Heavy exposure to the ultraviolet-B radiation can cause cancer. And this cancer-causing radiation’s levels soared to a record high at the top of a volcano in Bolivia, South America in 2003. According to a new study published in the journal Frontiers in Environmental Science, the Ultraviolet index rose to an all-time high of 43.3 on December 29, 2003 at Bolivia’s Licancabur volcano.

Ultraviolet Radiation

Ultraviolet radiation levels in South America frequently surpass 25

The measurements were made using radiation detectors developed for the European Light Dosimeter Network (Eldonet). Nathalie Cabrol, a scientist at SETI Institute in California, and her team had undertaken these instruments to South America as part of their study. They were trying to find out how living beings survive in extreme environments, which could give them clues about the possibility of life on Mars. They deployed these dosimeters on the top of Licancabur volcano (altitude 5,917 meters) and Laguna Blanca (altitude 4,340 meters), which is about six miles away from Licancabur.

The UV index indicates the strength of sun’s ultraviolet radiation. A UV index of around 43 is typical to the radiations on Mars. In the high Andes region, the reading has usually been in mid-20s, said Nathalie Cabrol. Previous findings by Richard McKenzie of New Zealand’s National Institute of Water and Atmospheric Research have shown that the UV index levels in Bolivia, Peru, Chile and Argentina have frequently surpassed 25.

What caused the dramatic surge in ultraviolet radiation in South America?

In the Andes, several factors such as low ozone levels, high elevation and intense tropical sun combine to boost the ultraviolet radiation. But the December 2003 incident saw some unusual combination of factors that significantly reduced the protective ozone levels. Ozone layer in the stratosphere protects us from the harmful UV radiation.

Dosimeters showed that the UV levels were in the 20s just days before reaching an all-time high. Researchers believe that fires burning in the Amazon forest and seasonal thunderstorms over the Andes might have depleted the ozone layer. They believe a large solar flare about two weeks before the sudden surge could also have destroyed some of the ozone layer.

The World Health Organization recommends people not to spend time outside when the UV index hits 12.