Voyage of the Giant Ozone Research Balloon

The Balloon's Mission

Giant balloons have been an important research tool for scientists for many years, though most are much better behaved than the one that took a rather unexpected world tour in the summer of 1998. Environment Canada has been launching research balloons into the ozone layer for over 20 years, and even in this age of satellites and hi-tech ground instruments, balloons still have an important role to play in keeping tabs on the ozone layer. Information from balloon-borne instruments enables scientists to improve our understanding of changes in the ozone layer and determine the effectiveness of action taken to reduce ozone-depleting chemicals.

Giant Research Balloon Probes the Ozone Layer

On August 24, 1998, a gigantic research balloon,MANTRA (Middle Atmosphere Nitrogen TRend Assessment), was launched from Vanscoy, a small town near Saskatoon, Saskatchewan, in a co-operative effort by Environment Canada, the Canadian Space Agency, universities and industry, to study the thinning of the earth's ozone layer.

The balloon, made of transparent polyethylene as thin as sandwich wrap, and as tall as a 25-storey building, carried a half-tonne package of instruments up through the ozone layer, reaching an altitude of about 38 km by sunrise. As it rose, the instrument package transmitted data back to the ground station at the Vanscoy base.

By sunset, the balloon had successfully completed its mission. With the data sent back to Environment Canada by telemetry. The balloon was then scheduled to descend, with its payload of instruments floating down on an orange and white parachute and landing near the launch site. Unfortunately, the mechanism to bring the balloon down failed, and the balloon took off on an unscheduled world tour. It drifted eastward - crossing Eastern Canada and heading out over the Atlantic Ocean. It then veered north over Iceland and Northern Russia, and swung back over Scandinavia. It finally landed ten days later, on September 2, on Mariehamn Island in Finland - a journey of about 9,000 km. The payload was later recovered on behalf of Environment Canada by the Finnish Meteorological Institute.

Environment Canada has been launching giant research balloons into the ozone layer for over 20 years. (Although most have been better behaved than the one in 1998). Even in this age of satellites and hi-tech ground instruments, balloons have proven to be an effective and relatively inexpensive method of keeping tabs on the ozone layer.

Data collected during the balloon's flight will be used in computer models that simulate atmospheric chemistry. The results, once known, will help to make our understanding of global ozone depletion more complete. About half of the observed ozone loss in the atmosphere can be definitely attributed to known ozone-depleting industrial chemicals; whether the remaining half is caused by these chemicals or other factors is not yet known.

Giant research balloons can carry heavy payloads of sensitive scientific instruments directly into the ozone layer where they can record the amount of ozone present, and measure CFCs and other ozone-depleting substances. In the August 1998 launch from Saskatoon, the payload contained seven instruments designed by Canadian scientists. Data from these instruments will be compared to measurements taken from past balloon flights, to help track changes in the ozone layer over Canada. The earlier Canadian balloon flights, which began in 1974, were particularly important, as they were carried out before any major ozone depletion was observed.

Canadian balloon measurements have made a significant contribution to improving our understanding of the ozone layer. Environment Canada and York University scientists have used this information to develop and validate computer models to explain changes in the chemistry of the ozone layer. These models contributed to the scientific basis of the Montreal Protocol, an historic international treaty which used scientific research to set limits for the global production of ozone-depleting substances. Balloon measurements are now helping researchers determine the effectiveness of steps taken to reduce these substances.

The 1998 balloon project was a collaborative effort between the Canadian Space Agency, Environment Canada, the Centre for Research in Earth and Space Technology (CRESTech), the University of Toronto, York University, and the University of Denver. Scientific Instrumentation Limited (SIL) of Saskatoon provided payload and launch support.

Balloon research is part of a larger Environment Canada program to understand changes in the ozone layer. Canadian research on the ozone layer began in the 1930s, as an effort to understand the ozone layer's potential benefit to weather forecasting. This research was strengthened in the 1970s, when the threat of ozone depletion was first realised. In 1993, Environment Canada scientists completed the first long-term study conclusively showing that the thinning of the ozone layer has led to an increase in ultraviolet levels at the earth's surface.

Environment Canada has operated the World Ozone Data Centre, under the auspices of the United Nations' World Meteorological Organization, since 1960. These records are essential for understanding long-term change in the ozone layer. As well, Environment Canada scientists developed the Brewer Ozone Spectrophotometer, a state-of-the-art, ground-based scientific instrument. Recognized as the world's most accurate ozone-measuring instrument, it is now in use in more than 35 countries.

For more information:

David Wardle (416) 739-4632
Environment Canada

Tom McElroy (416) 739-4630
Environment Canada

The Green Lane^TM,
Environment Canada's World Wide Web Site.