Water vapour has a complex spectrum and absorbs from the microwave to the near-UV where it dissociates. There is limited knowledge of the absorption features in the near-UV, and there is a large disagreement for the available models and experiments. We created a new ab initio model that is in good agreement with observation at 363 nm. At lower wavelengths, our calculations suggest that the latest experiments overestimate absorption. This has implications for trace gas retrievals in the near-UV.

In this study we identify pyrolysis gases from prescribed burns conducted in pine forests using a manual extraction device. Captured gases were analyzed in the laboratory using infrared absorption spectroscopy. Results show that emission ratios relative to CO for ethene and acetylene were significantly greater than in previous fire studies, suggesting the sampling device was able to collect gases generated prior to ignition; this is corroborated by novel detections of five compounds via FTIR.

We report five species (naphthalene, methyl nitrite, allene, acrolein and acetaldehyde) that were detected in biomass burning fires that had been seen before in burn studies, but are reported for the first time when using infrared spectroscopy for detection.