Press release archive: 2011

Record-breaking Arctic ozone loss anticipated

30.3.2011 13:26

Exceptionally cold temperatures in the ozone layer over the Arctic region together with high concentrations of ozone-depleting substances in the atmosphere are leading to a record loss of ozone over northern regions.

Photo: Antonin Halas

Photo: Antonin Halas

It is predicted that the situation will continue at least until early April. Unusually cold temperatures at an altitude of 20 kilometres in the stratosphere together with continually high concentrations of ozone-depleting substances are leading to record-breaking ozone depletion over northern regions.

According to calculations made, climate change will raise temperatures in the lower layers of the atmosphere while the upper atmosphere is getting colder. At the same time, the ozone layer over the Arctic will also become colder. In the Arctic regions, this can mean circumstances that accelerate ozone depletion during the next decades.

The amount of UV radiation increases

The area of low ozone concentration affects the amount of UV radiation reaching the earth’s surface. The Finnish Meteorological Institute points out that, according to the guidelines issued by the World Health Organization (WHO), people should protect themselves from the sun when the UV index exceeds 3. In other words, solar UV radiation should be taken into account when spending time outdoors next weekend. Especially the eyes should be protected because they receive UV radiation both directly from the sun and reflected by the snow.

The Finnish Meteorological Institute constantly monitors UV radiation levels and publishes UV index values daily on the website and, whenever necessary, together with weather forecasts. The UV index, or UVI, uses one figure to show the intensity of harmful UV radiation. The Finnish Meteorological Institute also makes short-term UV forecasts in order to draw people’s attention to the health risks of UV radiation. The skin and eyes should be protected when the UV index reaches or exceeds 3. On average, such readings are obtained in Southern Finland from the beginning of May to the end of August and in Northern Finland from the beginning of June to mid-August. This year the need for protection has surfaced about one month earlier than normally.

Additional information:

UV index forecast:
Leif Backman, Head of Group, tel. +358 50 405 0752,

UV radiation:
Tapani Koskela, Research Scientist, tel. +358 50 584 9054,