Campaigns
Chemistry of the Antarctic Boundary Layer and the Interface with Snow (CHABLIS)
Overview:
CHABLIS was a major initiative to explore the atmospheric chemistry of the coastal Antarctic boundary layer in far greater detail and for a longer period of time than had been achieved hitherto. Conducted at the Clean Air Sector Laboratory (CASLab) British Antarctic Research Station, Halley, a year-round study of chemical climatology, starting in January 2004, culminated in an intensive summer campaign in January-February 2005 where a comprehensive suite of radicals and other trace species was measured. 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. CHABLIS was funded by a grant from the Natural Environment Research Council (NERC) Antarctic Funding Initiative (AFI).
Key CHABLIS Goals:
- to explore the chemistry of the Antarctic Boundary Layer through a year-round study of chemical climatology culminating in an intensive summer campaign to measure a comprehensive suite of radicals and other trace species;
- to test numerical models of the pristine atmosphere under extreme conditions;
- to extend significantly our ability to interpret ice core data by improving understanding of both the present-day atmosphere and transfer functions.
Molecules Measured:
| Target molecule(s) / measurement | Technique | Detection limit | Data frequency | Duration | Key Goal |
|---|---|---|---|---|---|
| HCHO | Fluorescence | 20 pptv | 5 min | Year-round | 1,3 |
| NMHCs/CH4/DMS | GC | 1/5/100pptv | hourly | Year-round | 1 |
| Halocarbons/RONO2 | Whole air samples | << 1 pptv | weekly | Year-round | 1,2,3 |
| “ ( firn profiles) | “ | “ | monthly | Year-round | 3 |
| Halocarbons/RONO2 | GC/MS | < 1 pptv | hourly | Summer | 1,2 |
| NO/NO2 | Chemiluminescence | 1 pptv | 1 min | Year-round | 1,2,3 |
| PAN | GC/ECD | < 1 pptv | 30 min | Year-round | 1,2,3 |
| NO3 | BL – DOAS | 0.4 pptv | 10 min | Year-round | 1,2 |
| BrO/IO/OIO | BL – DOAS | 1/0.2/0.5 pptv | 10 min | Year-round | 1 |
| OH/HO2 | FAGE (LIF technique) | 1x105/1x106 molec.cm-3 | 2.5 min | Summer | 1 |
| HO2/RO2 | PERCA | 1 pptv | 1 min | Summer | 1 |
| H2O2/CH3OOH | HPLC | 50 pptv | continuous | Summer | 1,3 |
| HONO | Colorimetry | 1-2 pptv | continuous | Year-round | 1,2,3 |
| H2O | Frost point hygrometer | N/A | 10 sec | Year-round | 1 |
| HNO3 | Denuder sampling | < 1 pptv | Day/weekly | Year-round | 1,2,3 |
| O3 | uv absorption | 1 ppbv | 10 sec | Year-round | 1 |
| CO | RGA | 3 ppbv | 10 sec | Year-round | 1,3 |
| CN | Particle counting | 0.02 mm | < 5 sec | Summer | 1 |
| Photolysis rates | Filter radiometers | - | < 5 sec | Year-round | 1,2,3 |
| Snow NO3-, NO2- | IC | < 1 ppb | daily | Year-round | 3 |
| Particulate NO3-, NO2-, Br- | Filter sampling and IC analysis | < 1 pptv | daily/weekly | Year-round | 1,2,3 |
CHABLIS Output
Data are publicly accessible through the British Atmospheric Data Centre
CHABLIS publications
Publications resulting from data collected during the CHABLIS campaign.
CHABLIS participants
The CHABLIS participants, their affiliation at the time, and their role in the project.
