• Title/Summary/Keyword: Climate changes

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Changes in the Spawning Ground Environment of the Common Squid, Todarodes pacificus due to Climate Change (기후변화에 따른 살오징어(Todarodes pacificus) 산란장 환경 변화)

  • Kim, Yoon-ha;Jung, Hae Kun;Lee, Chung Il
    • Ocean and Polar Research
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    • v.40 no.3
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    • pp.127-143
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    • 2018
  • This study analyzed the influence of climate change on the spawning ground area of the common squid, Todarodes pacificus. To estimate long term changes in the area of the spawning ground of the common squid, water temperature at 50 m deep that can be inferred from sea surface temperature (SST) based on both NOAA/AVHRR (1981.07-2002.12) and MODIS/AQUA (2003.01-2009.12) ocean color data was analyzed. In addition, five climate indices, Arctic Oscillation Index (AO), Siberian High Index (SH), Aleutian Low Pressure Index (ALP), East Asia Winter Monsoon Index (EAWM) and Pacific Decadal Oscillation (PDO) which are the main indicators of climate changes in the northwestern Pacific were used to study the relationship between the magnitude of the estimated spawning ground and climate indices. The area of the estimated spawning ground was highly correlated with the total catch of common squid throughout four decades. The area of the estimated spawning ground was negatively correlated with SH and EAWM. Especially, PDO was negatively correlated with the area of the spawning ground in the northwestern Pacific (r = -0.39) and in the southern part of the East Sea (r = -0.38). There was a positive relationship between the AO and the area of the spawning ground in the northwestern Pacific (r = 0.46) as well as in the southern part of the East Sea (r = 0.32). Temporally, the area of the winter spawning ground in the southern part of the East Sea in the 1980s was smaller than those areas in the 1990s and 2000s, because the area was disconnected with the western coastal spawning ground of Japan in the 1980s, while the area had been made wider and more continuous from the Korea strait to the western coastal water of Honshu in the 1990s and 2000s.

Prospect of Climate Changes for the Mid and Late 21st Century Using RegCM4.0 over CORDEX II East Asian Region (RegCM4.0을 활용한 CORDEX II 동아시아 지역의 21C 중·후반 기후 변화 전망)

  • Kim, Tae-Jun;Suh, Myoung-Seok;Chang, Eun-Chul
    • Atmosphere
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    • v.29 no.2
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    • pp.165-181
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    • 2019
  • In this study, the regional climate model, RegCM4.0 (25 km), with the HadGEM2-AO data as boundary conditions, was used to simulate the mean climate changes in the mid and late 21st century for CORDEX Phase 2 East Asian region. 122 years (1979~2100) of simulation were performed, and RCP 4.5 and RCP 8.5 were used for the simulation of future climate. In the mid-21st century, the temperature is expected to increase by about 0.5 to $3.0^{\circ}C$ in all regions of East Asia, regardless of season and scenario. The increase in temperature is greater in summer and winter, especially in the northern part of simulation domain. Interannual variability (IAV) is expected to decrease by 25% in summer for RCP 8.5, while it is expected to increase by more than 30% in autumn for both scenarios. Regardless of the scenario, the precipitation in South Korea is expected to increase in late June but decrease in mid-July, with an increase in precipitation greater than $100mm\;day^{-1}$. In RCP 4.5 of the late 21st century, relatively uniform temperature increase ($1.0{\sim}2.5^{\circ}C$) is expected throughout the continent, while RCP 8.5 shows a very diverse increase ($3.0{\sim}6.0^{\circ}C$) depending on season and geographical location. In addition, the IAV of temperature is expected to decrease by more than 35% in both scenarios in the summer. In most of the Northwest Pacific region, precipitation is expected to decrease in all seasons except for the summer, but in South Korea, it is projected to increase by about 10% in all seasons except autumn.

Assessment of Climate Change Impact on Flow Regime and Physical Habitat for Fish (기후변화가 하천 유황과 어류 물리서식처에 미치는 영향 평가)

  • Hong, Il;Kim, Ji Sung;Kim, Kyu Ho;Jeon, Ho Seong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.1
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    • pp.33-44
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    • 2019
  • Due to the recent climate change realization (timing, rainfall pattern changes), the flow regime is changing according to the watershed. The long-term change of flow regime is causing a significant change in structure and function of aquatic ecosystems. However, there is no analysis from the viewpoint of the aquatic ecosystem including flow rate alteration and ecological characteristics as well as the climate change connection in Korea yet. Therefore, We quantitatively assessed the impact of present-future flow regime alteration due to climate change on the Pseudopungtungia nigra habitat in the Mankyung river and floodplain area. As a result, it was confirmed that extreme hydrological conditions such as flood and drought are intensified in the future than the present. Especially, the changes of flow regime characteristics were clarified by comparing and analyzing the magnitude, frequency, duration, rate of change, and by linking flow regime characteristics with physical habitat analysis, it could be suggested that climate change would significantly increase the risk of future ecological changes.

Future Runoff Characteristics of Ganwol Estuary Reservoir Watershed Based on SSP Scenarios (SSP 기후변화 시나리오에 따른 간월호 유역의 미래 유출특성 변화)

  • Kim, Sinae;Kim, Donghee;Kim, Seokhyeon;Hwang, Soonho;Kang, Moon-Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.65 no.5
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    • pp.25-35
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    • 2023
  • The estuary reservoir is a major source of agricultural water in Korea; for effective and sustainable water resource management of the estuary reservoir, it is crucial to comprehensively consider various water resource factors, including water supply, flood, and pollutant management, and analyze future runoff changes in consideration of environmental changes such as climate change. The objective of this study is to estimate the impact of future climate change on the runoff characteristics of an estuary reservoir watershed. Climate data on future Shared Socioeconomic Pathway (SSP) scenarios were derived from two Global Climate Models (GCMs) of the Coupled Model Intercomparison Project phase 6 (CMIP6). The Hydrological Simulation Program-Fortran (HSPF) was used to simulate past and future long-term runoff of the Ganwol estuary reservoir watershed. The findings showed that as the impact of climate change intensified, the average annual runoff in the future period was higher in the order of SSP5, SSP3, SSP1, and SSP2, and the ratio of runoff in July decreased while the ratio of runoff in October increased. Moreover, in terms of river flow regime, the SSP2 scenario was found to be the most advantageous and the SSP3 scenario was the most disadvantageous. The findings of this study can be used as basic data for developing sustainable water resource management plans and can be applied to estuary reservoir models to predict future environmental changes in estuary reservoirs.

Analysis of Phenological Changes by Phenocams on Some Major Species Distributed in Wetland and Forest Ecosystems in Korea (Phenocam을 활용한 국내 습지 및 산림생태계 대표 수종의 계절적 변화 분석)

  • Minki Hong;Hyohyemi Lee;Jeong-Soo Park
    • Ecology and Resilient Infrastructure
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    • v.10 no.4
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    • pp.226-236
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    • 2023
  • As climate change intensifies, the importance of studying plant phenology has increased, leading to a surge in research employing automated video recording devices like Phenocams. In this study, using the Phenocams operated by the National Institute of Ecology, we examined the trends in plant phenological changes across diverse ecosystem types in South Korea and analyzed their correlations with climate factors. The patterns of plant phenological changes varied by region and tree species. Pinus thunbergii and Pinus densiflora typically show an overall increase in their growth period, positively correlating with temperatures and precipitation during winter. However, uniquely, for Abies koreana on Hallasan Mt., a higher amount of precipitation in August leads to an earlier end of season (eos), and the correlation analysis with the recent phenomenon of dying A. Koreana seems necessary. beyond the analysis, solutions for handling missing data issues during the data collection process were proposed. Furthermore, to expand future research scope and encompass diverse ecosystem types, a suggestion to combine Phenocam research with satellite observations was presented.

Relationship Between Climate Change and Total Factor Productivity (기후변화와 국가별 총요소생산성의 관계)

  • Choi, Young Jun;Park, Hyun Yong
    • Environmental and Resource Economics Review
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    • v.24 no.2
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    • pp.343-363
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    • 2015
  • This study is to analyze the effects of climate change on national total factor productivity. Changes in temperature and rainfalls which are the representative climate variables are used as main factors to measure climate change. Not only average values of the variables but those highest values are used as independent variables in the model, in order to consider the characteristic pattern of recent climate change, the high volatilities. The OLS results are corresponding to previous literature that average temperature has a negative relationship with productivities while average rainfalls have a positive relationship. However, the results of panel analysis contradict the argument of the negative relationship between average temperature and productivities since human beings can adapt the climate change. Therefore adaptation capacity is important to forecast the effects of climate changes on economies.

An Uncertainty Assessment of AOGCM and Future Projection over East Asia (동아시아 지역의 AOGCM 불확실성 평가 및 미래기후전망)

  • Kim, Min-Ji;Shin, Jin-Ho;Lee, Hyo-Shin;Kwon, Won-Tae
    • Atmosphere
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    • v.18 no.4
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    • pp.507-524
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    • 2008
  • In this paper, future climate changes over East Asia($20^{\circ}{\sim}50^{\circ}N$, $100^{\circ}{\sim}150^{\circ}E$) are projected by anthropogenic forcing of greenhouse gases and aerosols using coupled atmosphere-ocean general circulation model (AOGCM) simulations based on Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) B1, A1B and A2 scenarios. Before projection future climate, model performance is assessed by the $20^{th}$ Century (20C3M) experiment with bias, root Mean Square Error (RMSE), ratio of standard deviation, Taylor diagram analysis. The result of examination of the seasonal uncertainty of T2m and PCP shows that cold bias, lowered than that of observation, of T2m and wet bias, larger than that of observation, of PCP are found over East Asia. The largest wet bias is found in winter and the largest cold bias is found in summer. The RMSE of temperature in the annual mean increases and this trend happens in winter, too. That is, higher resolution model shows generally better performances in simulation T2m and PCP. Based on IPCC SRES scenarios, East Asia will experience warmer and wetter climate in the coming $21^{st}$ century. It is predict the T2m increase in East Asia is larger than global mean temperature. As the latitude goes high, the warming over the continents of East Asia showed much more increase than that over the ocean. An enhanced land-sea contrast is proposed as a possible mechanism of the intensified Asian summer monsoon. But, the inter-model variability in PCP changes is large.

Review of the Role of Land Surface in Global Climate Change (기후변화에서 지표환경의 역할에 대한 고찰)

  • Kim, Seong-Joong
    • The Korean Journal of Quaternary Research
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    • v.23 no.1
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    • pp.42-53
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    • 2009
  • In response to the abrupt climate change in recent years, atmosphere, ocean and cryosphere are reported to be altered. In addition to these changes, the land surface is also gradually changing and its impact on the global climate may not be negligible. The land surface change impacts the global climate via two ways, the biogeochemical and biophysical feedbacks. The biogeochemcial change in the land surface modifies the atmospheric trace-gas concentrations through a change in photo synthesis, while biophycal changes of the land surface alters the surface albedo, which influences the amount of the short wave radiative heat fluxes. There are many examples in the past that the change in land surface greatly influences the global climate change. The recent IPCC report has suggested that the climate change will occur rather abrubtly in the near future. In order to predict the future climate accurately, the impact of the land surface change is fully considered.

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Evaluation of Climatological Mean Surface Winds over Korean Waters Simulated by CORDEX-EA Regional Climate Models (CORDEX-EA 지역기후모형이 모사한 한반도 주변해 기후평균 표층 바람 평가)

  • Choi, Wonkeun;Shin, Ho-Jeong;Jang, Chan Joo
    • Atmosphere
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    • v.29 no.2
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    • pp.115-129
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    • 2019
  • Surface winds over the ocean influence not only the climate change through air-sea interactions but the coastal erosion through the changes in wave height and direction. Thus, demands on a reliable projection of future changes in surface winds have been increasing in various fields. For the future projections, climate models have been widely used and, as a priori, their simulations of surface wind are required to be evaluated. In this study, we evaluate the climatological mean surface winds over the Korean Waters simulated by five regional climate models participating in Coordinated Regional Climate Downscaling Experiment (CORDEX) for East Asia (EA), an international regional climate model inter-comparison project. Compared with the ERA-interim reanalysis data, the CORDEX-EA models, except for HadGEM3-RA, produce stronger wind both in summer and winter. The HadGEM3-RA underestimates the wind speed and inadequately simulate the spatial distribution especially in summer. This summer wind error appears to be coincident with mean sea-level pressure in the North Pacific. For wind direction, all of the CORDEX-EA models simulate the well-known seasonal reversal of surface wind similar to the ERA-interim. Our results suggest that especially in summer, large-scale atmospheric circulation, downscaled by regional models with spectral nudging, significantly affect the regional surface wind on its pattern and strength.

Estimating potential range shift of some wild bees in response to climate change scenarios in northwestern regions of Iran

  • Rahimi, Ehsan;Barghjelveh, Shahindokht;Dong, Pinliang
    • Journal of Ecology and Environment
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    • v.45 no.3
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    • pp.130-142
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    • 2021
  • Background: Climate change is occurring rapidly around the world, and is predicted to have a large impact on biodiversity. Various studies have shown that climate change can alter the geographical distribution of wild bees. As climate change affects the species distribution and causes range shift, the degree of range shift and the quality of the habitats are becoming more important for securing the species diversity. In addition, those pollinator insects are contributing not only to shaping the natural ecosystem but also to increased crop production. The distributional and habitat quality changes of wild bees are of utmost importance in the climate change era. This study aims to investigate the impact of climate change on distributional and habitat quality changes of five wild bees in northwestern regions of Iran under two representative concentration pathway scenarios (RCP 4.5 and RCP 8.5). We used species distribution models to predict the potential range shift of these species in the year 2070. Result: The effects of climate change on different species are different, and the increase in temperature mainly expands the distribution ranges of wild bees, except for one species that is estimated to have a reduced potential range. Therefore, the increase in temperature would force wild bees to shift to higher latitudes. There was also significant uncertainty in the use of different models and the number of environmental layers employed in the modeling of habitat suitability. Conclusion: The increase in temperature caused the expansion of species distribution and wider areas would be available to the studied species in the future. However, not all of this possible range may include high-quality habitats, and wild bees may limit their niche to suitable habitats. On the other hand, the movement of species to higher latitudes will cause a mismatch between farms and suitable areas for wild bees, and as a result, farmers will face a shortage of pollination from wild bees. We suggest that farmers in these areas be aware of the effects of climate change on agricultural production and consider the use of managed bees in the future.