Development and Application of a Cryogenic Preconcentration System for Halogenated Greenhouse Gas Measurements in Korea

East Asia represents a major source region of greenhouse gas emissions associated with rapid industrialization and increasing energy demand. Among these emissions, halogenated synthetic greenhouse gases such as HFCs and PFCs, which have been widely used as substitutes following international regulations for ozone layer protection, are characterized by high global warming potentials (GWPs).

In South Korea, halogenated greenhouse gases have been monitored at the Gosan station on Jeju Island using the MEDUSA system of the AGAGE network.  However, the expansion of observational coverage and the establishment of measurement capabilities remain essential to better characterize regional emission signals.  In this study, a cryogenic preconcentration and analysis capability for halogenated greenhouse gases (NIMS-preconcentrator) was developed and and evaluate its capability for monitoring halogenated greenhouse gases.

The analytical setup includes a cryogenic thermal desorption (TD) unit and a pre-concentration trap capable of reaching temperatures down to −170 °C, integrated with an automated valve control module and gas chromatography–mass spectrometry (GC–MS). Measurements were conducted using an offline canister-based sampling approach. Analysis of ambient air samples collected at Anmyeondo (GAW station) resolved about ten halogenated greenhouse gas species, including HFC-134a, HFC-125, and legacy chlorofluorocarbons such as CFC-11 and CFC-12. Concentrations were evaluated using calibration standards, and ongoing performance assessment is conducted using laboratory working standards employed at the Gosan AGAGE station.

This study aims to establish a new measurement capability for halogenated greenhouse gases and to assess its consistency with international observation. Continued operation of this system will support the accumulation of long-term observational datasets and facilitate regional-scale analysis and inter-comparison of high-GWP halogenated greenhouse gases in Northeast Asia.