GEOMAGNETIC STORMS - Lukmaan IAS Blog

GEOMAGNETIC STORMS
written by Lukmaan IAS
THE CONTEXT: In February 2022, Elon Musk’s Starlink lost
dozens of satellites that were caught in a geomagnetic storm a
day after they were launched. The loss of over 40 satellites
in a single solar event has been described as “unheard of” and
“huge”.However, the satellites were designed to burn up on
reentry into the Earth’s atmosphere and did not create debris
in space. The following article explains the phenomenon of
geomagnetic storms from a geographical perspective.

                      GEOMAGNETIC STORMS

A geomagnetic storm is a major and temporary disturbance of
Earth’s magnetosphere. They occur when a surge of the solar
wind (charged particles from the sun) interacts with Earth’s
magnetic field and generates currents in Earth’s upper
atmosphere.

The magnetosphere shields our planet from harmful solar and
cosmic particle radiation, Solar Storms occur during the
release of magnetic energy associated with sunspots (‘dark’
regions on the Sun that are cooler than the surrounding
photosphere – the lowest layer of the solar atmosphere) and
can last for a few minutes or hours.

A Solar Storm or a Coronal Mass Ejection (CME) as astronomers
call it, is an ejection of highly magnetized particles from
the sun. These particles can travel several million km per
hour and can take about 13 hours to five days to reach Earth.

Earth is surrounded by an immense magnetic field called the
magnetosphere. Generated by powerful, dynamic forces at the
center of Earth, our magnetosphere shields us from erosion of
our atmosphere by the solar wind, erosion and particle
radiation from coronal mass ejections, and cosmic rays from
deep space. Our magnetosphere plays the role of gatekeeper,

repelling this unwanted energy that’s harmful to life on
Earth.

     The Bow Shockoccurs when the magnetosphere of an
     astrophysical object interacts with the nearby flowing
     ambient plasma such as the solar wind. For Earth and
     other magnetized planets, it is the boundary at which
     the speed of the stellar wind abruptly drops as a result
     of its approach to magnetopause.
     The Polar Cuspsare near-zero magnetic field magnitude
     and funnel-shaped areas between field lines that map to
     the dayside and nightside of the magnetopause surface.
     They are the primary regions for direct entry of
     magnetosheath/solar wind plasma into the magnetosphere
     and may create the appearance of beautiful auroras when
     seen from the arctic regions of the Earth.
     Van Allen radiation belt, doughnut-shaped zones of
     highly energetic charged particles trapped at high
     altitudes in Earth’s magnetic field. The belts are most
     intense over the Equator and are effectively absent
     above the poles. The Van Allen radiation belt is a zone
     of energetic charged particles originating from the

solar wind. The particles are captured and held around a
     planet by that planet’s magnetic field. It surrounds
     Earth, containing a nearly impenetrable barrier that
     prevents the fastest, most energetic electrons from
     reaching Earth.

            IMPACT OF GEOMAGNETIC STORMS ON EARTH

ON SPACE WEATHER: Not all solar flares reach Earth, but solar
flares/storms, Solar Energetic Particles (SEPs), high-speed
solar winds, and Coronal Mass Ejections (CMEs) that come close
can impact space weather in near-Earth space and the upper
atmosphere.

ON MAGNETOSPHERE: Coronal Mass Ejections (CMEs) significantly
loaded with matter traveling at millions of miles an hour can
potentially create disturbances in the magnetosphere.
Geomagnetic storms result in intense currents in the
magnetosphere, changes in the radiation belts, and changes in
the ionosphere, including heating the ionosphere and the
thermosphere.

ON SPACE-DEPENDENT SERVICES: Solar storms can hit operations
of space-dependent services like Global Positioning Systems
(GPS), radio, and satellite communications. Aircraft flights,
power grids, and space exploration programs are also
vulnerable to geomagnetic storms.

ON COMMUNICATION: Geomagnetic storms interfere with high-
frequency radio communications that rely on the ionosphere for
propagation.

ON POWER GRIDS, OIL, AND GAS PIPELINES: When the earth is in
the direct path of such solar storms, these magnetized and
charged solar particles will interact with the earth’s
magnetic field and induce strong electric currents on the
earth’s surface that can damage long-distance cables.

ON UNDERSEA INTERNET CABLES: Undersea cables have a higher
risk of failure compared to land cables due to their large
lengths as current is proportional to the area of the loop
formed by the two grounds and the cable.

HEALTH RISKS FOR ASTRONAUTS: Astronauts on spacewalks face
health risks from possible exposure to solar radiation outside
the Earth’s protective atmosphere.

FORMATION OF AURORAS: These storms can create the appearance
of beautiful auroras aurora borealis (the northern lights) and
aurora australis (the southern lights.)

LINK BETWEEN SOLAR STORMS AND ANIMAL BEACHINGS: Researchers
from a cross-section of fields pooled massive data sets to see
if disturbances to the magnetic field around Earth could be
what confuses these sea creatures, known as cetaceans.
CETACEANS are thought to use Earth’s magnetic field to
navigate. Since intense solar storms can disturb the magnetic
field, scientists want to determine whether they could, by
extension, actually interfere with animals’ internal compasses
and lead them astray. However solar storms may not be the
primary cause of animal beaching but the research continues.

LINK BETWEEN SOLAR STORMS AND MIGRATORY BIRDS: Birds possess a
magnetic sense and rely on the Earth’s magnetic field for
orientation during migration. However, the geomagnetic field
can be altered by solar activity at relatively unpredictable
intervals. How birds cope with the temporal geomagnetic

variations caused by solar storms during migration is still
unclear.

CONCERNS WITH GEOMAGNETIC STORMS

The Sun goes through an 11-year cycle – cycles of high
and low sunspots activity. It also has a longer 100-year
cycle. During the last three decades, when the internet
infrastructure was booming, it was a low period. And
very soon, either in this cycle or the next cycle, we
are going towards the peaks of the 100-year cycle. So it
is highly likely that we might see one powerful solar
storm during our lifetime
The rapid development of technology took place in the
last three decades when the Sun was in its period of low
activity and there are very limited studies on whether
our current infrastructure can withstand a powerful
solar storm.

           GEOMAGNETIC STORMS AND INDIA

The countries in the lower latitudes are at a much lower
risk but there is a need for more studies to fully
understand the effects of geomagnetic storms and the
regions of lower latitudes.
Modelled and Simulation Studies to understand how
connectivity will be affected on a country-scale, showed
that the majority of cables connecting India will be
unaffected.
Even under the high-failure scenario, some international

connectivity remains (e.g., India to Singapore, the
     Middle East, etc.). Unlike in China, the key cities of
     Mumbai and Chennai do not lose connectivity even with
     high failures
     Compared to the US, India is less vulnerable, but we
     still need to know more about the strength of solar
     storms and whether a powerful one can affect India.

THE WAY FORWARD

     Shutdown Strategy:‘Shutdown Strategy’ can help minimize
     the connectivity loss during and after a solar storm
     impact. Similar to how we power off power grids, a
     temporary internet shutdown can protect our equipment
     during a solar event and ensure the continuation of
     services.
     Systematic Protocols:
     We need a more systematic protocol for doing this. Both
     NASA and the European Space Agency have probes now that
     can detect a solar storm and can give about 13 hours of
     warning.
     Experts from different fields need to come together to
     design protocols for power companies and internet
     service providers.
     Also, today’s health care system depends on power and
     the internet and we need to have a fallback strategy.
     With the increasing global dependence on satellites for
     almost every activity, there is a need for better space
     weather forecasts and more effective ways to protect
     satellites.

THE CONCLUSION: Current models are capable of predicting a
storm’s time of arrival and its speed. But we are still not
able to predict the storm’s structure or orientation.
Independent solar observations show that solar superstorms
capable of large-scale damage may occur only a few times in a
century. Nevertheless, given their potential to cause large-
scale disruption to our modern society, research and studies

are needed to help us prepare and take steps for reducing
their impact.

MAINS QUESTIONS:

   1. What are geomagnetic storms? What steps are needed to
      prepare for any possible cause of a powerful solar storm
      in the future?
   2. Explain the possible consequences of a powerful solar
      storm on life and property on Earth.

ADDED INFORMATION: 5 categories measure geomagnetic storms
given by National Oceanic and Atmospheric Administration, USA
(NOAA).