• Journal of Ecology and Environment
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• 제30권1호
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• pp.23-38
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• 2007

Based on a time series of ocean climate indices and catch records for seven pelagic fish species in the Tsushima Warm Current (TWC) and Kuroshio-Oyashio Current (KOC) regions from 1910 to 2004, we detected regional synchrony in the long-term fluctuations of the fish populations and identified alternation patterns of dominant species related to climate shifts. The annual catches of Pacific herring, Japanese sardines, Japanese anchovies, jack mackerel, chub mackerel, Pacific saury and common squid in the TWC region fluctuated in phase with those in the KOC region, which suggests that they were controlled by the same basin-wide climate forcing. After the collapse of the herring fishery, the alternation sequence was: sardines (1930s), Pacific saury, jack mackerel, common squid and anchovies ($1950s{\sim}1960s$), herring ($late\;1960s{\sim}early\;1970s$), chub mackerel (1970s) and then sardines (1980s). As sardine biomass decreased in the late stages of the cool regime, catch of the other four species increased immediately during the warm period of the 1990s. Regional differences in the amplitude of long-term catch fluctuations for the seven pelagic fishes could be explained by regional differences in availability, fishing techniques and activity.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.232-235
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• 2003

In general, the parameters of climate change include aerosol chemical compounds, aerosol optical depth, greenhouse gases(carbon dioxide, CFCs, methane, nitrous oxide, tropospheric ozone), ozone distribution, precipitation acidity and chemical compounds, persistent organic pollutants and heavy metals, radioactivity, solar radiation including ultra-violet and standard meteorological parameters. Over the last ten years, the monitoring activities of Korea regarding to the climate change have been progressed within the WMO GAW and ACE-Asia IOP programs centered at the observation sites of Anmyeon and Jeju Gosan islands respectively. The Greenhouse gases were pointed out that standard air quality monitoring techniques are required to enhance data comparability and that data presentation formats need to be harmonized and easily understood. Especially, the impact of atmospheric aerosols on climate depends on their optical properties, which, in turn, are a function of aerosol size distribution and the spectral reflective indices. Aerosol optical depth and single scattering albedo in the visible are used as the two basic parameters in the atmospheric temperature variation studies. The former parameter is an indicator of the attenuation power of aerosols, while the latter represents the relative strength of scattering and absorption by aerosols. For aerosols with weak absorption, surface temperature decreases as the optical depth increases because of the domination of backscattering. For aerosols with strong absorption, however, warming could occur as the optical depth increases. The objective of the study is to characterize the means, variability, and trends of Greenhouse gases and aerosol properties on a regional basis using data from its baseline observatories in Korea peninsula. A further goal is to understand the factors that control radiative forcing of the greenhouse and aerosol.

• 대기
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• 제21권3호
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• pp.319-336
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• 2011

The objective of this study was to assess the meteorological capability of Korea by comparing with that of the U.S. and Japan as of 2010. The research was conducted based on various indices and surveys, and quantified the results using the Gordon's scoring model. The index assessment used 11 items derived from 9 segments - surface observation, advanced observation and observations quality in the observation field; data assimilation, numerical model and infrastructure in the data processing field; forecast accuracy in the forecast field; climate prediction and climate change in the climate field - in this research, we classified the meteorological technology into four fields. In the survey assessment, another 10 items in addition to the above 11 ones (total 21 items) were used. In the field of climate, Korea was found to lag far behind the U.S. (96.5p) and Japan (90.5p) with 77.6 points out of 100, which is 18.9 and 12.9 points lower than them respectively. On the other hand, Korea showed the narrowest gap with Japan (95.3p) and the U.S. (94.2) in the forecasting field, recording 90.3 points. Particularly, in surface observation, infrastructure and forecast accuracy segment, Korea was on a par with the U.S. and Japan, boasting 100.5 percent compared to their counterparts. However, in advanced observation, data quality and climate change segment, Korea was only at the level of 81.5 percent compared to that of the U.S. and Japan. All in all, the technological prowess of Korea, scoring 84.6 points, stood at 89.7 percent of that of the U.S. (94.3p) and 91.9 percent of Japan (92.1p).

• 한국수자원학회논문집
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• 제47권1호
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• pp.71-82
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• 2014

본 연구에서는 기후변화에 따른 미래 기후, 수문정보로부터 가뭄전망 정보를 생산 및 분석하고자 한다. 미래의 불확실성을 고려하기위해 3개 GCMs와 3개 수문모형을 이용하였다. 강수량, 유출량 및 토양수분량으로부터 기상학적, 수문학적 및 농업적 가뭄지수로 분류되는 SPI, SRI 및 SSI를 산정하였다. Mann-Kendall test 결과, 미래 가뭄의 경향은 봄철 및 겨울철에 크게 증가할 것으로 전망되었으며, 가뭄발생빈도의 경우 SRI 및 SSI가 SPI 보다 더 높게 나타났다. 미래 기후변화가 기상학적 가뭄 보다는 수문학적 및 농업적 가뭄에 큰 영향을 미치는 것으로 확인되었다.

• 한국농림기상학회지
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• 제19권3호
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• pp.110-119
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• 2017

평년의 기온분포도의 제작방법에 따라 이를 활용하여 산출되는 농업기후정보에 어느 정도의 오차를 유발하는지 평가하고자 하였다. 1983-2012 기간에 발생한 기온을 일별로 평균하여 배경기온(365일 ${\times}$ 1세트)을 준비하고, 여기에 소기후모형을 적용하여 평균된 일별 기온분포도('EST 평년' 기온)를 제작하였다. 또한 30년동안 발생한 매년, 매일의 배경기온(365일 ${\times}$ 30세트)으로부터 실황 추정용 소기후모형에 적용하여 30세트의 기온분포도를 제작한 후 일 단위로 다시 평균한 기온분포도('OBS 평년' 기온)를 참값으로 간주하여 비교하였다. 평년 기온분포도에 따라 '후지' 사과의 개화일과 종상일을 예측하고, 늦서리의 위험정도를 비교한 결과, 휴면에 진입하는 늦가을 이후부터 봄철까지의 기온을 온도시간단위로 환산하여 사용하는 개화일의 경우, 평균 2.9일의 오차를 보인 반면, 4월의 최저기온 분포를 2차방정식에 대입하여 산출한 종상일의 경우 평균 11.4일의 비교적 큰 오차가 발생하는 것으로 나타났다. 또한, 늦서리의 위험을 판정하는 방법은 개화일과 종상일의 편차를 이용하는데 EST 평년 기온을 근거로 판정할 경우, 하동군 악양면의 12.5% 면적에 해당하는 농가는 종상일이 개화일과 같거나 늦게 출현하여 위험지역으로 분류되었지만, OBS 평년 기온에 따르면 악양면의 모든 지역에서 종상일이 개화일보다 늦게 나타나는 곳은 없었다. 차후 컴퓨터 자원과 구동시간에 큰 제약이 없다면 실황 추정기술에 따라 평년기간 30세트의 일별자료를 복원하여 기존 EST 평년 자료를 대체하는 것이 필요하다고 판단된다.

• 한국습지학회지
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• 제26권2호
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• pp.160-167
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• 2024

양서류는 오염 및 개발로 인한 위협을 경고하는 환경지표종이며, 그들의 신체 상태와 주변 서식 환경 정보는 생태계 건강성을 파악할 수 있는 중요한 지표로 이용될 수 있다. 본 연구의 목적은 멸종위기 야생동물 II 급 맹꽁이의 출현 시기 및 성별에 따른 신체 상태와 암수가 출현한 기후환경 차이를 알아보기 위해 수행되었다. 서울특별시 강동구 고덕동 일대에 서식하는 맹꽁이를 대상으로 2018년 6월부터 10월까지 총 53회 조사를 수행하였고, 각 개체별 무게와 길이를 이용하여 신체 상태 지수(SMI, Scaled mass index)를 산출하였다. 그 결과, 수컷 235개체, 암컷 161개체 총 396개체를 포획하였고, 암컷은 수컷보다 SVL이 길고, 무게가 무거웠으며 신체 상태 지수 또한 높게 확인되었다. 월별 신체 상태 지수는 6월에 수컷이 암컷보다 낮았고, 7월부터 9월까지 암수 간 차이를 보이지 않았다. 암컷과 수컷이 출현한 기후환경 중 강우량과 습도와 관련된 환경변수들은 차이를 보였다. 이러한 연구 결과는 추후 맹꽁이에게 적합한 서식환경을 확인하고 개발로 인한 대체서식지를 선정하는 데도 중요한 기초정보를 제공할 수 있을 것으로 판단된다.

• 대한원격탐사학회지
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• 제33권5_2호
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• pp.641-645
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• 2017

본 연구는 중국 동북지역의 22개 농업기후지대별로 유효적산온도(GDD), 무상기간(FFP) 작물생육 기간(GSL) 등 3가지 농업기후지수를 비교하기 위해 수행되었다. 농업기후지수는 NASA의 MERRA-2 기상 자료를 이용하여 계산하였다. 분석결과 모든 농업기후지수는 연도별로 유의한 차이는 보이지 않았다. 하지만 농업기후지대별로는 유의한 차이를 보였다. GDD는 지역별로 531.7-1650.6 도일의 범위를 보였으며, FFP는 141.5-241.7일의 범위를 나타내었다. 그리고 GSL은 125.1-217.9일의 공간적 분포를 보였다.

• 대한원격탐사학회지
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• 제36권4호
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• pp.627-635
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• 2020

With the increasing severity of climate change, intense torrential rains are occurring more frequently globally. Flooding due to torrential rain not only causes substantial damage directly, but also via secondary events such as landslides. Therefore, accurate and prompt flood detection is required. Because it is difficult to directly access flooded areas, previous studies have largely used satellite images. Traditionally, water indices such asthe normalized difference water index (NDWI) and modified normalized difference water index (MNDWI) which are based on different optical bands acquired by satellites, are used to detect floods. In addition, as flooding likelihood is greatly influenced by the weather, synthetic aperture radar (SAR) images have also been used, because these are less influenced by weather conditions. In this study, we compared flood areas calculated from SAR images and water indices derived from Landsat-8 images, where the images were acquired at similar times. The flooded area was calculated from Landsat-8 and Sentinel-1 images taken between the end of May and August 2019 at Lijiazhou Island, China, which is located in the Changjiang (Yangtze) River basin and experiences annual floods. As a result, the flooded area calculated using the MNDWI was approximately 21% larger on average than that calculated using the NDWI. In a comparison of flood areas calculated using water indices and SAR intensity images, the flood areas calculated using SAR images tended to be smaller, regardless of the order in which the images were acquired. Because the images were acquired by the two satellites on different dates, we could not directly compare the accuracy of the water-index and SAR data. Nevertheless, this study demonstrates that floods can be detected using both optical and SAR satellite data.

• 한국농공학회논문집
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• 제64권6호
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• pp.101-112
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• 2022

Extreme precipitation events have recently become a leading cause of disasters. Thus, investigating the variability and trends of extreme precipitation is crucial to mitigate the increasing impact of such events. Spatial distribution and temporal trends in annual precipitation and four extreme precipitation indices of duration (CWD), frequency (R10 mm), intensity (Rx1day), and percentile-based threshold (R95pTOT) were analyzed using the daily precipitation data of 10 observation stations in Chungcheong province during 1974-2020. The precipitation at all observation stations, except the Boryeong station, showed nonsignificant increasing trends at 95% confidence level (CL) and increasing magnitudes from the west to east regions. The high variability in mean annual precipitation was more pronounced around the northeast and northwest regions. Similarly, there were moderate to high patterns in extreme precipitation indices around the northeast region. However, the precipitation indices of duration and frequency consistently increased from the west to east regions, while those of intensity and percentile-based threshold increased from the south to east regions. Nonsignificant increasing trends dominated in CWD, R10 mm, and Rx1day at all stations, except for R10 mm at Boeun station and Rx1day at Cheongju and Jecheon stations, which showed a significantly increasing trend. The spatial distribution of trend magnitude shows that R10 mm increased from the west to east regions. Furthermore, variations in precipitation were very strongly correlated (99% CL) with R10 mm, Rx1day, and R95pTOT at all stations, except with wR10 mm at Cheongju station, which was strongly correlated with a 95% CL.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.163-163
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• 2023

Flooding has become an increasing event which is one of the major natural disasters responsible for direct economic damage in South Korea. Driven by climate change, precipitation extremes play significant role on the flood damage and its further increase is expected to exacerbate the socioeconomic impact in the country. However, the empirical evidence associating changes in precipitation extremes to the historical flood damage is limited. Thus, there is a need to assess the causal relationship between changes in precipitation extremes and flood damage, especially in agricultural region like Chungcheong region in South Korea. The spatial and temporal changes of precipitation extremes from 10 synoptic stations based on daily precipitation data were analyzed using the ClimPACT2 tool and Mann-Kendall test. The four precipitation extreme indices consisting of consecutive wet days (CWD), number of very heavy precipitation wet days (R30 mm), maximum 1-day precipitation amount (Rx1day), and simple daily precipitation intensity (SDII), which represent changes in intensity, frequency, and duration, respectively, and the time series data on flooded area and flood damage from 1985 to 2020 were used to investigate the causal relationship in the ARDL-ECM framework and pairwise Granger causality analysis. The trend results showed that majority of the precipitation indices indicated positive trends, however, CWD showed no significant changes. ARDL-ECM framework showed that there was a long-run relationship among the variables. Further analysis on the empirical results showed that flooded area and Rx1day have significant positive impacts on the flood damage in both short and long-runs while R30 mm only indicated significant positive impact in the short-run, both in the current period, which implies that an increase in flooded area, Rx1day, and R30 mm will cause an increase in the flood damage. The pairwise Granger analysis showed unidirectional causality from the flooded area, R30 mm, Rx1day, and SDII to flood damage. Thus, these precipitation indices could be useful as indicators of pluvial flood damage in Chungcheong region of South Korea.