SPACE

The big picture

NASA plans satellites to track the climate

DIANE BRADY October 1 1990
SPACE

The big picture

NASA plans satellites to track the climate

DIANE BRADY October 1 1990

The big picture

SPACE

NASA plans satellites to track the climate

As experts increasingly recognize the worldwide nature of pollution and other environmental hazards, many scientists say that they have become convinced that the problem must be studied on a global basis. As a result, the Washington-based National Aeronautics and Space Administration is currently developing six 15-ton satellites, which would be the largest unmanned spacecraft ever launched by the United States, in order to study climate patterns and environmental change from space. Called the Earth Observing System (EOS), the 15-year project, estimated to cost $35 billion, will gather data continuously on such diverse phenomena as polar ice, tropical storms and atmospheric pollutants, beginning in 1998. Scientists say that they hope the data will lead to imporTyphoon Bill: seeking answers

tant new discoveries about subjects ranging from tropical rain-forest destruction to Prairie wheat yields. Said James Drummond, a University of Toronto physicist who is designing an instrument for the project: “We need an integrated set of measurements to understand the continuity of climate change.”

The elaborate EOS satellites will collect enough information on the Earth’s environment every day to fill the memories of 50,000 personal computers. Advocates of the project also maintain that the data will vastly improve the accuracy of assessing environmental problems, leading to possible scientific solutions. Since NASA proposed the project in 1988, hundreds of scientists from more than 15 countries, including Canada, have begun designing equipment that may eventually be used on the satellites. Said Gordon McBean, a University of British Columbia climatologist who is regarded as a world authority on climate change: “We need a massive global experiment like EOS to deal with the Earth as a system.”

But other scientists claim that megaprojects like EOS $ consume too much research z money and talent. Andrew to nature’s complex forces Lacis, a New York City-based

climatologist with the Goddard Institute for Space Studies, said that an entire scientific discipline can suffer when a megaproject fails to perform according to expectations. He noted that NASA’s $ 1.85-billion Hubble Space Telescope, launched in April, will take three more years to achieve its design potential because the main mirror has failed to focus accurately the light that strikes it from outer space. Said Lacis; “Megaprojects have a way of slipping and being delayed and going wrong.”

So far, the scientific community has supported NASA’s proposal to have EOS in operation in eight years. If that happens, there will eventually be two satellites always in north-south orbit around the Earth at an altitude of nearly 440 miles. Each spacecraft will pass near the poles once a day, and some of its instruments will gather data across a 700-mile-wide swath of the Earth’s surface. The first satellite will probably monitor changes in vegetation, ice cover and precipitation, while the second, scheduled for launching before the year 2000, would measure such natural phenomena as continental drift, atmospheric ozone levels, wind speeds and temperatures.

Canadian scientists have eagerly joined the competition to design equipment that could be used on board the satellites or as ground-based support. The U of T’s Drummond is developing an instrument to measure carbon monoxide and methane, two atmospheric gases that may be important factors in climate change. Drummond said that the instrument is among 20 being designed for use on the first satellite. He added that NASA plans to select 12 to 16 devices by the end of this month. Meanwhile, the Ottawa-based Canada Centre for Remote Sensing, a branch of Energy, Mines and Resources, is leading several global-change studies that incorporate and interpret the data collected from EOS. Said Barry Goodison, coordinator of space programs at Environment Canada’s Canadian Climate Centre, and one of 35 Canadian scientists involved in the studies; “We see this as an opportunity to push Canada into more Earth observation research.”

Many scientists say that EOS could lead to international action on global pollution. Ellsworth LeDrew, a University of Waterloo, Ont., geography professor who is involved in the Canada Climate Centre’s studies, said that scientists must provide a clearer understanding of the extent and causes of environmental damage before governments can be expected to take co-ordinated action. Said LeDrew; “We have to view the globe as a single unit and develop strategies that treat it as one system.” Despite concerns about EOS, which shares the name of the Greek goddess of the dawn, most scientists involved have expressed excitement about the possibility of observing weather patterns as a global system. Some even believe the program could change mankind’s approach to solving environmental problems. And that possibility may make EOS a winner with both politicians and the public.

DIANE BRADY

WILLIAM LOWTHER