What are geomagnetic storms?
Geomagnetic storms are big and rapid disturbances in Earth’s magnetic field caused by its interaction with the solar wind. The Earth’s own magnetic field, generated in its core, creates a kind of shield around the planet, in the absence of which the solar wind would carry away the entire atmospheric layer of the Earth, as it happened on planet Mars many years ago. When an eruption in one of the Sun’s active regions is observed, a stream of plasma gets released into interplanetary space at a speed between 600 and 900 km/sec. Usually, it takes about two days for this stream to reach Earth. In spite of Earth’s magnetic shield, the flow of charged particles manages to penetrate the polar regions and cause the formation of powerful current systems around the equator and polar circles. As a result the beautiful auroras can be observed due to the interaction of solar particles with air molecules. Thus, a magnetic storm is formed. It is strongest around the poles and the Equator and weakens at middle latitudes, where the territory of Bulgaria is located. Hence, we are additionally protected from the strongest changes observed in the magnetic field.
In Bulgaria, the geomagnetic field is registered by one of the oldest observatories on the Balkan Peninsula – The Panagyurishte Geomagnetic Observatory (PGO). The observatory has the most advanced equipment and submits real-time data to both global data centers and NIGGG-BAS’s website for information to all users. The values of the magnetic field are monitored around the clock and the so-called disturbance index is calculated. The data obtained in the last 80 years is used for research by NIGGG-BAS’s scientists.
Information on geomagnetic storms is provided by NIGGG-BAS in the following ways:
- Long-term forecast (monthly) – a calendar published at the beginning of each month in the “News” section of the NIGGG-BAS website and Facebook page, where the colors of the traffic lights mark the days when disturbances and storms are expected.
- Short-term forecast (several hours) – the state of the planetary magnetic field based on satellite data.
- Diagnosis – shows the state of the geomagnetic field on the territory of the country in real time (according to PGO Panagyurishte).