• Asian Journal of Atmospheric Environment
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• 제7권2호
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• pp.85-94
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• 2013

Methane concentrations have been monitored at the Anmyeon-do Observatory, Korea, since 1999. In recent years, the methane concentration has increased, but the sources of this increase have yet to be identified. This study was designed to identify the major source contributing to the increase by using World Data Centre for Greenhouse Gases (WDCGG) data and the Greenhouse Gases Emission Presumption (GEP) method. The data were collected at Anmyeon-do between 2003 and 2009 (except 2008), and the analyses showed that the increase in methane concentration originated mainly in rice paddies around the observation point. The annual average methane concentration at Anmyeon-do was 1894 ppb, of which 100-103 ppb (5.3-5.4%) was shown to originate mainly from rice paddies. The seasonal fluctuation in methane concentration from May to October estimated by the GEP method was compared with experimental data of previous research conducted on rice paddies. The close match obtained through this comparison shows that the GEP method is effective. The difference in methane concentration was also analyzed in terms of land use and land cover. It was shown that although rice paddies account for only 14.7% of the area surveyed, they accounted for between 69 and 90% of the total increase in methane concentration. These results confirm that rice paddies are the main source of the increase in methane concentration observed at Anmyeon-do.

• 한국대기환경학회지
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• 제17권3호
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• pp.277-288
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• 2001

Continuous atmospheric CO$_2$measurements measured during the 1 year(1998.8∼1999.8) at Korea Global Atmosphere Watch Observatory (KGAWO) in Anmyeon-do are analyzed by the selecting method which is recommended by WDCGG to get background CO$_2$. This method can reject data based on two criteria: the instability of CO$_2$ concentration within 1 hour from hourly standard deviation (hourly variability$\leq$ 0.6 ppm first selection) and the large changes in the CO$_2$ concentration from one hour to the nex(∼$\leq$0.3 ppm, second selection). We could obtain hourly background CO$_2$ of 37% in first selection and 20% in second selection during the l year. That are a little less than those of Ryori station in Japan. especially, the cases of background CO$_2$ which is selected were few during the summer. That is caused by affection of vegetation and anthropogenic source. After the selecting methods are applied, the cases which is selected for easterly wind decrease remarkably according to the analysis of wind direction about continuous CO$_2$ .That was affected by anthropogenic source from the east area.

• Asian Journal of Atmospheric Environment
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• 제5권4호
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• pp.263-277
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• 2011

Global atmospheric $CO_2$ distributions were simulated with a chemical transport model (GEOS-Chem) and compared with space-borne observations of $CO_2$ column density by GOSAT from April 2009 to January 2010. The GEOS-Chem model simulated 3-D global atmospheric $CO_2$ at $2^{\circ}{\times}2.5^{\circ}$ horizontal resolution using global $CO_2$ surface sources/sinks as well as 3-D emissions from aviation and the atmospheric oxidation of other carbon species. The seasonal cycle and spatial distribution of GEOS-Chem $CO_2$ columns were generally comparable with GOSAT columns over each continent with a systematic positive bias of ~1.0%. Data from the World Data Center for Greenhouse Gases (WDCGG) from twelve ground stations spanning $90^{\circ}S-82^{\circ}N$ were also compared with the modeled data for the period of 2004-2009 inclusive. The ground-based data show high correlations with the GEOS-Chem simulation ($0.66{\leq}R^2{\leq}0.99$) but the model data have a negative bias of ~1.0%, which is primarily due to the model initial conditions. Together these two comparisons can be used to infer that GOSAT $CO_2$ retrievals underestimate $CO_2$ column concentration by ~2.0%, as demonstrated in recent validation work using other methods. We further estimated individual source/sink contributions to the global atmospheric $CO_2$ budget and trends through 7 tagged $CO_2$ tracers (fossil fuels, ocean exchanges, biomass burning, biofuel burning, net terrestrial exchange, shipping, aviation, and CO oxidation) over 2004-2009. The global $CO_2$ trend over this period (2.1 ppmv/year) has been mainly driven by fossil fuel combustion and cement production (3.2 ppmv/year), reinforcing the fact that rigorous $CO_2$ reductions from human activities are necessary in order to stabilize atmospheric $CO_2$ levels.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 1999년도 추계학술대회 논문집
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• pp.269-271
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• 1999

온실기체농도에 대한 감시는 전세계적으로 미국의 NOAA(National Oceanic and Atmospheric Administration)/CMDL(Climate Monitoring and Diagnostic Laboratories)의 관측망을 비롯하여 세계기상기구(WMO)의 지구대기감시(GAW)계획에 의하여 수행되고 있다(Keeling et al., 1976 ; Komhyr et al., 1989). 기상청에서는 온실기체의 관측을 위하여 1994년에 전남 무안의 무안기상대에 비분산적외선 이와 같이 측정된 $CO_2$농도자료가 배경대기관측자료로써의 신뢰를 받기 위해서는 적절한 질관리를 통하여 인간 및 생물의 활동에 의한 직접적인 영향 제거하여야 한다.(중략)

• 한국기후변화학회지
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• 제2권1호
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• pp.1-14
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• 2011

제주 고산 지역의 이산화탄소(이하 $CO_2$) 농도 현황을 분석하기 위해 세계 온실가스 자료 센터(이하 WDCGG)에 등록되어 있는 관측소 농도와 비교한 결과, 청정한 지역인 남반구보다 인구가 밀집해 있고, 산업 활동이 활발한 북반구의 농도가 더 높게 나타났으며, 특히 북반구 중에서도 한반도를 포함한 아시아 지역 농도가 최근 급증하고 있는 이 지역 $CO_2$ 배출량으로 인해 가장 높게 나타났다. 특히, 제주 고산 지역은 아시아 다른 관측소와 비교하여 농도값이 다소 높게 나타나는 경향을 보였으며, 그 요인을 분석하기 위해 고농도 사례를 선정하여 계절별 분석을 수행하였다. 그 결과, 1월에는 서고/동저의 기압배치가 형성되어 중국으로부터의 기류가 유입되었을 때 고농도가 발생하였으며, 일반대기오염물질의 농도비를 이용한 요인 분석 및 역궤도 추적에서도 장거리 이동에 의한 영향인 것으로 나타났다. 반면, 8월에는 국지적인 영향으로 인한 고농도 사례가 많았으며, 이는 북태평양 고기압에 의해 대기가 정체되어 식물의 호흡작용에 의해 발생한 $CO_2$가 축적되면서 야간 시간대에 급격한 농도 증가 때문인 것으로 보인다. 5월, 11월에는 이동성 저기압에 의해 중국으로부터의 기류가 유입되면서 장거리 이동에 의한 고농도 사례가 많았으며, 5월 25~27일의 황사 사례에서도 높은 $CO_2$ 농도값이 나타났다.

• 한국대기환경학회지
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• 제23권4호
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• pp.487-497
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• 2007

Increase of the greenhouse gases emissions during last century has led remarkable changes in our environment and climate system. Continuous monitoring of atmospheric constituents over the world is positively necessary to understand these changes around us. The concentrations of greenhouse gases ($CO_2,\;CH_4,\;N_2O,\;CFCs$) have been continuously measured at Global Climate Change Monitoring station in Gosan, Jeju since January, 2002. In this study, the variation characteristics of greenhouse gases as well as their annual, seasonal and diurnal trend using the data from January, 2002 to December, 2005 were analyzed. The raw data which was used in the analysis were validated with the methods recommended by WDCGG (World Data Center for Greenhouse Gases). The concentration of $CO_2$ was increasing continuously by 2.1 ppm/year, while $CH_4$ did not show any increasing or decreasing trend clearly for 4 years. The concentration of $N_2O$ was slightly increasing and CFCs were decreasing except CFC-12 which has longer lifetime compared with other CFCs. The variations of the greenhouse gases at Gosan were shown to be consistent with the global trend. But the concentration level of $CO_2$ in Korea was more or less higher than abroad.