The Chromatograph for Atmospheric Trace Species (CATS)

The CATS instruments have been in continuous operation at the NOAA baseline observatories since 1999. While the CATS instruments measure the same compounds as their predecessor, the Radiatively Important Trace Species (RITS) instruments; the new gas chromatographs (GCs) also measure several additional trace gases including carbonyl sulfide (COS), halon-1211 (CBrClF2), HCFC-22 (CHClF2), methyl chloride (CH3Cl), and methyl bromide (CH3Br). The CATS GCs are custom built instruments with four separate channels. Each channel is comprised of a pair of separation columns, flow controllers, an air selection valve, and an electron capture detector. More information on the CMDL/HATS in situ programs and chromatography techniques can be found at this link.


CATS Data

Engineering Data

Chromatograms - Display Recent Chromatograms

Mixing Ratios - Preliminary and finalized data
Calibration Tanks - Current and past calibration tanks

CATS Documentation

CATS Data Acquisition Manual
Channel 4 plumbing
Removing/Installing Channel 4 Trap
Setting Sample Flows
Running a cal3 tank

Description of in situ program at CMDL
List of observatories with CMDL in situ programs


Contacts:

Geoff.Dutton@noaa.gov
Thayne.M.Thompson@noaa.gov
James.W.Elkins@noaa.gov