found in the geomagnetic processes in the Earth’s magnetic field in a direction away from the Sun. The composition of the magnetic field undergoes dramatic changes in the area between the solar wind and the Earth’s magnetic field, triggering powerful burst of energy.
As the geomagnetic solar storm took place in the ionosphere over the Arctic in February 2014, it was measured via satellites and land-based measuring stations. Among other things, via the GPS network GNET in Greenland–which DTU helps run–via DTU’s geomagnetic measuring stations, the global navigation system GPS, and various American and Canadian satellites. Thus, large data volumes from the solar storm were recorded.
When the magnetic field from solar eruptions hits the Earth’s magnetic field in the ionosphere, their force fields are mixed. Consequently, unstable areas–so-called patches–are created in the Earth’s ionosphere, extending over large areas near the North Pole. The area of patches at the polar cap may extend over 500 to 1,000 kilometres with electron speeds exceeding 1,000 metres per second. This gives rise to surging powerful Northern Lights and creates turbulent conditions.
Knowledge about solar storms are important, as communication with airborne signals via satellites and radio play an increasingly important in society. Solar storms may interfere with GPS satellites and their signals, make radio communication fail, and cause extensive power failures.
The risk of disruptions in the ionosphere is one of the reasons why no routine flights are made over the Arctic, although this would shorten air travel between Europe and America. The high-frequency signals used by commercial flights over Greenland will be subject to interference during solar storms. The ability to predict and take into account these kinds of conditions is therefore important for future commercial air traffic in the region. The same applies to marine traffic in the Arctic.