John Gormley
Question:71 Mr. Gormley asked the Minister for Public Enterprise if her Department will supply Deputy Gormley with the latest measurements for stratospheric ozone over Ireland; and if she will make a statement on the matter. [18953/98]
Written Answers. - Ozone Layer.
Stratospheric ozone concentrations over Ireland have been monitored continuously since 1993 at Met Éireann's weather station Valentia Observatory in Caherciveen, County Kerry. In addition, during the winter months, special balloons are launched from the observatory to measure the vertical variation of ozone.
In addition to Met Éireann's input, other sources of funding for this ozone monitoring have included the EU STRIDE programme and the Department of the Environment and Local Government. These programmes involve partners in Ireland and abroad, notably the chemistry department of UCD.
The phenomena involved in ozone depletion will be investigated in great detail during the coming winter in the Third European Stratospheric Ozone Experiment — THESOE. Valentia Observatory will play a significant role in ozone monitoring for THESOE. There is a clear link between increased Ultra Violet-B Uv-B radiation levels and ozone depletion. UV-B levels are monitored continuously at sites in Donegal, Galway and Kerry.
Since 1984 to date, there has been clear evidence of a 7 per cent thinning of the ozone layer over mid-latitudes. Extremely low temperatures at the North Pole are required for springtime ozone depletion due to chloroflurocarbons — CFCs — and other ozone depleting chemicals. Such conditions have existed in recent winters — 1994-97 — leading to below average ozone values over Ireland and the rest of northern Europe. Conditions in the 1997-98 winter were milder and so current ozone values are closer to long-term averages. However, the overall trend of stratospheric ozone concentration over Europe is downward.
Data for Valentia Observatory
|
Mean Ozone Value — September 1998 |
295 Dobson Units (DU) |
|
Long-term mean value for September |
300.5 DU |
|
Long-term Annual Mean |
330 DU |
|
Record Low ozone value 25th November 1996 |
222 DU |