Observational data are the foundation upon which our knowledge of atmospheric composition, trends and processes are based. These data also provide the drivers for continued improvement and development of Earth system models. ACOM has a long heritage of making high quality measurements of atmospheric composition, in collaboration with members of the wider atmospheric chemistry community. Measurements are made in situ from aircraft or at ground sites, or via remote sensing techniques involving satellite- and ground-based instrumentation.

In Situ Observations

In situ observations have long been a centerpiece of ACOM activities. This work is done in partnership with NCAR EOL, and in collaboration with and in support of the activities of the wider atmospheric chemistry research community. Major ACOM activities include:

1. Deployment of community-requestable instruments, including the HAIS (HIAPER Airborne Instrumentation Solicitation) instrument suite;
2. Deployment of additional instrumentation, in community field project settings;
3. Use of laboratory-based chambers to conduct collaborative process-level gas-phase and aerosol research;

Research groups involved:

• Atmospheric Radiation Investigations and Measurements – Sam Hall
• Community Airborne Research Instrumentation - Frank Flocke, Andy Weinheimer
• VOC Measurements – Eric Apel
• Chamber Studies - Xuan Zhang
• Laboratory Kinetics - Geoff Tyndall
• Engineering - Steve Shertz

For a list of community-requestable instrumentation, and request procedures, see http://www2.acom.ucar.edu/observations/community-requestable-instrumentation

For a list of field projects in which ACOM has participated, and access to available data from these campaigns, see http://www2.acom.ucar.edu/campaigns

Remote Sensing

ACOM has long made significant contributions to the determination of atmospheric composition via remote sensing methodologies. This includes design and deployment of satellite instrumentation, deployment of ground-based instrumentation, satellite data retrieval, provision of datasets to the community and data analysis. Currently, The Satellite and Remote Sensing section of ACOM includes several groups with expertise in satellite and ground-based remote sensing measurements of atmospheric composition, clouds and aerosols, and their combination with chemical models.

Research groups involved:

• Measurements Of Pollution In The Troposphere (MOPITT) - Helen Worden
• Optical Techniques - James Hannigan
• UTLS Studies - Laura Pan