• 대기
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• 제27권2호
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• pp.163-175
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• 2017

The global terrestrial ecosystems have shown a large spatial variability in recent decades and represented a carbon sink pattern at mid-to-high latitude in Northern Hemisphere. However, there are many uncertainties in magnitude and spatial distribution of terrestrial carbon fluxes due to the effect of climate factors. So, it needs to accurately understand the spatio-temporal variations on carbon exchange flux with climate. This study focused on the effects of climate factors, .i.e. temperature, precipitation, and solar radiation, to terrestrial biosphere carbon flux. We used the terrestrial carbon flux that is simulated by a CarbonTracker, which performs data assimilation of global atmospheric $CO_2$ mole fraction measurements. We demonstrated significant interactions between Net Ecosystem Production (NEP) and climate factors by using the partial correlation analysis. NEP showed positive correlation with temperature at mid-to-high latitude in Northern Hemisphere but showed negative correlation pattern at $0-30^{\circ}N$. Also, NEP represented mostly negative correlation with precipitation at $60^{\circ}S-30^{\circ}N$. Solar radiation affected NEP positively at all latitudes and percentage of positive correlation at tropical regions was relatively lower than other latitudes. Spring and summer warming had potentially positive effect on NEP in Northern Hemisphere. On the other hand as increasing the temperature in autumn, NEP was largely reduced in most northern terrestrial ecosystems. The NEP variability that depends on climate factors also differently represented with the type of vegetation. Especially in crop regions, land carbon sinks had positive correlation with temperature but showed negative correlation with precipitation.

• 통합자연과학논문집
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• 제13권1호
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• pp.27-33
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• 2020

The unsustainable human activities like increased use of automobiles, heavy industrialization and the use of large volumes of fertilizers, chemicals and pesticides in the agricultural land cause climate change problems in one way or another. Under normal circumstances, the heat radiations from the sun will be reflected back. An excessive volume of GHGs in the atmosphere would prevent these radiations from reflecting back. East Asia is facing severe climate change issues in recent times. A lot of climate change problems such as hurricanes and floods have been reported from this region in the last couple of decades. The study aimed at investigating the climate change in East Asia with changing Sea Surface Temperature (SST). The study adopted a quantitative research method with a case study research design where a deliberate focus was made on the East Asia Region. Secondary data was gathered and analyzed to yield both descriptive and inferential statistics. The study concluded that the impact of East Asia Climate variability was significant mainly for some extreme events. Also, the study concluded that there was a significant link between the change of the East Asia climate variability and that of the sea surface temperature. Further, the study concluded that a linear relationship existed between the sea surface temperature and the climate of East Asia. Hence, a linear regression was a significant predictor of the East Asia Climate (EAC) based on changing sea surface temperature. The model revealed that 37.4% of the variations in the climate change index were explained by the changes in the sea surface temperature. The climate was expected to change with a value of 49.48 for a unit change in the sea surface temperature.

• Asian Journal of Atmospheric Environment
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• 제5권4호
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• pp.278-291
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• 2011

Korea has experienced dramatic development and has become highly industrialized and urbanized during the past 40 years, which has resulted in rapid economic growth. Due to the industrialization and urbanization, however, air pollutant emission sources have increased substantially. Rapid increases in emission sources have caused Korea to suffer from serious air pollution. An air pollutant emissions inventory is one set of essential data to help policymakers understand the current status of air pollution levels, to establish air pollution control policies and to analyze the impacts of implementation of policies, as well as for air quality studies. To accurately and realistically estimate administrative district level air pollutant emissions of Korea, we developed a Korean Emissions Inventory System named the Clean Air Policy Support System (CAPSS). In CAPSS, emissions sources are classified into four levels. Emission factors for each classification category are collected from various domestic and international research reports, and the CAPSS utilizes various national, regional and local level statistical data, compiled by approximately 150 Korean organizations. In this paper, we introduced for the first time, a Korean national emissions inventory system and release Korea's official 2007 air pollutant emissions for five regulated air pollutants.

• 한국방재학회 논문집
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• 제7권5호
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• pp.73-78
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• 2007

전세계적으로 지구온난화와 기상이변으로 인한 인명과 재산의 피해는 해마다 증가하고 있으며, 최근 한반도의 기후와 기온은 지구평균치보다 큰 변화가 일어나고 있다. 지구전체기상모형(Global Climate Model 또는General Circulation Model GEM)보다 고해상도의 모의가 가능한 지역기상모형(Regional Climate Model RCM)은 기후 변동, 변화 및 그 영향과 관련된 여러 문제들을 파악하는데 사용된다. 이러한 기상모형을 위한 기존 입력자료들의 가용성, 정확도, 그리고 일관성의 결여로 인하여 제한되고 있는 모형의 예측능력 향상을 위해 새로운 지표경계조건들(Surface Boundary Condition SBC)의 필요성이 요구되고 있다. 따라서, 정확도 높은 측정자료의 확보와 과학적 근거에 의한 자료선택 및 결측보정이 새로운 지표경계조건 구축에 선결조건이 되어야 한다. 이 연구의 목적은, 기상방재 수립을 위한 아시아 지역기상모형에 필요한 정확도 높은 지표경계조건 자료를 구축하는데 있다. 산정된 지표경계조건들은 30km 크기의 격자망으로 구성된 한반도를 포함한 아시아 지역기상모형의 계산망에 대해 구축되어, 이 지역의 기상 및 수문 예측모의를 위한 다른 분포형모형들의 입력자료로도 사용이 가능하다.

• 한국초지조사료학회지
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• 제42권2호
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• pp.127-136
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• 2022

본 연구는 기계학습을 기반으로 제작한 수량예측모델을 통해 이상기상에 따른 사일리지용 옥수수(WCM)의 피해량 산정 및 전자지도를 작성할 목적으로 수행하였다. WCM 데이터는 수입적응성 시험보고서(n = 1,219), 국립축산과학원 시험연구보고서(n = 1,294), 한국축산학회지(n = 8), 한국초지조사료학회지(n = 707) 및 학위논문(n = 4)에서 총 3,232점을 수집하였으며 기상 데이터는 기상청의 기상자료개방포털에서 수집하였다. 본 연구에서 이상기상에 따른 WCM의 피해량은 WMO 방식을 준용하여 산정하였다. 정상기상에서 DMY 예측값은 13,845~19,347 kg/ha 범위로 나타났으며 피해량은 이상기온, 이상강수량 및 이상풍속에서 각각 -305~310, -54~89 및 -610~813 kg/ha 범위로 나타났다. 최대 피해량은 이상풍속에서 813 kg/ha로 나타났다. WMO 방식을 통해 산정한 WCM의 피해량은 QGIS를 이용하여 전자지도로 제시하였다. 이상기상에 따른 WCM의 피해량 산정시 데이터가 없어 공백인 지역이 존재하여 이를 보완하기 위해 종관기상대보다 많은 지점의 데이터를 제공하고 있는 방재기상대를 이용하면 보다 세밀한 피해량을 산정할 수 있을 것이다.

• 한국농림기상학회지
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• 제25권4호
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• pp.368-375
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• 2023

본 연구에서는 농촌진흥청과 홍콩과학기술대학교의 공동 개발로 생산된 1개월 예측 자료의 오차를 분석하고, 통계적 보정 기법을 활용한 오차 개선 효과를 살펴보고자 하였다. 이를 위해 2013년부터 2021년까지의 과거 예측(hindcast) 자료, 기상관측자료, 다양한 환경정보들을 수집하고 다양한 환경 조건에서의 오차 특성을 분석하였다. 최고기온과 최저기온의 경우, 해발고도와 위도가 높을 수록 예측 오차가 더 크게 나타났다. 평균적으로, 선형회귀모형과 XGBoost로 보정한 예측자료는 보정 전 예측자료보다 각각 0.203, 0.438(최고기온) 및 0.069, 0.390(최저기온) 정도의 RMSE가 감소했으며, 높은 고도와 위도에서의 오차 개선이 더 크게 나타났다. 모든 분석 조건에서 XGBoost가 선형회귀모형보다 우수한 오차 개선 효과를 나타냈다. 본 연구를 통해 예측 자료의 오차가 지형적 조건에 영향을 받는다는 사실을 확인하였고, XGBoost와 같은 기계학습법이 다양한 환경인자들을 고려하여 효과적으로 오차를 개선할 수 있다는 것을 확인하였다.

• 한국농림기상학회지
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• 제23권4호
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• pp.391-404
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• 2021

본 연구에서는 최신의 연구 트렌드인 빅데이터와 인공지능을 농업분야에 접목하여 유전자 알고리즘(GA)과 전지구 기후 재분석 자료를 활용한 마늘 생산량의 장기 예측 모형을 개발하고 그 예측성능을 평가해 보았다. 해당 모형은 마늘의 파종량을 수정할 수 있는 11월에 예측 자료를 생산하므로, 마늘의 생산 시기와 시간공간적으로 떨어진 전지구 기후 재분석 자료로부터 마늘생산량의 예측 인자로 활용할 수 있는 시그널을 찾아 장기적 마늘 생산량 예측에 활용하였다. 그 결과 결정론적 예측과 확률론적 예측 모두 마늘 생산량의 경년변동성을 통계적으로 99% 신뢰수준에서 관측과 유사하게 모의하였으며, 범주형 예측에서도 이분위 예측에서 93.3%, 삼분위 예측에서 73.3%의 적중률을 보이며 우수한 예측 성능을 나타내었다. 또한, 예측인자들 사이의 선형 및 비선형적 관계를 모두 고려하는 GA방법을 사용하였을 때, 선형적 앙상블 방법을 적용하였을 때 보다 높은 예측성능과 안정적인 예측결과를 보이는 것을 알 수 있다. 본 연구에서 개발된 마늘 생산량 예측 모형은 기존의 단기예측 위주의 농산물 생산량 예측의 한계를 극복하고 한 해의 농사가 시작되기 전 잠재 생산량을 전망 정보를 생산하여 농산물의 수요·공급 및 가격안정화를 위한 장기적 계획을 수립하는 것에 도움이 될 것으로 생각된다.

• 한국환경복원기술학회지
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• 제24권6호
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• pp.1-13
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• 2021

This study was performed to investigate the ecosystem service patterns in relation to climate change acceleration utilizing big data analysis. This study aimed to use big data analysis as one of the network of views to identify convergent thinking in two fields: climate change and ecosystem service. The keywords were analysed to ascertain if there were any differences in the perceiving problems, policy direction, climate change implications, and regional differences. In addition, we examined the research keywords of each continent, the centre of ecosystem service research, and the topics to be referred to in domestic research. The results of the analysis are as follows: First, the keyword centrality of climate change is similar to the detailed indicators of The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) regulations, content, and non-material ecosystem services. Second, the cross-analysis of terms in two journals showed a difference in value-oriented point; the Ecosystem Service Journal identified green infrastructure as having economic value, whereas the Climate Change Journal perceives water, forest, carbon, and biodiversity as management topics. The Climate Change Journal, but not the former, focuses on future predictions. Third, the analysis of the research topics according to continents showed that water and soil are closely related to the economy, and thus, play an important role in policy formulation. This disparity is due to differences in each continent's environmental characteristics, as well as economic and policy issues. This fact can be used to refer to the direction of research on ecosystem services in Korea. Consistent with the recent trend of expanding research regarding the impacts of climate change, it is necessary to study strategies to scientifically predict and respond to the negative effects of climate change.

• 한국농공학회논문집
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• 제57권4호
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• pp.101-112
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• 2015

This study was conducted to predict greenhouse gas (GHG) emission from a radish field by future climate change scenario. A radish field located at Chuncheon-si Gangwon-do was selected, and A1B Special Report on Emission Scenario (SRES) of the IPCC (Intergovernmental panel on climate change) was applied to simulate the future potential climate change. Rainfall and temperature data were predicted to be increased by 8.4 % and 1.9 % in 2040s, 35.9 % and 27.0 % in 2060s, 19.2 % and 30.8 % in 2090s, respectively, compared to the climate data in 2010s. The $N_2O$, $CO_2$, and $CH_4$ emission were estimated to be increased by 0.4 up to 2.4 kg/ha/yr, by 500.5 up to 734.5 kg/ha/year, and by 29.4 up to 160.4 kg/ha/yr, which were resulted from the global warming potential (GWP) of 14.5~21.7 $CO_2$/ha/year caused by the amount changes of rainfall, temperature, manure amendment, and fertilizer applied in fields. One distinct feature of the study result was that the changes of $N_2O-N$, $CH_4-C$ and $CO_2-C$ with future potential climate change simulation were varied by soil texture. Therefore it was concluded that there is a need to apply appropriate amount of manure amendment needs and to consider soil texture as well.

• 한국환경과학회지
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• 제10권6호
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• pp.423-429
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• 2001

Satellite data, with sea surface temperature(557) by NOAA and sea level(SL) by Topex/poseidon, are used to estimate characteristics on the variations and correlations of 557 and SL in the East Asian Seas from January 1993 through May 1998. We found that there are two climatic characteristics in the East Asian seas the oceanic climate, the eastern sea of Japan, and the continental climate, the eastern sea of China, respectively. In the oceanic climate, the variations of SL have the high values in the main current of Kuroshio and the variations of 557 have not the remarkable seasonal variations because of the continuos compensation of warm current by Kuroshio. In the continental climate, SL has high variations in the estuaries(the Yellow River, the Yangtze River) with the mixing the fresh water and the saline water in the coasts of continent and 557 has highly the seasonal variations due to the climatic effect of continents. In the steric variations of summer, the eastern sea of Japan, the East China Sea and the western sod of Korea is increased the sea level about 10~20cm. But the Bohai bay in China have relatively the high values about 20~30cm due to the continental climate. generally the trends of SST and SL increased during all periods. That is say, the slopes of 557 and SL Is presented 0.29$^{\circ}C$/year and 0.84cm/year, respectively. The annual and semi-annual amplitudes have a remarkable variations in the western sea of Korea and the eastern sea of Japan. In the case of the annual peaks, there appeared mainly In the western sea of Korea and the eastern sea of .Japan because of the remarkable variations of SL associated with Kuroshio. But in the case of the semi-annual peaks, there appeared in the eastern sea of Japan by the influence of current, and in the western sea of Korea by the influence of seasonal temperature, respectively. From our results, it should be believed that 557 and SL gradually Increase in the East Asian seas concerning to the global warming. So that, it should be requested In the international co-operation against In the change of the abnormal climate.