Space Weather Impact on Earth in February and Early March 2023

The first few months of this year have been very busy for space weather prediction centres. Aurora regularly occurs in latitudes between 60-75 degrees and can, therefore, be seen in countries like Iceland, and northern parts of Sweden, Finland, Norway, Russia, Canada, and Alaska, and southern Greenland. However, through February and March, some may have been witnessing the beautiful aurora in unusual places like Germany and the UK whilst others have been busy paying attention to activities happening on the Sun affecting Earth and the space environment between them (i.e. space weather) and preparing for warnings for potential impact on critical infrastructure.

Every day scientists and space agencies around the world are closely monitoring the activity of the Sun in order to ensure the safety of our technology dependent society. Ground based instruments and satellites are used to study the behaviour of the Sun and its impact on Earth and the space environment. It is crucial to understand space weather in order to mitigate the risks they pose to our society and space exploration efforts.

The Sun has an 11-year solar cycle going from solar minimum (i.e., low activity on the Sun) to solar maximum (i.e., high activity on the Sun). The Sun is currently in what is named Solar Cycle 25 and is increasingly getting closer to solar maximum predicted to occur in 2025 [1]. This means that prediction centres will increasingly see more activity on the Sun that can potentially pose low or high risk to our critical infrastructure. Prediction centres such as The National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (NOAA SWPC) and space agencies like The European Space Agency Space Weather Office (ESA) have already announced the occurrence of several space weather events and alerted against possible impact on industries such as the aviation industry. Luckily, despite high activity on the Sun in February and March, many of these activities have either not been situated directly towards Earth or they have been of low intensity. This means that although scientists have been able to see intense space weather events these have had little to no impact on Earth.

Aurora in Denmark, UK and the U.S.

On the 15 February 2023, a Coronal Mass Ejection (CME) was observed departing the Sun with an Earth-directed component. It was anticipated to arrive near mid-to-late day on the 17 February. Due to this observation, a G1-Minor Geomagnetic Storm watch was issued for the 16 and 17 February. This was followed by an additional G2-Moderate Geomagnetic Storm watch for the 18 February [2]. The warnings were issued for northern latitudes alerting the possibility of visible auroras in e.g., Germany, Denmark, UK, and places in the U.S. like Idaho and New York. An additional alert was issued for possible effects on communication and other systems [3+4].

A Geomagnetic storm is a type of space weather event causing major disturbances on the Earth’s magnetic field due to activities on the Sun [5]. They can either be caused by an interaction between charged particles from the solar wind and the Earth’s magnetic field or due to a direct connection between the Sun’s and Earth’s magnetic field [6]. The storms are classified in a scale from G1-G5, wherefrom G1 is a minor event and G5 is an extreme event [7]. The solar wind is a stream of charged particles flowing outwards from the Sun and is made of plasma.

Solar flare causing temporary radio blackouts

Two days after the warning, on 17 February, an X2-class solar flare was registered during a Geomagnetic Storm watch. According to an alert from NOAA SWPC the solar flare caused a sun storm lasting 1 hour and 12 minutes. The flare ionized the exosphere (i.e., the top layer of Earth’s atmosphere) causing temporary R1-minor and R2-moderate radio blackouts on the sunlit side of Earth [8+9]. Due to this, operators in e.g., the maritime and aviation industries may have noticed a loss of signal and other propagation effects at frequencies below 30 MHz lasting for more than an hour after the impact of the solar flare.

Image credit: NASA/SDO, captured by NASA’s Solar Dynamics Observatory: X2-class solar flare erupting on 17. February 2023.

Space Weather events continuing into March

Throughout the last days of February, CMEs and high-speed solar wind caused fluctuations of geomagnetic storms going from G1-minor to G3-strong and back causing visible aurora. These types of space weather events do, however, only seem to be the beginning. The following month, on 5 March, solar wind caused a weak G1-Minor Geomagnetic Storm. According to the Met Office Space Weather Operations Centre (MOSWOC), predictions indicated that the fast solar wind would decline in speed through the 6 and 7 of March, but predictions also indicated that it would increase again on the 8 of March. On the 13 of March a S1-minor solar radiation storm began followed by a G2-moderate geomagnetic storm occurring the 15 of March. Due to CME glances, G1-minor geomagnetic storm watches have been issued by NOAA SWPC for the rest of March [11-13].

A solar radiation storm, sometimes called a Solar Energetic Particle (SEP) event, occur when a large-scale magnetic eruption on the Sun causes an intense inflow of radiation from the Sun carried out into the space environment. These events are typically seen carried out from the Sun through e.g., CMEs or solar flares. Solar radiation storms are classified in a scale from S1-S5, where S1 is a minor event and S5 is extreme event [7].

Space weather can create beautiful events like the aurora and although some may call us ‘lucky’ to see such events around the world it can unfortunately affect our critical infrastructure. In these few beginning months of 2023, we have only seen a small impact from space weather events on Earth. However, this is mainly due to the location of these events on the Sun and their intensity. If the intense space weather events were Earth-directed the impact of these events would have looked very different. It is, therefore, important not to only look and focus on the beautiful landscape that space weather can create on Earth but also to be aware and communicate the importance of implementing mitigation measures for these events. However, communication and creating awareness is only the first step. Governments and industries across national borders have to cooperate and work together towards the implementation of these mitigation measures.

About the Author

Shiba Rabiee has an MSc in Risk, Disaster and Resilience with a specialisation in natural- and anthropogenic hazards and vulnerability on earth and in space.

Her Master’s project: “The Martian Residual Crustal Magnetic Fields: A Mitigation Measures Against Space Radiation to Astronauts?”, focused on disaster risk reduction, resilience and sustainability in space - more specifically on Mars - concentrated on disciplines like planetary science and space medicine. Shiba's interest lies in reducing disasters and creating resilient systems and societies in an ethical and sustainable way both on Earth and in space.

Bibliography

[1] NOAA (n.d.): “Hello Solar cycle 25: Analysis determines we are in Solar Cycle 25”, https://www.weather.gov/news/201509-solar-cycle.

[2] NOAA (19.02.2023): “G1-G2 Geomagnetic Storm Watches Issued for 16-17-18 Feb 2023”, https://www.swpc.noaa.gov/news/g1-g2-geomagnetic-storm-watches-issued-16-17-18-feb-2023.

[3] Space.com (20.02.2023): “Sun unleashes massive X2-class solar flare during geomagnetic storm watch (video)”, https://www.space.com/sun-unleashes-x2-solar-flare-video, by Tariq Malik.

[4] ESA (27.02.2023): “Aurora over Wales”, https://www.esa.int/ESA_Multimedia/Images/2023/02/Aurora_over_Wales.

[5] NOAA (n.d.): “Geomagnetic Storms”, https://www.swpc.noaa.gov/phenomena/geomagnetic-storms.

[6] USGS Science for a changing world (n.d.): “What is a magnetic storm?”, https://www.usgs.gov/faqs/what-magnetic-storm.

[7] NOAA (n.d.): “NOAA Space Weather Scales”, https://www.swpc.noaa.gov/noaa-scales-explanation.

[8] Space.com (20.02.2023): “Sun unleashes massiv X2-class solar flare during geomagnetic storm watch (video)”, https://www.space.com/sun-unleashes-x2-solar-flare-video, by Tariq Malik.

[9] Met Office (06.03.2023): “Forecast overview – Space Weather Forecast Headline: Moderate class flares (R1-R2/Minor-Moderate radio blackouts) likely. Change of G1/Minor Storm intervals especially between 06 and 08 Mar.”, https://www.metoffice.gov.uk/weather/specialist-forecasts/space-weather.

[10] NASA (09.06.2011): “Solar Flares: What Does it Take to Be X-Class?”, https://www.nasa.gov/mission_pages/sunearth/news/X-class-flares.html, by Karen C. Fox.

[11] Met Office (06.03.2023): “Forecast overview – Space Weather Forecast Headline: Moderate class flares (R1-R2/Minor-Moderate radio blackouts) likely. Change of G1/Minor Storm intervals especially between 06 and 08 Mar.”, https://www.metoffice.gov.uk/weather/specialist-forecasts/space-weather.

[12] NOAA (15.03.2023): “S1 (Minor) Solar Radiation Storm Event Began 13 March, 2023”, https://www.swpc.noaa.gov/news/s1-minor-solar-radiation-storm-event-began-13-march-2023.

[13] NOAA (15.03.2023): “G2 (Moderate) Storm Levels Reached 15 March, 2023”, https://www.swpc.noaa.gov/news/g2-moderate-storm-levels-reached-15-march-2023.