1. Scope -is the work directly or implicitly related to atmospheric composition? 2. Novelty -does the work provide a) a general and/or broader relevance (e.g. not a pure local study), b) new results or methods, and c) does it add significantly to the knowledge of atmospheric composition and its impacts?3. Quality -does the work contain high quality a) atmospheric observations, b) process studies, c) modeling exercises or d) data analysis?Will your paper be within the scope of Atmospheric Environment?We try to be flexible with novel scientific articles on issues of atmospheric composition even, if they are not directly related to atmospheric measurements (e.g. wind tunnel studies, dynamometer studies, remote sensing retrieval, etc). However, we are still cautious of purely mathematical derivations, preliminary results or insignificant case and local studies. The authors should make sure that the articles contain substantial contributions to the science of atmospheric composition before sending them for review.

Interaction with ozone transfers its anomalous (non-mass-dependent) 17O enrichment to atmospheric nitrogen oxides and nitrate. The 17O anomaly (Delta17O) in nitrate can be used to identify atmospheric nitrate inputs into terrestrial and aquatic environments as well as to study the role of ozone in the atmosphere's reactive nitrogen cycle. We report here on an online method for analysis of the 17O anomaly, using a strain of denitrifiers to convert nitrate to N2O, which decomposes quantitatively to N2 and O2 in a gold furnace at 800 degrees C, followed by gas chromatographic separation and isotope analysis of O2. This method requires approximately 50 nmol of nitrate, 2-3 orders of magnitude less than previous offline thermal decomposition methods to achieve a similar analytical precision of 0.5 per thousand for Delta17O. There is no significant memory effect, but calibration via nitrate or N2O reference materials is required for scale normalization. The N2O decomposition method is shown to be well-suited for nitrate analysis in freshwater and seawater samples from various environments.

Throughout the year 2001, aerosol samples were collected continuously for 10 to 15 days at the French Antarctic Station Dumont d'Urville (DDU) (66 • 40 S, l40 • 01 E, 40 m above mean sea level). The nitrogen and oxygen isotopic ratios of particulate nitrate at DDU exhibit seasonal variations that are among the most extreme observed for nitrate on Earth. In association with concentration measurements, the isotope ratios delineate four distinct periods, broadly consistent with previous stud