Our atmosphere is fragile; yet, it is a lifesaver.

Without it, the Earth would be frozen, lifeless, and pummelled by cosmic radiation.



So it is in our interest to protect it. Now a recently launched satellite is beaming back information that may help.

In orbit since July to monitor ozone, climate change and air quality, the 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.



It has also provided new images of the ozone hole over Antarctica.



With colorful 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.



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.



“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.



Dr DeCola said that the view of the atmosphere from space was essential to understand its composition and chemical dynamics.



Current air quality measurements are limited by less sensitive ground-based instruments.



“You’d need millions, perhaps billions of sensors on the surface to get this kind of information,” said Dr DeCola.



Scientists say Aura will tell them whether the ozone layer is recovering and whether atmospheric treaties such as the Montreal Protocol – designed to reduce ozone-depleting substances in the atmosphere – are working.



Aura monitored both the good stratospheric ozone that shields us from ultraviolet radiation, and the toxic ozone below, in the air we breathe, explained Aura Project Scientist Mark Schoeberl.



“Ozone will attack your lung tissue and make you really sick,” he said. “So we’re interested in air pollution, a component of which is ozone. It’s a critical issue for urban, mega-city environments.”



Car exhausts, chemical solvents and industrial emissions all can lead to bad ozone.



More here.