'Eye In The Sky' Watches Over Air

[zavvy]

<b>'Eye In The Sky' Watches Over Air </b><br /><br />LINK<br /><br />The air around us seems abundant from Earth. But from space, our endless blue sky is only a thin shield around a massive planet. <br /><br />Our atmosphere is fragile; yet, it is a lifesaver. <br /><br />Without it, the Earth would be frozen, lifeless, and pummelled by cosmic radiation. <br /><br />So it is in our interest to protect it. Now a recently launched satellite is beaming back information that may help. <br /><br />In orbit since July to monitor ozone, climate change and air quality, the US space agency's (Nasa) Aura satellite has already produced the first direct measurements of lower atmospheric - tropospheric - ozone from space, including chemicals that are a precursor to "bad ozone" at ground level, and those that form high levels of ozone over the tropics. <br /><br />It has also provided new images of the ozone hole over Antarctica. <br /><br />With colourful high-resolution images, and a bit of animation, scientists can watch chemical reactions in the atmosphere daily, such as the conversion of safe chlorine to the dangerous form that destroys stratospheric ozone. <br /><br />It is an unprecedented look at the health of the swirling mix of trace gases that protect life on Earth, and also the chemical reactions that threaten it. <br /><br />Treaty checks <br /><br />"Our results are exceeding our wildest expectations," said Phil DeCola, Nasa's Aura Program Scientist, who reported at the Fall Meeting of the American Geophysical Union (AGU) in San Francisco. <br /><br />Dr DeCola said that the view of the atmosphere from space was essential to understand its composition and chemical dynamics. <br /><br />Current air quality measurements are limited by less sensitive ground-based instruments. <br /><br />"You'd need millions, perhaps billions of sensors on the surface to get this kind of information," said Dr DeCola. <br /><br />Scien