• Title/Summary/Keyword: Precipitation trend

Search Result 272, Processing Time 0.03 seconds

Analysis of Spatiotemporal Changes in Groundwater Recharge and Baseflow using SWAT and BFlow Models (SWAT 모형과 BFlow를 이용한 지하수 함양, 기저유출의 시공간적 변화 분석)

  • Lee, Ji Min;Park, Youn Shik;Jung, Younghun;Cho, Jaepil;Yang, Jae Eui;Lee, Gwanjae;Kim, Ki-Sung;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
    • /
    • v.30 no.5
    • /
    • pp.549-558
    • /
    • 2014
  • Occurrence frequency of flood and drought tends to increase in last a few decades, leading to social and economic damage since the abnormality of climate changes is one of the causes for hydrologic facilities by exceedance its designed tolerance. Soil and Water Assessment Tool (SWAT) model was used in the study to estimate temporal variance of groundwater recharge and baseflow. It was limited to consider recession curve coefficients in SWAT model calibration process, thus the recession curve coefficient was estimated by the Baseflow Filter Program (BFLOW) before SWAT model calibration. Precipitation data were estimated for 2014 to 2100 using three models which are GFDL-ESM2G, IPSL-CM5A-LR, and MIROC-ESM with Representative Concentration Pathways (RCP) scenario. SWAT model was calibrated for the Soyang watershed with NSE of 0.83, and $R^2$ of 0.89. The percentage to precipitation of groundwater recharge and baseflow were 27.6% and 17.1% respectively in 2009. Streamflow, groundwater recharge, and baseflow were estimated to be increased with the estimated precipitation data. GFDL-ESM2g model provided the most large precipitation data in the 2025s, and IPSL-CM5A-LR provided the most large precipitation data in the 2055s and 2085s. Overall, groundwater recharge and baseflow displayed similar trend to the estimated precipitation data.

Changes in Localized Heavy Rain that Cause Disasters Due to Climate Crisis - Focusing on Gwangju (기후 위기로 인한 재난을 야기하는 집중호우 변화 - 광주광역시를 중심으로)

  • Kim, Youn-Su;Chang, In-Hong;Song, Kwang-Yoon
    • Journal of Integrative Natural Science
    • /
    • v.14 no.4
    • /
    • pp.162-175
    • /
    • 2021
  • Recently, due to global warming, the average temperature of the earth has risen, and the glaciers in the Antarctic and Arctic melt, leading to a rise in sea level, which is accompanied by powerful natural disasters such as strong typhoons and tsunamis around the world. Accordingly, a precipitation in summer in Korea also increased, and changes in the form of precipitation were showed with the increase. Compared to the past, the frequency of localized heavy rain is increasing, and the damage from flooding and flooding is increasing day by day. In this study, based on the precipitation data measured in hours from May to September from 2016 to 2021 according to the change in the precipitation form, according to the nature of the torrential rain investigated the change in the summer precipitation form. In addition, the trend of localized heavy rain from 2016 to 2021 was confirmed by classifying them into two types: localized heavy rains caused by cyclones and weather front, and by typhoons and large-scale cyclones. Through this, the change in precipitation due to the climate crisis should not be viewed as a single phenomenon, it should be reflected and discussed on our life focused on scientific and technological development, and it should be used as a stepping stone for realizing a humanistic.

Application of the Large-scale Climate Ensemble Simulations to Analysis on Changes of Precipitation Trend Caused by Global Climate Change (기후변화에 따른 강수 특성 변화 분석을 위한 대규모 기후 앙상블 모의자료 적용)

  • Kim, Youngkyu;Son, Minwoo
    • Atmosphere
    • /
    • v.32 no.1
    • /
    • pp.1-15
    • /
    • 2022
  • Recently, Japan's Meteorological Research Institute presented the d4PDF database (Database for Policy Decision-Making for Future Climate Change, d4PDF) through large-scale climate ensemble simulations to overcome uncertainty arising from variability when the general circulation model represents extreme-scale precipitation. In this study, the change of precipitation characteristics between the historical and future climate conditions in the Yongdam-dam basin was analyzed using the d4PDF data. The result shows that annual mean precipitation and seasonal mean precipitation increased by more than 10% in future climate conditions. This study also performed an analysis on the change of the return period rainfall. The annual maximum daily rainfall was extracted for each climatic condition, and the rainfall with each return period was estimated. In this process, we represent the extreme-scale rainfall corresponding to a very long return period without any statistical model and method as the d4PDF provides rainfall data during 3,000 years for historical climate conditions and during 5,400 years for future climate conditions. The rainfall with a 50-year return period under future climate conditions exceeded the rainfall with a 100-year return period under historical climate conditions. Consequently, in future climate conditions, the magnitude of rainfall increased at the same return period and, the return period decreased at the same magnitude of rainfall. In this study, by using the d4PDF data, it was possible to analyze the change in extreme magnitude of rainfall.

On the Characteristics of Globe Temperature Variation Observed at Downtown in Summer Season (하계에 도심지에서 관측된 흑구온도의 특성 분석)

  • Park, Jong-Kil;Jung, Woo-Sik;Kim, Seok-Cheol;Park, Gil-Un
    • Journal of Environmental Science International
    • /
    • v.17 no.8
    • /
    • pp.907-918
    • /
    • 2008
  • In order to monitor the impact of high temperature which is seen frequently with climate change, we investigated the monthly change in globe temperature, air temperature, mean radiant temperature and effective radiant heat flow, because the four well reflect thermal radiation from bio-meteorological aspect. Both globe temperature and air temperature showed an increasing trend every month. Compared to air temperature, globe temperature had a wider range of temperature change and was more influenced by meteorological element such as precipitation. Diurnal trends of air temperature, globe temperature and the difference between their temperature had the lowest value before the sunrise and the highest around $1300{\sim}1500$ LST, showing the typical diurnal trends. Globe temperature and the difference between their temperature had a sharp increase around $1000{\sim}1100$ LST, maintained high value until 1700 LST and then reclined, though varied by month. The difference between globe temperature and air temperature was highly dependent on the amount of precipitation and clouds. The duration in which globe temperature was higher than air temperature was the lowest in July. Therefore the amount of precipitation was the most affecting, followed by the amount of clouds and wind. In order to find out the diurnal trends of temperature in city center and city outskirts, we assumed the roof of a concrete build ing as a city center, and the grass-covered observatory of the Gimhae International Airport as city outskirts. The diurnal trends of temperature in the two sites showed a strong correlation. The highest and lowest temperature also had the same trend.

An Analysis of Historical Precipitation data for Water Resources Planning (수자원 계획을 위한 과거 강수량자료의 분석)

  • 이동률;홍일표
    • Water for future
    • /
    • v.27 no.3
    • /
    • pp.71-82
    • /
    • 1994
  • A statistical characteristics, relations of calendar and water year, and frequencies of precipitaion which are necessary for water resources planning were analyzed with long historical data(1905-1991 years). And the analysis of precipitation of the drought periods in 1967-1968 years was carried out. The study basins are the five major rivers in Korea. As a results of this study, annual precipitation shows an increasing trend but its variation has no statistical significance. The rellations of calendar and water year precipitation is presented, it shows that there are little difference of the total precipitation between them. The annual minimum series of total precipitation for the periods of 3, 6, 9, and 12 months by water year are constructed, and frequency precipitation for each periods using 2-parameter lognormal distribution is presented. The analysis of the precipitation in 1967-1968 years shows in a natural river basins that it would be a moderate drought, if dry seasons(Oct-May) or wet seasons(Jun-Sep) has 75 percents of historical mean precipitation of the same periods. And if it has less than 60 percents of historical mean precipitation, it would be a severe drought.

  • PDF

A Study on Characteristics of Climate Variability and Changes in Weather Indexes in Busan Since 1904 (1904년 이래의 부산 기후 변동성 및 생활기상지수들의 기후변화 특성 연구)

  • Ha-Eun Jeon;Kyung-Ja Ha;Hye-Ryeom Kim
    • Atmosphere
    • /
    • v.33 no.1
    • /
    • pp.1-20
    • /
    • 2023
  • Holding the longest observation data from April 1904, Busan is one of the essential points to understand the climate variability of the Korean Peninsula without missing data since implementing the modern weather observation of the South Korea. Busan is featured by coastal areas and affected by various climate factors and fluctuations. This study aims to investigate climate variability and changes in climatic variables, extremes, and several weather indexes. The statistically significant change points in daily mean rainfall intensity and temperature were found in 1964 and 1965. Based on the change point detection, 117 years were divided into two periods for daily mean rainfall intensity and temperature, respectively. In the long-term temperature analysis of Busan, the increasing trend of the daily maximum temperature during the period of 1965~2021 was larger than the daily mean temperature and the daily minimum temperature. Applying Ensemble Empirical Mode Decomposition, daily maximum temperature is largely affected by the decadal variability compared to the daily mean and minimum temperature. In addition, the trend of daily precipitation intensity from 1964~2021 shows a value of about 0.50 mm day-1, suggesting that the rainfall intensity has increased compared to the preceding period. The results in extremes analysis demonstrate that return values of both extreme temperatures and precipitation show higher values in the latter than in the former period, indicating that the intensity of the current extreme phenomenon increases. For Wet-Bulb Globe Temperature (effective humidity), increasing (decreasing) trend is significant in Busan with the second (third)-largest change among four stations.

Influence of Boreal Summer Intraseasonal Oscillation on Korean Precipitation and its Long-Term Changes (여름철 계절안 진동이 한반도 강수에 미치는 영향 및 장기 변화 특성 연구)

  • Lee, June-Yi;Hsu, Pang-Chi;Moon, Suyeon;Ha, Kyung-Ja
    • Atmosphere
    • /
    • v.27 no.4
    • /
    • pp.435-444
    • /
    • 2017
  • By analyzing Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation (APHRODITE) from May to September for 1951~2007, this study investigates impacts of two dominant boreal summer intraseasonal oscillation (BSISO) modes on precipitation over Monsoon Asia including Korea and long-term change of 10~20-day and 30~60-day ISO over Korea. It is shown that BSISO strongly modulates rainfall variability over the many part of Monsoon Asia including Korea. Korea tends to have more (less) rainfall during the phases 3~5 (7~8) of BSISO1 representing the canonical northward/northeastward propagating 30~60-day ISO and during the phases 6~8 (3~5) of BSISO2 representing the northward/northwestward propagating 10~20-day ISO. It is found that the 10~20-day ISO variability contributes to summer mean rainfall variability more than 30~60-day ISO over Korea. For the 57 years of 1951~2007, the correlation coefficient between the May to September mean precipitation anomaly and standard deviation of 10~20-day (30~60-day) ISO is 0.71 (0.46). It is further noted that there is a significant increasing trend in the 10~20-day and 30~60-day ISO variability in the rainy season during the period of 1951 to 2007.

A Hierarchical Bayesian Modeling of Temporal Trends in Return Levels for Extreme Precipitations (한국지역 집중호우에 대한 반환주기의 베이지안 모형 분석)

  • Kim, Yongku
    • The Korean Journal of Applied Statistics
    • /
    • v.28 no.2
    • /
    • pp.137-149
    • /
    • 2015
  • Flood planning needs to recognize trends for extreme precipitation events. Especially, the r-year return level is a common measure for extreme events. In this paper, we present a nonstationary temporal model for precipitation return levels using a hierarchical Bayesian modeling. For intensity, we model annual maximum daily precipitation measured in Korea with a generalized extreme value (GEV). The temporal dependence among the return levels is incorporated to the model for GEV model parameters and a linear model with autoregressive error terms. We apply the proposed model to precipitation data collected from various stations in Korea from 1973 to 2011.

Long-term Changes in Wintertime Precipitation and Snowfall over Gangwon Province (강원 지역의 장기 겨울철 강수 및 강설 변화의 경향 분석)

  • Baek, Hee-Jeong;Ahn, Kwangdeuk;Joo, Sangwon;Kim, Yoonjae
    • Journal of Climate Change Research
    • /
    • v.8 no.2
    • /
    • pp.109-123
    • /
    • 2017
  • The effects of recent climate change on hydrological systems could affect the Winter Olympic Games (WOG) because the event is dependent on suitable snow and ice conditions to support elite-level competitions. We investigate the long-term variability and change in winter total precipitation (P), snowfall water equivalent (SFE), and ratios of SFE to P during the period 1973/74~2015/16 in Gangwon province. The climatological percentages of SFE relative to winter total precipitation were 71%, 28%, and 44% in Daegwallyeong, Chuncheon, and Gangneung, respectively. The winter total P, SFE, and SFE/P has decreased (but not significantly), although significant increases of winter maximum and minimum temperature were detected at a 95% confidence level. Notably, a significant negative trend of SFE/P at Daegwallyeong in February, the month of the WOG, was attributable to a larger decrease in SFE related to the increases in maximum and minimum temperature. Winter wet-day minimum temperatures were warmer than climatological minimum temperatures averaged over the study period. The 20-year return values of daily maximum P and SFE decreased in Yongdong area. Since the SFE/P decrease with increasing temperature, the probability of rainfall rather than snowfall can increase if global warming continues.

Trend Analysis of Vegetation Changes of Korean Fir (Abies koreana Wilson) in Hallasan and Jirisan Using MODIS Imagery (MODIS 시계열 위성영상을 이용한 한라산과 지리산 구상나무 식생 변동 추세 분석)

  • Minki Choo;Cheolhee Yoo;Jungho Im;Dongjin Cho;Yoojin Kang;Hyunkyung Oh;Jongsung Lee
    • Korean Journal of Remote Sensing
    • /
    • v.39 no.3
    • /
    • pp.325-338
    • /
    • 2023
  • Korean fir (Abies koreana Wilson) is one of the most important environmental indicator tree species for assessing climate change impacts on coniferous forests in the Korean Peninsula. However, due to the nature of alpine and subalpine regions, it is difficult to conduct regular field surveys of Korean fir, which is mainly distributed in regions with altitudes greater than 1,000 m. Therefore, this study analyzed the vegetation change trend of Korean fir using regularly observed remote sensing data. Specifically, normalized difference vegetation index (NDVI) from Moderate Resolution Imaging Spectroradiometer (MODIS), land surface temperature (LST), and precipitation data from Global Precipitation Measurement (GPM) Integrated Multi-satellitE Retrievalsfor GPM from September 2003 to 2020 for Hallasan and Jirisan were used to analyze vegetation changes and their association with environmental variables. We identified a decrease in NDVI in 2020 compared to 2003 for both sites. Based on the NDVI difference maps, areas for healthy vegetation and high mortality of Korean fir were selected. Long-term NDVI time-series analysis demonstrated that both Hallasan and Jirisan had a decrease in NDVI at the high mortality areas (Hallasan: -0.46, Jirisan: -0.43). Furthermore, when analyzing the long-term fluctuations of Korean fir vegetation through the Hodrick-Prescott filter-applied NDVI, LST, and precipitation, the NDVI difference between the Korean fir healthy vegetation and high mortality sitesincreased with the increasing LST and decreasing precipitation in Hallasan. Thissuggests that the increase in LST and the decrease in precipitation contribute to the decline of Korean fir in Hallasan. In contrast, Jirisan confirmed a long-term trend of declining NDVI in the areas of Korean fir mortality but did not find a significant correlation between the changes in NDVI and environmental variables (LST and precipitation). Further analyses of environmental factors, such as soil moisture, insolation, and wind that have been identified to be related to Korean fir habitats in previous studies should be conducted. This study demonstrated the feasibility of using satellite data for long-term monitoring of Korean fir ecosystems and investigating their changes in conjunction with environmental conditions. Thisstudy provided the potential forsatellite-based monitoring to improve our understanding of the ecology of Korean fir.