During the 10th – 13th of December 2012 (the week following AGU), the 4th Atmospheric Chemistry Mechanisms (ACM) Conference (100-150 participants) was held in Davis, California, USA. The conference was spiced with delicious food, high quality talks and state-of-the-art atmospheric chemistry science, and it is definitely recommendable. Every session was concluded with a general discussion concerning the topic of the session, which gives the impression that this is more like a workshop than an actual conference. The hottest topic seemed to be Criegee Intermediates and their potentially important atmospheric reactions with SO2 to form sulphuric acid. The meeting included a special session on amines, which both counted engineering talks on how to capture CO2 using amines (this is known as CCS: carbon capture and storage) and the following emission of amines to the atmosphere due to this process and potential effects, together with more traditional talks about atmospheric amine chemistry and amines role in atmospheric aerosol formation and growth.
There was a session on isoprene (which is the most biogenically emitted volatile organic compound (VOC) with 40% of the total global emission) and HOx (=OH + HO2) measurements and the interference in these. The chemistry of isoprene has been well debated in previous years and this session also included discussion on the sources, sinks and degradation (e.g. to alkylperoxy radicals and epoxides) of isoprene and its degradation products fate in the atmosphere. Five or so years ago, recycling of OH through isoprene reactions was a hot topic. However, it seems that this source of OH is not thought to be so significant any more.
The meeting also counted sessions on gas phase precursors to SOA (secondary organic aerosol) formation including a discussion on how important the explicity of the chemical mechanism has to be in order to get something reasonable. Modellers’ favourite tools, chemical mechanism generators, were also covered with presentations on the probably most used atmospheric chemical mechanism MCM (Master Chemical Mechanism) and what we can expect of its new version (MCM 4.0). This session also included presentations on the mechanism developments of SAPRC and BOREAM (which are near-explicit mechanisms like MCM) and GECKO-A (which is a explicit mechanism). New developments in theory and experiments, future legislative drivers, investigations in Titan’s atmosphere, geoengineering and bio-energy were also presented and discussed during the meeting.
Participants from HY: Taina Yli-Juuti (atm division), Theo Kurtén (chemistry department) and Ditte Mogensen (atm division).