Scientists at The Netherlands KNMI in cooperation with ESA are tracking an
ozone mini hole opening over the North Atlantic and heading for Europe.
The KNMI scientists predict that the mini hole will see ozone levels fall
to 60-70% of the seasonal average as it sweeps from Greenland to southern
Scandinavia over the next few days. KNMI’s unique GOME Fast Delivery
Service, developed under the ESA Data User Programme, harnesses near real
time processing of data from the GOME instrument aboard ERS-2. The
scientists are able to monitor the loss of ozone in the atmosphere, and
watch the mini hole as it moves and deepens hour by hour, in real time.

Ozone helps to shield the earth’s surface – and skiers or sunbathers –
from the harmful ultraviolet light rays of the sun. This mini ozone hole
does not present a significant threat, though. According to Ankie Piters
at KNMI “At this time of the year at our latitudes, the sun does not
rise high enough above the horizon to deliver a significant amount of
harmful ultra-violet light, but low ozone events over Europe are still of
great interest. They seem to be caused mainly by unusual air currents in
the atmosphere, not by chemical breakdown of ozone, which is what you see
in the development of the Antarctic ozone hole.” The significance of this
event is that the measurements of the GOME instrument processed in near
real-time enable detailed monitoring and analysis of this phenomenon. For
the first time scientists are able to forecast such an event.

“GOME is a spectrometer which scans the atmosphere below the flight path
of the ERS-2 satellite,” explains ESA’s Claus Zehner. GOME gathers
sunlight backscattered by the atmosphere and reflected by the earth’s
surface and analyses its spectrum from ultra-violet to infra-red.
Different chemical “species” absorb specific wavelengths of light, so
their presence shows up as absorption lines in the measured GOME spectra.

Europe is already preparing the next generation of satellite instruments
to improve the monitoring of ozone and other key chemicals in the
atmosphere.

The SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric
CartograpHY) instrument onboard ESA’s environmental satellite Envisat will
continue the GOME series of ozone measurements soon. And ESA and the
European Organisation for the Exploitation of meteorological Satellites,
EUMETSAT, are preparing a series of three satellites (Metop) which will
carry follow-on GOME instruments and will guarantee at least ten years
continued monitoring of ozone from space from 2003 onwards.

Images and more at:
http://www.esa.int/export/esaCP/ESAHFRQQSTC_index_0.html

Further information:

Claus Zehner

ESA/ESRIN

tel: 00 39 06 94 180 544

Fax: 00 39 06 941 80 552

claus.zehner@esa.int