What if data became useless?

In the first half of 2020, a global pandemic caused over a million deaths (at the time of writing this article), and a major economic slowdown due to a complete shutdown of the economic activity in the largest countries for several weeks. The statistical risk of such pandemic was known: Covid-19 was a new virus so its emergence could not be anticipated, yet the probability that an influenza strain would kill more than 2 million people on the planet was estimated at 2% per year approximately, i.e. once every 50 years¹. Action plans had existed for decades in most countries, except for one detail: due to globalization, the virus would spread faster than anticipated 20 or 30 years earlier, and the consequences on the healthcare sector or the economy would largely exceed the anticipations.

Statistically, many threats have a likelihood in the same ballpark as a global pandemic and with potential economic consequences at least as great. In June 2020, Deutsche Bank analysts proposed a list of events including a world war, a volcanic eruption equivalent to that of Tambora in 1815 – 1000x more powerful than the “small” Icelandic eruption which paralyzed much of the European airspace in 2010 - and finally, a massive solar flare or more precisely a coronal mass ejection (CME), i.e. the projection of a large volume of magnetized particles from the solar corona towards Earth.

Of this last risk, most people only have a very vague idea. Those who are aware of the probability (1.06% per year²) likely understand the consequences for our society in an era when electricity, wifi and data have become resources almost as vital as water and air.

The reason why this threat is ignored is that, despite 11-year cycles in solar activity, Earth has, against all odds, been spared major eruptions in the recent past. At the peak of each solar cycle, the sun emits nearly 3 EMCs of variable power per day vs. 1 per week at the minimum of the solar cycle. In that context, the fact that EMCs have “missed” Earth for so long seems like a statistical anomaly.

The largest documented EMC reached Earth in 1859: at the time, telegraph poles caught fire, telegraph operators were electrocuted, and the aurora borealis could be observed at tropical latitudes. 140 years later, in 1989, a power outage plunging Quebec City into darkness for nearly 12 hours was associated with a much smaller phenomenon. And in July 2012, Earth avoided the path of a massive CME by just a few months.

In the collective imagination, this phenomenon is associated with solar flares or prominences that we can see representations of on television. While EMCs often occur at the same time as solar flares, it is not certain that the two phenomena are necessarily linked. The EMC phenomenon is not fully understood but it seems to occur because of a momentary imbalance of the solar corona’s magnetic field. The imbalance comes from the paradox between the tendency of very hot bodies (such as the Sun) to expand and the tendency of very massive bodies (such as the Sun too) to contract due to the strong gravitational attraction. The balance of the corona’s magnetic field is only restored after the expulsion of highly magnetic particles via EMCs. When the projection is directed towards the Earth, the particles can take between 13 hours and 86 days to reach our planet, on average 3.5 days.

On August 31, 2012, an EMC sent particles into space at a speed of 1,500 km per second. This EMC avoided Earth's trajectory but re-entered its magnetic field, causing auroras on Monday, September 3. Above is a photo combining the 304 and 171 Angstrom wavelengths. Credit: NASA/GSFC/SDO

Earth's magnetic field is our main shield, which prevents most of the solar "winds" from reaching our atmosphere. The regions above magnetic poles are usually the only entry points because the particles typically align and follow magnetic field “lines”, which extend from Earth’s core out into space and cross the atmosphere above the magnetic poles. When the highly magnetized particles manage to reach the gases in the atmosphere, they excite the gases and trigger a luminous emission akin to what happens in a neon.

This reaction is the origin of auroras in polar regions. Those who have witnessed these auroras know that several colors are visible, and this corresponds to concentrations of different gases at different altitudes in the atmosphere.

In the event of a massive EMC, the earth's magnetic field may be too weak to repel the magnetic field of particles arriving from the sun: imagine two magnets, the weaker one will always align with the magnetic field of the stronger one. This is how these particles can enter the atmosphere at any latitude as shown in this animation (1859’s EMC at 1’25”). This is what explains why auroras were observed from Cuba or Puerto Rico in 1859.

For our modern society, an event of such magnitude could have cataclysmic consequences because its effects would not be limited to a light display in the sky.

Even before reaching Earth, these particles can wreak havoc in space, particularly on the electrical circuits of satellites, causing major disruptions to our communications systems. The same goes for GPS navigation systems. Most satellites have protection mechanisms to prevent the electrical circuits from being completely destroyed, but the particles would interfere with the signals between the Earth and these satellites, making them useless.

On Earth, compasses would be inaccurate for the duration of the storm, interfering with the few navigation systems that are not dependent on the failed satellite network. The particles would also interfere with radio waves. All air traffic and much maritime traffic should be halted. Due to the magnetic field of the solar particles, an electric current would be generated in all exposed conductive materials. Thus, all high voltage lines and transformers would be at risk of overvoltage which could destroy them if they are not preventively stopped or at least significantly throttled. The entire planet could therefore be without electricity for several days because it would be a matter of shutting down entire electrical infrastructures and then restarting them in a secure manner. This means no light, no refrigerators, no means of payment and no mobile network or internet. And obviously no data transfers. So no banking system, no water (water distribution systems in modern cities are electronically controlled) and certainly a human disaster in hospitals without water, without electricity and without access to digital records. Smaller electrical appliances should not be exposed to significant damage, but there would be no electricity to power them or recharge them.

One should also consider that the risk of a world war – which we touched on at the beginning of this article - is not exclusive of the EMC risk. History has shown that it could even increase in case of a small EMC: in 1967, an EMC almost triggered a nuclear war as the magnetic field of solar particles interfered with US ballistic radars, which the US military interpreted as intentional jamming of the Soviet military. Counter-attack nuclear bombers were almost launched by the United States. Fortunately these days, solar meteorologists can identify these phenomena as they leave the solar corona, and gvie a heads-up of about 3 days to protect satellites and electrical infrastructure... with the hope that they will restart without too much difficulties.