The measurement of atmospheric CO₂ at KMA GAW regional stations, its characteristics, and comparisons with other East Asian sites

Abstract

To understand the carbon cycle at policy-relevant spatial scales, a high density of high-quality CO 2 measurement sites is needed. In 2012, the Korea Meteorological Administration (KMA) installed CO 2 monitoring systems at Anmyeondo (AMY) in the west, Jejudo Gosan Suwolbong (JGS) in the southwest, and Ulleungdo (ULD) in the east of South Korea. Three stations were instrumented with identical greenhouse gas measurement systems based on cavity ring-down spectroscopy (CRDS) and a new drying system developed by KMA and the Korea Research Institute of Standards and Science (KRISS). This drying system is suitable in humid areas; water vapor measured using CRDS in ambient air was 0.001 % to 0.004 % across the stations. Measurement uncertainties expressed by the quadrature sum of the uncertainties from the drying system, scale propagations, repeatability, and reproducibility were ∼ 0.11 ppm from all KMA stations in the 68 % confidence interval. Average monthly CO 2 enhancements above the local background at each station were 4.3 ± 3.3 ppm at AMY, 1.7 ± 1.3 ppm at JGS, and 1 ± 1.9 ppm (1σ ) at ULD, respectively, during 2012 to 2016. At AMY station, located between China and South Korea, CO 2 annual means and seasonal variations are also greater than the other KMA stations, indicating that it is affected not only by local vegetation, but also added anthropogenic sources. Selected baseline CO 2 at AMY and at JGS in the west of South Korea is more sensitive to East Asia (e.g., China) according to wind direction and speed. Through the comparison of long-term trends and growth rates at AMY with other East Asian stations over 15 years, it was suggested that they could be affected not only by local vegetation but also by measurement quality.Published by Copernicus Publications on behalf of the European Geosciences Union.

In Situ Aircraft Measurements of CO2 and CH4: Mapping Spatio-Temporal Variations over Western Korea in High-Resolutions

“…Although the CM mission was unable to cover the whole day of each month, that the observed values compare well with the observations at AMY and Gosan (33.30 ˚N, 126.16 ˚E) GAW background stations in Korea, which show a minimum in August and a maximum in April [14]. As per a previous study, the CO2 observed in the vicinity of megacity regions (Nanjing, Beijing, Shanghai, and Lin'an) showed high levels in winter, but in spring in remote stations (AMY, Gosan, Waliguan, and Shangdianzi) in Northeast Asia [14,34]. This is likely due to stronger biogenic emissions in spring with rising air temperature in rural and remote sites compared to densely-populated urban sites with higher fossil fuel emissions in winter.…”

“…Such trans-boundary pollutant transports go through the lower troposphere, including the atmospheric boundary layer and lower free atmosphere in the Korean region, and have been frequently observed in airborne and surface measurements [14][15][16]. Previous studies also show that Korean domestic emissions play an important role in determining the air quality in Korea [14] based on the Korea-United States Air Quality (KORUS-AQ) field campaign, which was performed based on an international collaboration between the Republic of Korea (hereafter Korea) and the United States, led by the National Institute of Environmental Research of Korea and the National Aeronautics and Space Administration (NASA), respectively. The KORUS-AQ campaign was conducted over Korea and its surrounding regions for the period from May to June 2016, and observations obtained from the campaign were utilized to quantify the contribution towards understanding air quality and factors controlling air quality in the region.…”

“…Separately, the atmospheric vertical profiles are measured for altitude range between 0.6 km and 9.0 km over the AMY station (36.53 • N, 126.32 • E), a GAW regional background station [14], coincided with overpasses of the Greenhouse Gases Observing Satellite (GOSAT). Li et al [16] found that the CO 2 observed in the free troposphere, 1.5-8 km above the mean sea level, in 2018 are smaller than the AMY GAW surface station data in spring but agree closely in summer; however, the CO 2 are consistent with the aircraft measurements over the Western Pacific conducted by the Japan Meteorological Agency.…”

“…The Korean Peninsula is subject to large trans-boundary pollutant transports from international sources, such as industrialized regions in China [10][11][12]; pollution from Southern EA also enter the region [13]. Such trans-boundary pollutant transports go through the lower troposphere, including the atmospheric boundary layer and lower free atmosphere in the Korean region, and have been frequently observed in airborne and surface measurements [14][15][16]. Previous studies also show that Korean domestic emissions play an important role in determining the air quality in Korea [14] based on the Korea-United States Air Quality (KORUS-AQ) field campaign, which was performed based on an international collaboration between the Republic of Korea (hereafter Korea) and the United States, led by the National Institute of Environmental Research of Korea and the National Aeronautics and Space Administration (NASA), respectively.…”

Observations of atmospheric 14CO2 at Anmyeondo GAW station, South Korea: implications for fossil fuel CO2 and emission ratios

“…The analysis methods for ( 14 CO 2 ) are described by Lehman et al (2013). Measurement repeatability of ( 14 CO 2 ) in aliquots of whole air extracted from surveillance cylinders is 1.8 ‰ (1σ ), roughly equating to 1 µmol mol −1 C ff detection capability from the measurement uncertainty alone.…”