Rare Solar Blasts Can Damage Earth’s Ozone Layer and Increase Radiation


Solar storms, like the one that caused vibrant auroras this past May, are beautiful but can be dangerous.

Scientists are studying “solar particle events” (SPEs), which are powerful bursts of protons from the sun that can cause significant damage to Earth’s ozone layer and increase harmful ultraviolet (UV) radiation.

The Protective Role of Earth’s Magnetic Field

Earth’s magnetic field acts as a shield, protecting us from solar radiation.

This field, which behaves like a giant bar magnet, has changed over time.

For example, the north magnetic pole has moved about 40 kilometers per year across northern Canada over the last century, and the field has weakened by 6%.

What Happens During a Solar Particle Event?

The sun constantly emits a stream of electrons and protons, known as the “solar wind.”

Occasionally, it releases intense bursts of protons in SPEs, often linked to solar flares.

These protons can penetrate deeper into Earth’s atmosphere, causing excited gas molecules to emit X-rays, which are invisible to the naked eye.

Historical Extreme Solar Particle Events

Records show that extreme SPEs occur roughly every thousand years, with one of the most recent events happening around 993 AD.

These events can deplete the ozone layer, which protects us from harmful UV radiation.

Increased UV levels can damage DNA and increase the risk of skin cancer.

The Impact of a Weak Magnetic Field

If an SPE hits Earth when the magnetic field is weak, the damage can be much worse.

A weak magnetic field allows more radiation to reach the surface, depleting ozone for up to six years and increasing UV levels by 25%.

This could significantly boost the rate of DNA damage by up to 50%.

Historical Connections

Periods of weak magnetic fields have coincided with significant evolutionary changes.

For example, 42,000 years ago, a weak magnetic field period saw the extinction of the last Neanderthals and large Australian marsupials.

Similarly, the origin of multicellular animals and the rapid evolution during the Cambrian Explosion might be linked to geomagnetic changes and increased UV radiation.


Understanding the role of solar activity and Earth’s magnetic field is crucial in uncovering the history of life on our planet.

While we still have much to learn, these findings highlight the delicate balance that protects life on Earth from the sun’s powerful forces.