Chemistry of the Antarctic Boundary Layer and the Interface with Snow (CHABLIS) is a Natural Environment Research Council (NERC) and Antarctic Funding Initiative (AFI) funded project, aimed at studying the chemistry of the Antarctic Boundary Layer in greater detail, and for a longer duration, than has previously been attempted.

Fieldwork was carried out at the new Clean Air Sector Laboratory (CASLab) at Halley station . The team from UK universities and the British Antarctic Survey brought to the project a suite of state-of-the-art instruments and models and a track record of successfully running major campaigns together in remote locations. The field campaign started during the austral summer in January 2004 and continued throughout the winter culminating with an intensive study during the summer of 04/05.
Major foci for CHABLIS included detailed studies of seasonal oxidant chemistry, annual variation in the boundary layer NOy budget and elucidating air/snow transfer processes.
The dataset includes mixing ratios (Ozone, CO, HCHO, NO2, and HONO), accumulation and isotope (Na, K, Mg, Ca, F, CH4, Cl, and NO3) concentrations of snow, and meteorological measurements (relative humidity, visibility, dew point, wind speed, and wind direction). Access to this dataset is now public.