• Title/Summary/Keyword: general circulation

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Future drought risk assessment under CMIP6 GCMs scenarios

  • Thi, Huong-Nguyen;Kim, Jin-Guk;Fabian, Pamela Sofia;Kang, Dong-Won;Kwon, Hyun-Han
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.305-305
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    • 2022
  • A better approach for assessing meteorological drought occurrences is increasingly important in mitigating and adapting to the impacts of climate change, as well as strategies for developing early warning systems. The present study defines meteorological droughts as a period with an abnormal precipitation deficit based on monthly precipitation data of 18 gauging stations for the Han River watershed in the past (1974-2015). This study utilizes a Bayesian parameter estimation approach to analyze the effects of climate change on future drought (2025-2065) in the Han River Basin using the Coupled Model Intercomparison Project Phase 6 (CMIP6) with four bias-corrected general circulation models (GCMs) under the Shared Socioeconomic Pathway (SSP)2-4.5 scenario. Given that drought is defined by several dependent variables, the evaluation of this phenomenon should be based on multivariate analysis. Two main characteristics of drought (severity and duration) were extracted from precipitation anomalies in the past and near-future periods using the copula function. Three parameters of the Archimedean family copulas, Frank, Clayton, and Gumbel copula, were selected to fit with drought severity and duration. The results reveal that the lower parts and middle of the Han River basin have faced severe drought conditions in the near future. Also, the bivariate analysis using copula showed that, according to both indicators, the study area would experience droughts with greater severity and duration in the future as compared with the historical period.

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Evaluation and analysis of future flood probabilities in rural watershed based on probability theory (확률론 기반 농촌 유역의 미래 홍수 확률 평가 및 분석)

  • Kwak, Jihye;Lee, Hyunji;Kim, Jihye;Jun, Sang Min;Kim, Seokhyeon;Kim, Sinae;Kang, Moon Seong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.187-187
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    • 2022
  • 우리나라의 농촌 유역은 크게 1) 상류에 위치한 농업용 저수지, 2) 저수지 방류부, 3) 저수지 하류하천, 4) 하류 농업 지대로 구성된다. 이들 모두 유역의 홍수·침수와 연관되어 있으나 각각의 설계 빈도가 서로 달라 일시에 수용 가능한 수자원의 양이 상이하다. 예컨대 극한 강우가 발생한 경우 PMP를 고려하여 설계된 저수지에서는 유입 홍수량이 통제될 수 있으나 50-200년 빈도로 설계된 하류하천에서는 측면 유입량 때문에 홍수가 발생할 수 있다. 따라서 유역의 홍수 확률을 산출할 때에는 유역 구성지역별 홍수 확률을 산정한 후 종합적으로 고려할 필요가 있다. 특히 농촌유역의 경우 하류하천 및 농경지의 설계 빈도 기준이 도시에 비해 낮아 유역 구성요소 간 처리 가능한 수자원 양의 차이가 크다. 따라서 본 연구에서는 농촌 유역을 대상으로 연구를 진행하였다. 한편, 최근 기후변화로 인해 극한 강우 사상의 빈도가 잦아짐에 따라 유역 내 홍수의 발생이 증가하고 있다. 따라서 기후변화에 따른 미래 농촌 유역의 홍수 발생 여부 파악이 필수적이다. 이에 본 연구에서는 CMIP 6 (Coupled Model Intercomparison Project Phase 6)의 GCM (General Circulation Model) 기상산출물을 농촌 유역에 적용함으로써 미래 농촌 유역의 홍수 발생 여부를 확인하고자 하였다. 또한, CMIP 6의 GCM 산출 기상자료의 시간 단위는 24시간 혹은 3시간으로 시간적 해상도가 낮으므로 유역 홍수 모의를 위하여 GCM 산출물의 시간 분해를 수행하였다. 본 연구에서는 MRC (Multiplicative Random Cascade) 모형을 기후변화 시나리오 기상자료에 적용함으로써 강우 자료의 시간 분해를 수행하고, 시간 분해 결과물을 활용하여 농촌 유역의 미래 홍수 확률을 산정해보고자 하였다. 본 연구의 결과는 향후 농촌 유역의 홍수 확률 산정 기법에 관한 기초 자료로 활용될 수 있을 것으로 사료된다.

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Advancing Cardio-Oncology in Asia

  • Choon Ta Ng;Li Ling Tan;Il Suk Sohn;Hilda Gonzalez Bonilla;Toru Oka;Teerapat Yinchoncharoen;Wei-Ting Chang;Jun Hua Chong;Maria Katrina Cruz Tan;Rochelle Regina Cruz;Astri Astuti;Vivek Agarwala;Van Chien;Jong-Chan Youn;Jieli Tong;Joerg Herrmann
    • Korean Circulation Journal
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    • v.53 no.2
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    • pp.69-91
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    • 2023
  • Cardio-oncology is an emerging multi-disciplinary field, which aims to reduce morbidity and mortality of cancer patients by preventing and managing cancer treatment-related cardiovascular toxicities. With the exponential growth in cancer and cardiovascular diseases in Asia, there is an emerging need for cardio-oncology awareness among physicians and country-specific cardio-oncology initiatives. In this state-of-the-art review, we sought to describe the burden of cancer and cardiovascular disease in Asia, a region with rich cultural and socio-economic diversity. From describing the uniqueness and challenges (such as socio-economic disparity, ethnical and racial diversity, and limited training opportunities) in establishing cardio-oncology in Asia, and outlining ways to overcome any barriers, this article aims to help advance the field of cardio-oncology in Asia.

Assessment of the Potential Impact of Climate Change on the Drought in Agricultural Reservoirs under SSP Scenarios (SSP 시나리오를 고려한 농업용 저수지의 이수측면 잠재영향평가)

  • Kim, Siho;Jang, Min-Won;Hwang, Syewoon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.66 no.2
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    • pp.35-52
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    • 2024
  • This study conducted an assessment of potential impacts on the drought in agricultural reservoirs using the recently proposed SSP (Shared Socioeconomic Pathways) scenarios by IPCC (Intergovernmental Panel on Climate Change). This study assesses the potential impact of climate change on agricultural water resources and infrastructure vulnerability within Gyeongsangnam-do, focusing on 15 agricultural reservoirs. The assessment was based on the KRC (Korea Rural Community Corporation) 1st vulnerability assessment methodology using RCP scenarios for 2021. However, there are limitations due to the necessity for climate impact assessments based on the latest climate information and the uncertainties associated with using a single scenario from national standard scenarios. Therefore, we applied the 13 GCM (General Circulation Model) outputs based on the newly introduced SSP scenarios. Furthermore, due to difficulties in data acquisiton, we reassessed potential impacts by redistributing weights for proxy variables. As a main result, with lower future potential impacts observed in areas with higher precipitation along the southern coast. Overall, the potential impacts increased for all reservoirs as we moved into the future, maintaining their relative rankings, yet showing no significant variability in the far future. Although the overall pattern of potential impacts aligns with previous evaluations, reevaluation under similar conditions with different spatial resolutions emphasizes the critical role of meteorological data spatial resolution in assessments. The results of this study are expected to improve the credibility and accuracy formulation of vulnerability employing more scientific predictions.

Remote Cardiac Rehabilitation With Wearable Devices

  • Atsuko Nakayama;Noriko Ishii;Mami Mantani;Kazumi Samukawa;Rieko Tsuneta;Megumi Marukawa;Kayoko Ohno;Azusa Yoshida;Emiko Hasegawa;Junko Sakamoto;Kentaro Hori;Shinya Takahashi;Kaoruko Komuro;Takashi Hiruma;Ryo Abe;Togo Norimatsu;Mai Shimbo;Miyu Tajima;Mika Nagasaki;Takuya Kawahara;Mamoru Nanasato;Toshimi Ikemage;Mitsuaki Isobe
    • Korean Circulation Journal
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    • v.53 no.11
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    • pp.727-743
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    • 2023
  • Although cardiac rehabilitation (CR) has been shown to improve exercise tolerance and prognosis in patients with cardiovascular diseases, there remains low participation in outpatient CR. This may be attributed to the patients' busy schedules and difficulty in visiting the hospital due to distance, cost, avoidance of exercise, and severity of coronary disease. To overcome these challenges, many countries are exploring the possibility of remote CR. Specifically, there is increasing attention on the development of remote CR devices, which allow transmission of vital information to the hospital via a remote CR application linked to a wearable device for telemonitoring by dedicated hospital staff. In addition, remote CR programs can support return to work after hospitalization. Previous studies have demonstrated the effects of remote CR on exercise tolerance. However, the preventive effects of remote CR on cardiac events and mortality remain controversial. Thus, safe and effective remote CR requires exercise risk stratification for each patient, telenursing by skilled staff, and multidisciplinary interventions. Therefore, quality assurance of telenursing and multi-disciplinary interventions will be essential for remote CR. Remote CR may become an important part of cardiac management in the future. However, issues such as cost-effectiveness and insurance coverage still persist.

Analysis of Wind Vorticity and Divergence in the High-latitude Lower Thermosphere: Dependence on the Interplanetary Magnetic Field (IMF) (고위도 하부 열권 바람의 소용돌이도와 발산 분석: 행성간 자기장(IMF)에 대한 의존도)

  • Kwak, Young-Sil;Lee, Jae-Jin;Ahn, Byung-Ho;Hwang, Jung-A;Kim, Khan-Hyuk;Cho, Kyung-Seok
    • Journal of Astronomy and Space Sciences
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    • v.25 no.4
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    • pp.405-414
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    • 2008
  • To better understand the physical processes that control the high-latitude lower thermospheric dynamics, we analyze the divergence and vorticity of the high-latitude neutral wind field in the lower thermosphere during the southern summertime for different IMF conditions. For this study the National Center for Atmospheric Research Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEG CM) is used. The analysis of the large-scale vorticity and divergence provides basic understanding flow configurations to help elucidate the momentum sources that ulti-mately determine the total wind field in the lower polar thermosphere and provides insight into the relative strengths of the different sources of momentum responsible for driving winds. The mean neutral wind pattern in the high-latitude lower thermosphere is dominated by rotational flow, imparted primarily through the ion drag force, rather than by divergent flow, imparted primarily through Joule and solar heating. The difference vorticity, obtained by subtracting values with zero IMF from those with non-zero IMF, in the high-latitude lower thermosphere is much larger than the difference divergence for all IMF conditions, indicating that a larger response of the thermospheric wind system to enhancement in the momentum input generating the rotational motion with elevated IMF than the corresponding energy input generating the divergent motion. the difference vorticity in the high-latitude lower thermosphere depends on the direction of the IMF. The difference vorticity for negative and positive $B_y$ shows positive and negative, respectively, at higher magnetic latitudes than $-70^{\circ}$. For negative $B_z$, the difference vorticities have positive in the dusk sector and negative in the dawn sector. The difference vorticities for positive $B_z$ have opposite sign. Negative IMF $B_z$ has a stronger effect on the vorticity than does positive $B_z$.

A Study on derivation of drought severity-duration-frequency curve through a non-stationary frequency analysis (비정상성 가뭄빈도 해석 기법에 따른 가뭄 심도-지속기간-재현기간 곡선 유도에 관한 연구)

  • Jeong, Minsu;Park, Seo-Yeon;Jang, Ho-Won;Lee, Joo-Heon
    • Journal of Korea Water Resources Association
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    • v.53 no.2
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    • pp.107-119
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    • 2020
  • This study analyzed past drought characteristics based on the observed rainfall data and performed a long-term outlook for future extreme droughts using Representative Concentration Pathways 8.5 (RCP 8.5) climate change scenarios. Standardized Precipitation Index (SPI) used duration of 1, 3, 6, 9 and 12 months, a meteorological drought index, was applied for quantitative drought analysis. A single long-term time series was constructed by combining daily rainfall observation data and RCP scenario. The constructed data was used as SPI input factors for each different duration. For the analysis of meteorological drought observed relatively long-term since 1954 in Korea, 12 rainfall stations were selected and applied 10 general circulation models (GCM) at the same point. In order to analyze drought characteristics according to climate change, trend analysis and clustering were performed. For non-stationary frequency analysis using sampling technique, we adopted the technique DEMC that combines Bayesian-based differential evolution ("DE") and Markov chain Monte Carlo ("MCMC"). A non-stationary drought frequency analysis was used to derive Severity-Duration-Frequency (SDF) curves for the 12 locations. A quantitative outlook for future droughts was carried out by deriving SDF curves with long-term hydrologic data assuming non-stationarity, and by quantitatively identifying potential drought risks. As a result of performing cluster analysis to identify the spatial characteristics, it was analyzed that there is a high risk of drought in the future in Jeonju, Gwangju, Yeosun, Mokpo, and Chupyeongryeong except Jeju corresponding to Zone 1-2, 2, and 3-2. They could be efficiently utilized in future drought management policies.

Assessment of Climate Change Impact on Storage Behavior of Chungju and the Regulation Dams Using SWAT Model (SWAT을 이용한 기후변화가 충주댐 및 조정지댐 저수량에 미치는 영향 평가)

  • Jeong, Hyeon Gyo;Kim, Seong-Joon;Ha, Rim
    • Journal of Korea Water Resources Association
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    • v.46 no.12
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    • pp.1235-1247
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    • 2013
  • This study is to evaluate the climate change impact on future storage behavior of Chungju dam($2,750{\times}10^6m^3$) and the regulation dam($30{\times}10^6m^3$) using SWAT(Soil Water Assessment Tool) model. Using 9 years data (2002~2010), the SWAT was calibrated and validated for streamflow at three locations with 0.73 average Nash-Sutcliffe model Efficiency (NSE) and for two reservoir water levels with 0.86 NSE respectively. For future evaluation, the HadCM3 of GCMs (General Circulation Models) data by scenarios of SRES (Special Report on Emission Scenarios) A2 and B1 of the IPCC (Intergovernmental Panel on Climate Change) were adopted. The monthly temperature and precipitation data (2007~2099) were spatially corrected using 30 years (1977~2006, baseline period) of ground measured data through bias-correction, and temporally downscaled by Change Factor (CF) statistical method. For two periods; 2040s (2031~2050), 2080s (2071~2099), the future annual temperature were predicted to change $+0.9^{\circ}C$ in 2040s and $+4.0^{\circ}C$ in 2080s, and annual precipitation increased 9.6% in 2040s and 20.7% in 2080s respectively. The future watershed evapotranspiration increased up to 15.3% and the soil moisture decreased maximum 2.8% compared to baseline (2002~2010) condition. Under the future dam release condition of 9 years average (2002~2010) for each dam, the yearly dam inflow increased maximum 21.1% for most period except autumn. By the decrease of dam inflow in future autumn, the future dam storage could not recover to the full water level at the end of the year by the present dam release pattern. For the future flood and drought years, the temporal variation of dam storage became more unstable as it needs careful downward and upward management of dam storage respectively. Thus it is necessary to adjust the dam release pattern for climate change adaptation.

Analysis of Climate Change Researches Related to Water Resources in the Korean Peninsula (한반도 수자원분야 기후변화 연구동향 분석)

  • Lee, Jae-Kyoung;Kim, Young-Oh;Kang, Noel
    • Journal of Climate Change Research
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    • v.3 no.1
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    • pp.71-88
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    • 2012
  • The global warming is probably the most significant issue of concern all over the world and according to the report published by the Intergovernmental Panel on Climate Change (IPCC), the average temperature and extent of global warming around the globe have been on the rise and so have the uncertainty for the future. Such effects of global warming have adverse effects on basic foundation of the mankind in numerous ways and water resource is no exception. The researches on water resources assessment for climate change are significant enough to be used as the preliminary data for researches in other fields. In this research, a total of 124 peer-reviewed publications and 57 reports on the subject of research on climate change related to water resources, that has been carried out so far in Korea has been reviewed. The research on climate change in Korea (inclusive of the peer-reviewed articles and reports) has mainly focused on the future projection and assessment. In the fields of hydrometeorology tendency and projection, the analysis has been carried out with focus on surface water, flood, etc. for hydrological variables and precipitation, temperature, etc. for meteorological variables. This can be attributed to the large, seasonal deviation in the amount of rainfall and the difficulty of water resources management, which is why, the analysis and research have been carried out with focus on those variables such as precipitation, temperature, surface water, flood, etc. which are directly related to water resources. The future projection of water resources in Korea may differ from region to region; however, variables such as precipitation, temperature, surface water, etc. have shown a tendency for increase; especially, it has been shown that whereas the number of casualties due to flood or drought decreases, property damage has been shown to increase. Despite the fact that the intensity of rainfall, temperature, and discharge amount are anticipated to rise, appropriate measures to address such vulnerabilities in water resources or management of drainage area of future water resources have not been implemented as yet. Moreover, it has been found that the research results on climate change that have been carried out by different bodies in Korea diverge significantly, which goes to show that many inherent uncertainties exist in the various stage of researches. Regarding the strategy in response to climate change, the voluntary response by an individual or a corporate entity has been found to be inadequate owing to the low level of awareness by the citizens and the weak social infrastructure for responding to climate change. Further, legal or systematic measures such as the governmental campaign on the awareness of climate change or the policy to offer incentives for voluntary reduction of greenhouse gas emissions have been found to be insufficient. Lastly, there has been no case of any research whatsoever on the anticipated effects on the economy brought about by climate change, however, there are a few cases of on-going researches. In order to establish the strategy to prepare for and respond to the anticipated lack of water resources resulting from climate change, there is no doubt that a standardized analysis on the effects on the economy should be carried out first and foremost.

Water shortage assessment by applying future climate change for boryeong dam using SWAT (SWAT을 이용한 기후변화에 따른 보령댐의 물부족 평가)

  • Kim, Won Jin;Jung, Chung Gil;Kim, Jin Uk;Kim, Seong Joon
    • Journal of Korea Water Resources Association
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    • v.51 no.12
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    • pp.1195-1205
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    • 2018
  • In the study, the water shortage of Boryeong Dam watershed ($163.6km^2$) was evaluated under future climate change scenario. The Soil and Water Assessment Tool (SWAT) was used considering future dam release derived from multiple linear regression (MLR) analysis. The SWAT was calibrated and verified by using daily observed dam inflow and storage for 12 years (2005 to 2016) with average Nash-Sutcliffe efficiency of 0.59 and 0.91 respectively. The monthly dam release by 12 years MLR showed coefficient of determination ($R^2$) of above 0.57. Among the 27 RCP 4.5 scenarios and 26 RCP 8.5 scenarios of GCM (General Circulation Model), the RCP 8.5 BCC-CSM1-1-M scenario was selected as future extreme drought scenario by analyzing SPI severity, duration, and the longest dry period. The scenario showed -23.6% change of yearly dam storage, and big changes of -34.0% and -24.1% for spring and winter dam storage during 2037~2047 period comparing with 2007~2016 period. Based on Runs theory of analyzing severity and magnitude, the future frequency of 5 to 10 years increased from 3 in 2007~2016 to 5 in 2037~2046 period. When considering the future shortened water shortage return period and the big decreases of winter and spring dam storage, a new dam operation rule from autumn is necessary for future possible water shortage condition.