image: Changes in NO2 emitted to the atmosphere and changes in how fast it leaves the atmosphere (the lifetime). The lifetime varies in space (shown here) and time (shown in the paper). This material relates to a paper that appeared in the 8 Nov. issue of Science, published by AAAS. The paper, by J.L. Laughner at University of California, Berkeley in Berkeley, CA, and colleagues was titled, "Direct observation of changing NOx lifetime in North American cities." view more
Credit: [Credit: Joshua L. Laughner and Ronald C. Cohen]