Ozone and UV

NILU measures the development of the ozone layer in the atmosphere from Blindern, in Oslo, and at Andøya, outside of Tromsø. Ozone is also measured over Ny-Ålesund in the spring and fall to observe losses in the arctic ozone layer.

Polar stratospheric clouds over Kjeller and Oslo. Photo: NILU

The ozone layer is located in the stratosphere at altitudes ranging from about 15-35 km, depending on the latitude. Nearly 90% of all ozone in the atmosphere is found in this area, while the remaining 10% is found in the troposphere.

Stratospheric ozone is essential for life on Earth. Ozone absorbs all light with a wavelength shorter than 290 nm (nanometres) and much of the light between 290 and 320 nm, known as UV-B. This is the radiation that burns our skin, which is why sunscreens are primarily designed to protect us against it. The ozone layer protects the Earth from large, harmful doses of UV radiation. If the ozone layer is reduced by 1%, ground-level radiation increases by 1.0 to 1.2%.