The world's highest levels of surface UV

Area of Science:

• Atmospheric Science
• Ozone Layer Research
• Solar Radiation Studies

Background:

• The Atacama Desert is recognized for potentially having the highest surface ultraviolet (UV) radiation globally.
• Key factors contributing to high UV levels include high altitude, clear skies, and a low total ozone column.

Purpose of the Study:

• To measure and detect peak surface UV levels in Chile's Atacama Desert.
• To compare UV index measurements between different high-altitude locations.

Main Methods:

• Conducted ground-based spectral measurements in January 2013 at Chajnantor Plateau (5100 m) and Paranal Observatory (2635 m).
• Utilized spectral measurements from Izaña Observatory (2367 m) from June 2005 for comparative analysis.
• Calculated the UV index based on spectral measurements.

Main Results:

• The UV index reached a peak of 20 on the Chajnantor Plateau under broken cloud conditions.
• A peak UV index of 16 was recorded at the Paranal Observatory under cloudless conditions.
• Southern hemisphere sites are expected to have higher peak UV levels than northern hemisphere counterparts due to various environmental factors.

Conclusions:

• The Atacama Desert exhibits exceptionally high surface UV radiation levels.
• Altitude, ozone concentration, and atmospheric conditions significantly influence UV index.
• Further research is needed to fully understand the geographical variations in UV radiation.