• 제목/요약/키워드: Climatic Changes

검색결과 319건 처리시간 0.028초

Records of Holocene Environmental Changes in Terrestrial Sedimentary Deposits on King George Island, Antarctica; A Critical Review

  • Tatur A.;Valle R. Del;Barczuk A.;Martinez-Macchiavello J.
    • Ocean and Polar Research
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    • 제26권3호
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    • pp.531-537
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    • 2004
  • In this study we discuss some problems that emerged from paleolimnological and paleontological investigations of terrestrial Holocene ecosystems on King George Island (South Shetland Islands) conducted by an Argentine-Polish research group. Biological and geochemical markers commonly used in standard analytical procedures are considered insufficient in tracing overlapping records of past environmental changes preserved in peat banks, lake sediments and ornithogenic remnants. Records that might be explained by predictable natural events (related to glacio-isostatic uplift of land), roughly predictable events (ecological succession), or unpredictable events (volcanic eruptions or accidental destruction of aquatic moss) may overlap or interfinger one with another providing that signals of regional and/or global climatic changes, are hardly identifiable. A more sophisticated and more selective methods are recommended to do discrimination between records of local and regional/golbal processes in studies on Holocene climatic history of the South Shetland Islands.

Local Climate Mediates Spatial and Temporal Variation in Carabid Beetle Communities on Hyangnobong, Korea

  • Park, Yong Hwan;Jang, Tae Woong;Jeong, Jong Cheol;Chae, Hee Mun;Kim, Jong Kuk
    • Journal of Forest and Environmental Science
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    • 제33권3호
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    • pp.161-171
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    • 2017
  • Global environmental changes have the capacity to make dramatic alterations to floral and faunal composition, and elucidation of the mechanism is important for predicting its outcomes. Studies on global climate change have traditionally focused on statistical summaries within relatively wide scales of spatial and temporal changes, and less attention has been paid to variability in microclimates across spatial and temporal scales. Microclimate is a suite of climatic conditions measured in local areas near the earth's surface. Environmental variables in microclimatic scale can be critical for the ecology of organisms inhabiting there. Here we examine the effect of spatial and temporal changes in microclimates on those of carabid beetle communities in Hyangnobong, Korea. We found that climatic variables and the patterns of annual changes in carabid beetle communities differed among sites even within the single mountain system. Our results indicate the importance of temporal survey of communities at local scales, which is expected to reveal an additional fraction of variation in communities and underlying processes that has been overlooked in studies of global community patterns and changes.

해수면 변동으로 본 한반도 홀로세(Holocene) 기후변화 (Holocene climate characteristics in Korean Peninsula with the special reference to sea level changes)

  • 황상일;윤순옥
    • 한국지형학회지
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    • 제18권4호
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    • pp.235-246
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    • 2011
  • 해안충적평야에서 얻은 연대측정 자료와 미화석 연구 결과 및 퇴적상을 통해 복원된 홀로세 해수면변동 곡선은 기후변화의 내용을 포함하고 있다. 6,000~5,000년 전은 '해진극상기'이며 '기후최적기'로서 중부유럽에서 여름기온은 현재보다 2~3℃ 더 높았다. 당시의 한반도 해수면은 현재보다 0.8~1.0m 더 높았으며, 현재보다 더 온난하였을 것으로 추정된다. 특히 한반도에서는 2,000~1,800년 전에 해수면이 현재보다 1.1~1.3m 더 높은 수준에 도달하였으며, 기후최적기에 버금가는 정도로 온난하였을 가능성이 있다. '서브보레알'에는 중부 유럽의 기온이 현재보다 2~3℃ 더 낮았음에도 불구하고, 이 시기 우리나라의 해수면은 현재보다 높았다. 홀로세 중기 이후 해수면이 가장 낮았던 2,300년 전 경에도 현재와 유사한 고도에 있었다. 이와 같은 사실에서 볼 때, 한반도에서 복원된 해수면변동 곡선은 한랭한 시기의 기후환경을 정확하게 반영하지 않은 것으로 생각된다.

금강유역의 습윤/건조 상태에 대한 경향성 분석 (Trend Analysis of Wetness/Dryness in Geum River Basin)

  • 김주철;이상진;황만하;안정민
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2010년도 학술발표회
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    • pp.1640-1644
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    • 2010
  • In this study the wetness/dryness in Geum river basin are classified by dint of cumulative probability density function of monthly moisture index and the long term changes of them are analyzed based on climatic water balance concept. The drought events in Geum river basin are selected through evaluation of monthly moisture index and the various hydrological properties of them are investigated in detail. Also the trends of time-series of climatic water balance components are examined by Seasonal Kendall test and the variability of hydrological cycle in Geum river basin during the recent decade is inquired. It is judged that the results of this study can be contributed to establishment of the counter plan against the future drought events as the fundamental information.

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Spatio-Temporal Projection of Invasion Using Machine Learning Algorithm-MaxEnt

  • Singye Lhamo;Ugyen Thinley;Ugyen Dorji
    • Journal of Forest and Environmental Science
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    • 제39권2호
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    • pp.105-117
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    • 2023
  • Climate change and invasive alien plant species (IAPs) are having a significant impact on mountain ecosystems. The combination of climate change and socio-economic development is exacerbating the invasion of IAPs, which are a major threat to biodiversity loss and ecosystem functioning. Species distribution modelling has become an important tool in predicting the invasion or suitability probability under climate change based on occurrence data and environmental variables. MaxEnt modelling was applied to predict the current suitable distribution of most noxious weed A. adenophora (Spreng) R. King and H. Robinson and analysed the changes in distribution with the use of current (year 2000) environmental variables and future (year 2050) climatic scenarios consisting of 3 representative concentration pathways (RCP 2.6, RCP 4.5 and RCP 8.5) in Bhutan. Species occurrence data was collected from the region of interest along the road side using GPS handset. The model performance of both current and future climatic scenario was moderate in performance with mean temperature of wettest quarter being the most important variable that contributed in model fit. The study shows that current climatic condition favours the A. adenophora for its invasion and RCP 2.6 climatic scenario would promote aggression of invasion as compared to RCP 4.5 and RCP 8.5 climatic scenarios. This can lead to characterization of the species as preferring moderate change in climatic conditions to be invasive, while extreme conditions can inhibit its invasiveness. This study can serve as reference point for the conservation and management strategies in control of this species and further research.

기상 요인이 보리호위축병(BaYMV) 발생에 미치는 영향 (Effect of Climatic Factors on Disease Incidence of Barley fellow Mosaic Virus (BaYMV))

  • 박종철;서재환;김형무;이귀재;박상래;서득용
    • 한국작물학회지
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    • 제48권3호
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    • pp.156-159
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    • 2003
  • 1. 4개년 조사 기간 중 보리호위축병 발병율은 6.6%-62.5%로 연차간 기상조건에 따라 큰 변이를 나타내었다. 2. 면역혈청학적 검정 결과 보리호위축병의 감염이 확인되었으며, 일부 품종은 BaMMV와의 혼합 감염이 발생하였으나 보리호위축병에 비해 상대적으로 발생이 낮은 경향이었다. 3. 월동전 보리 초기 생육 기간의 기상 조건과 발병율의 변화 조사 결과 평균기온이 바이러스의 감염과 유의성 있는 상관을 나타내었다. 4. 월동기중에는 기상조건과 발병율과는 어떤 요인도 유의성 있는 상관을 나타내지 않았다. 5. 생육재생기 이후의 발병율은 최고기온과 유의성 있는 상관을 나타내어 병징 발현에는 최고기온이 영향을 미치는 것으로 조사되었다.

기상청 기후자료의 균질성 문제 (I) - 관측지점의 이전 (Inhomogeneities in Korean Climate Data (I): Due to Site Relocation)

  • 류상범;김연희;권태헌;박일수
    • 대기
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    • 제16권3호
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    • pp.215-223
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    • 2006
  • Among observational, local-environmental, and large-scale factors causing significant changes in climate records, the site relocations and the replacement of the instruments are well-known nonclimatic factors for the analysis of climatic trends, climatic variability, and for the detection of anthropogenic climate change such as heat-island effect and global warming. Using dataset that were contaminated by these nonclimatic factors can affect seriously the assessment of climatic trends and variability, and the detection of the climatic change signal. In this paper, the inhomogeneities, which have been caused by relocation of the observation site, in the climate data of Korea Meteorological Administration (KMA) were examined using two-phase regression model. The observations of pan evaporation and wind speed are more sensitive to site relocations than those of other meteorological elements, such as daily mean, maximum and minimum temperatures, with regardless to region.

도시기후지도의 작성 -상계 4동을 중심으로- (Urban Climate Mapping - The Case of Sanggye 4-Dong -)

  • 송영배
    • 한국조경학회지
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    • 제29권6호
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    • pp.27-36
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    • 2002
  • The objective of this study is to improve the quality of the atmospheric environment by incorporating the factors of meteorology and urban climate into the field of urban and environmental planning. To this end, we have conducted a study on CLIMATOP and the mapping of urban climate, which are basic data used to analyze changes in climatic factors and the stagnation and accumulation of air pollutants. In particular, we focused on understanding the formation and movement of cold fresh air and its influx into urban areas by measuring and analyzing climatic factors. As a study result, classification criteria far CLIMATOP and a urban climatic map were made. In addition, we analyzed a digital elevation model, climatic data, and isothermal curves. As a result, we identified the corridor through which cold fresh air moves. We also observed that the temperature of the fluxed cold fresh air increased as land use changed. When the results of this study are applied to urban re-development and re-building projects, which require preliminary environmental assessment and environmental impact assessment, the practice proposed by this study is expected to contribute to the natural purification of air pollution activating the movement of cold fresh air and its influx into urban areas.

북한산국립공원의 현존식생과 잠재자연식생 (Actual Vegetation Potential Natural Vegetation of Pukhansan National Park, Mid-western Korea)

  • 이은복
    • The Korean Journal of Ecology
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    • 제20권6호
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    • pp.439-450
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    • 1997
  • The potential natural vegtation of the Pukhansan National Park area, mid-western Korea, was inferred from the actual vegetation. With the phytosociological classification and field surveys, the actual vegetation map of the park area was made on a scale of 1:25, 000, including fourteen communities. By the analyses of the species diversity, the age structure, the human interferences and various informations on vegetation changes, two pathways of late stage succession from Pinus densiflora forests to the climatic climax were suggested. One is from Quercus serrata forests to Q. mongolica forests throughout the mountain and the other, from Q. variabilis or Q. acutissima forests to Carpinus laxiflora forests in lower parts. Considering the vegetation changes, the potential natural vegetation of the park area mainly composed of Q. mongolica, C. laxiflora, P. densiflora and Zelkova serrata forest as the climatic and/or edaphic climax was inferred.

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