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From VOA Learning English, this is the Education Report.
Students at St. Louis University have launched weather balloons into the sky above the city of St. Louis, Missouri. The United States space agency, NASA, is paying for the project to measure ozone gas. It is part of a study to learn more about air pollution and our climate.
The students are getting the opportunity to carry out a real scientific experiment. They used a laptop computer and a radio receiver outside the St. Louis Science Center to communicate with data-gathering devices on the balloon.
Before launch, the students tested all the instruments, and attached them to the weather balloon filled with helium. Gary Morris is a professor at Valparaiso University in Indiana. He is the lead trainer for the nationwide study. The professor says NASA wants more information on ozone because of how it affects our atmosphere. High above the Earth, in the stratosphere, the ozone layer keeps harmful ultraviolet radiation from reaching the ground. But, in the lower atmosphere, emissions from cars and other sources like petrochemical plants form ozone pollution and smog. They cause unhealthy air conditions that affect breathing.
Jack Fishman leads the ozone study at St. Louis University. He says new requirements that decrease pollution have lowered ozone levels in American cities. But he notes that pollution in remote areas continues to increase. He blames industrial activity in East Asia for that pollution. Jack Fishman says polluted air is being blown across the Pacific by air currents in the upper atmosphere. He says ozone pollution has slowed the growth of farm crops and forests.