Two high-speed, portable GC systems designed for the measurement of non-methane hydrocarbons and PAN: results from the Jungfraujoch High Altitude Observatory

• Published in: Journal of environmental monitoring 2004-03, Vol.6 (3), p.234-234
• Main Authors: Whalley, L K, Lewis, A C, McQuaid, J B, Purvis, R M, Lee, J D, Stemmler, K, Zellweger, C, Ridgeon, P
• Format: Article
• Language: English
• Subjects: Air Pollutants - analysis; Automation; Chromatography, Gas - instrumentation; Environmental Monitoring - instrumentation; Equipment Design; Hydrocarbons - analysis; Peracetic Acid - analogs & derivatives; Peracetic Acid - analysis; Sensitivity and Specificity
• ISSN: 1464-0325; 1464-0333
• DOI: 10.1039/b310022g

Near real-time measurements of light non-methane hydrocarbons (NMHCs) and peroxyacetyl nitrate (PAN) have been performed in the free troposphere using two fast gas chromatography (GC) instruments designed for use on aircraft. A GC-helium ionisation detector (HID) system measured 15 C(2)-C(5) hydrocarbons with 5 min time resolution and a dual channel GC-Electron Capture Detector (ECD) measured PAN with 90 s resolution. Both instruments had low parts per trillion by volume (pptV) detection limits and ran continuously at the remote Jungfraujoch (JFJ) research station in the Swiss Alps (46.55[degree]N, 7.98[degree]E), 3580 m above mean sea level (AMSL), during February/March 2003. Carbon monoxide, ozone, nitrogen oxide and nitrogen dioxide and all odd nitrogen species (NO(y)) were also measured continuously. Hydrocarbons and CO were strongly correlated in all air-masses whilst PAN exhibited both positive and negative correlations with respect to O(3), dependent on age and origin of the air-mass sampled. PAN was found to contribute [similar]20% to the NO(y) sampled on average. The experiment, as well as providing interesting datasets from this remote location, also demonstrated that when optimised, GC techniques have the potential to measure at a time resolution significantly greater than is traditionally considered, with high sensitivity and low uncertainty.