LOS ANGELES — A NASA spacecraft has begun the first-ever daily tracking of how air pollution moves across the globe, a scientist at NASA's Jet Propulsion Laboratory said Wednesday.

The data from the Aura satellite's four instruments will offer scientists their best look yet at the interplay between pockets of pollution and weather patterns, principal scientist Reinhard Beer said.

Beer said there was no political agenda linked to the project, which comes as President Bush is under international pressure to rejoin efforts laid out in the Kyoto protocol to fight climate change by cutting greenhouse gases. Bush withdrew from the agreement in 2001.

"What people do with the information is not something we can get involved in," Beer said. The data will show how industrial pollutants move through Earth's troposphere, the region that begins at the ground and rises about 11 miles.

The $785 million, five-year mission was expected to help scientists predict where pollution pockets accumulate and how they travel so that "chemical forecasts" can one one day be possible, Beer said.

Launched on July 15, the bus-sized spacecraft makes a complete survey of Earth every 16 days, sending back infrared images of concentrations of five of six major pollutants identified by the U.S. Environmental Protection Agency.

"We are also trying to work backward to pinpoint the source regions," Beer said. "The best we could hope to do is say (a region) is a major source of a certain type of pollution."

All but one of Aura's instruments are functioning normally. Engineers were trying to remove material that was blocking the lens of a device measuring temperature and concentrations of pollutants, a NASA official said.

The science team expects to present its first major conclusions in about a year, Beer said.

Aura also will collect data on "holes" detected in the protective ozone layer at the poles. International treaties ban most uses of ozone-depleting chlorofluorocarbons, but Aura should show whether any earlier damage is being reversed.

Aura now trails Aqua and Terra, its NASA sister ships studying the interaction among Earth's air, water and land.

Four more U.S. and French satellites are expected to be launched over the next several years and take their places between the Aqua and Aura.

Source: Reuters