• Title/Summary/Keyword: period of climatic change

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The Climate of Korea in the View of the Climatic Year (연후(年候)에서 본 한국(韓國)의 기후(氣候))

  • Kang, Man-Suk
    • Journal of the Korean association of regional geographers
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    • v.3 no.1
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    • pp.1-12
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    • 1997
  • The climatic characteristics of Korea are analized with the data observed from 1972 to 1995 in 66 stations, using the climatic year method expressed by the $K{\ddot{o}}ppen's$ system of climatic classification. The climate of Korea is composed of the six climatic year types : Cfa, Cwa, Cwb, Dfa, Dwa and Dwb type. The Cwa and Dwa type occupy 95% occurrence frequency. The Cwa climatic year type predominates in the greater part of the Southern Area, the east slopes of the Taebaek Range and Cheju-do, the Dwa type does in Yongso Area and the northeastern part of Kyonggi Province. and the Cfa type does in Ullung-do. Such dominant climatic year regions become the stable climatic regions, while the regions where the various climatic types appear become the unstable climatic regions which are distributed in the northern part of the Southern Area and in the southern part of the Central Area owing to the shifts of the border between C type and D type. The border between C and D type is located in the Central Inland Area in the first half of the 1990's which the Cwa type predominates most. On the other hand the border is located in the middle part of the Southern Area in the first half of the 1980's which the Dwa type prevails most. Therefore the extents of the climatic year regions vary each year. In the interannual change of the main climatic year types, the Cwa type shows the increasing trend, while the Cfa and Dwa type reflets the decreasing tendency. The extending trend of the Cwa climatic year region appears during the period of the first half of the 1970's and the period between the latter half of the 1980's and the first half of the 1990's centering around the Southern Area. The Dwa climatic year region which was predominant in the Central Area in the first half of the 1980's has been reduced up till the recent years.

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Change of Climatic Productivity Index for Rice under Recent Climate Change in Korea (최근 8-9월의 기상특징과 기후생산력지수의 변화)

  • Shim, Kyo-Moon;Kim, Yong-Seok;Jung, Myung-Pyo;Choi, In-Tae
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.16 no.4
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    • pp.384-388
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    • 2014
  • Air temperature has increased, while sunshine hour has decreased during the grain filling period of most rice cultivars (August to September) during the past 12 years from 2001 through 2012 in Korea. Climatic Productivity Index (CPI) has fallen because of the decreased sunshine hour and increased air temperature during the grain filling period, and the degree of reduction was greater with earlier heading. For stable rice production, we will need to delay the heading of rice as a cultivation measure against the future climatic trend. Grain yield showed no significant trend for past 12 years. However, the year to year change in grain yield showed a similliar pattern with that of CPI. Especially, a linear function relating rice yield to CPI explained approximately 63% of variation in grain yield with the heading date of August $11^{th}$ period.

Modeling the Present Probability of Urban Woody Plants in the face of Climate Change (기후변화에 따른 도시 수종의 기후 적합성 평가모델 - 서울시를 대상으로 -)

  • Kim, Yoon-Jung;Lee, Dong-Kun;Park, Chan
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.16 no.1
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    • pp.159-170
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    • 2013
  • The effect of climate change on urban woody plants remains difficult to predict in urban areas. Depending on its tolerances, a plant species may stay and survive or stay with slowly declining remnant populations under a changing climate. To predict those vulnerabilities on urban woody plants, this study suggests a basic bioclimatic envelop model of heat requirements, cold tolerance, chilling requirements and moisture requirements that are well documented as the 'climatic niche'. Each component of the 'climatic niche' is measured by the warmth index, the absolute minimum temperature, the number of chilling weeks and the water balance. Regarding the utility of the developed model, the selected urban plant's present probabilities are suggested in the future climate of Seoul. Both Korea and Japan's thermal thresholds are considered for a plant's optimal climatic niche. By considering the thermal thresholds of these two regions for the same species, the different responses observed will reflect the plant's 'hardening' process in a rising climate. The model illustrated that the subpolar plants Taxus cuspidata and Ulmus davidiana var. japonica are predicted to have low suitability in Seoul. The temperate plants Zelkova serrata and Pinus densiflora, which have a broad climatic niche, exhibited the highest present probability in the future. The subtropical plants Camellia japonica and Castanopsis cuspidata var. sieboldii may exhibit a modest growth pattern in the late 21C's future climatic period when an appropriate frost management scheme is offered. The model can be used to hypothesize how urban ecosystems could change over time. Moreover, the developed model can be used to establish selection guidelines for urban plants with high levels of climatic adaptability.

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

  • Hwang, Sangill;Yoon, Soon-Ock
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.4
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    • pp.235-246
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    • 2011
  • Sea level fluctuations during the Holocene reconstructed by the results of age dating, microfossils researches and sedimentary facies from coastal alluvial plains contain the valuable informations on climatic changes. The sea level during 'maximum phase of transgression' during 6,000~5,000 yr BP was slightly higher than the present by approximately 0.8~1.0 m and the summer temperature conditions seemed to be higher than those of the present by 2~3℃ in the Central Europe when the period of 'Climatic Optimum' might be dominant. The sea level in Korean Peninsula was assumed by 0.8~1.0 m higher at that time compared to the present and climate seemed to be warmer. At 2,000~1,800 yr BP in Korean Peninsula, the sea level reached the higher stand than the present by approximately 1.1~1.3 m and the climatic conditions might be warm similar to the period of 'Climatic Optimum'. Although the temperature in the Central Europe during the period of 'Subboreal' was about 2~3℃ cooler, it is supposed that the sea level in Korean Peninsula was relatively higher than the present. The sea level at 2,300 yr BP might be similar to that of the present, which was the lowest level since the mid-Holocene. From the fact, climatic environment during the cold period might not be reflected exactly in the sea level.

Humus Analysis for the Geomorphic Development and Climatic Environment Change of Alluvial Plain in Hampyeongcheon Basin during the Late Holocene (휴무스분석을 이용한 함평천 유역의 홀로세 후기 충적평야의 지형발달과 기후환경변화)

  • Jung, Hea-Kyung;Kim, Cheong-Bin
    • Journal of the Korean earth science society
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    • v.33 no.4
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    • pp.320-328
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    • 2012
  • To investigate geomorphic development of alluvial plains and climatic environment change during the late Holocene carbon dating, soil organic carbon analysis and humus analysis of sediments from alluvial plain of Hampyeongcheon basin were performed. The lowest peat layer was formed under warm and humid climates, which is considered to correspond to the Atlantic period in the Holocene. Yellowish brown sandy clay layer was deposited in the natural levee, which we think were deposited in the generally warm and dry climates. The carbon dating age is 1,879-1,532 BC, and this period correspond to the Sub-boreal period in the Holocene. Light brown clay layer is assumed to have been deposited in transitional environment from the natural levee to the back marsh. The climatic environment was warm and humid, which is considered as transitional period from the Sub-boreal to the Sub-Atlantic in the Holocene. Light yellowish brown and light brown clay layer of the upper part are regarded as sediments of the back marsh. Light yellowish brown clay layer was deposited in the cold and dry climates, which is considered to correspond to the Sub-Atlantic period in the Holocene. Light brown clay layer was deposited in the warm and dry climates. The carbon dating age is 211-427 AD, this period corresponds to the Post Roman Warm Period in the Holocene.

The Influence of Change in Climatic Environment during the Song-Yuan Dynasty Had on the Development of Medical Science and Disease Emergence (송원(宋元)시대 기후환경변화가 질병과 의학발전에 미친 영향)

  • Kim, Ji-Soo;Jung, Ji-Hun;Park, Hae-Mo
    • The Journal of Korean Medical History
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    • v.31 no.2
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    • pp.53-62
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    • 2018
  • It is known that the development of medical science is influenced by various social environmental factors. Historically, Chinese Medicine developed the most during the Song Yuan dynasty, and the reason for this was known to be due to socio-political factors. According to recent studies, however, this period also had severe changes in climate and environment. Therefore, this study was conducted under the premise that this change in climate and environment influenced medical development. When looking at the coldness of the 11th~12th century and data indicating warming before and after this period, the Song Yuan dynasty went through drastic periods of climate change. Therefore, diseases related to heat such as bubonic plague, measles, and malaria were common. Furthermore, due to occasional wars during the Song Yuan dynasty, social unrest was aggravated and infectious diseases spread due to land development and environmental pollution. As the health of people were threatened due to these factors, the printing and distribution of medical text were encouraged, and during this process, the great 4 doctors of Jin-Yuan appeared. The reason why they studied cures for infectious diseases due to heat was related to climatic environment change. The development in medical science is closely related to socio-political factors, however the change in climatic environments are inevitably related to disease emergence as well. Therefore, it should always be taken into consideration as an important factor that promotes development in medical science.

Climate and Land use Changes Impacts on Hydrology in a Rural Small Watershed (장래 기후변화와 토지이용 변화에 따른 농촌소유역의 수문 영향 분석)

  • Kim, Hak-Kwan;Kang, Moon-Seong;Lee, Eun-Jeong;Park, Seung-Woo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.53 no.6
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    • pp.75-84
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    • 2011
  • The objective of this study is to evaluate the hydrologic impacts of climate and land use changes in a rural small watershed. HadCM3 (Hadley Centre Coupled Model, ver.3) A2 scenario and LARS-WG (Long Ashton Research Station - Weather Generator) were used to generate future climatic data. Future land use data were also generated by the CA-Markov (Cellular Automata-Markov) method. The Soil and Water Assessment Tool (SWAT) model was used to evaluate hydrologic impacts. The SWAT model was calibrated and validated with stream flow measured at the Baran watershed in Korea. The SWAT model simulation results agreed well with observed values during the calibration and validation periods. In this study, hydrologic impacts were analyzed according to three scenarios: future climate change (Scenario I), future land use change (Scenario II), and both future climate and land use changes (Scenario III). For Scenario I, the comparison results between a 30-year baseline period (1997~2004) and a future 30-year period (2011~2040) indicated that the total runoff, surface runoff, lateral subsurface runoff, groundwater discharge, and evapotranspiration increased as precipitation and temperature for the future 30-year period increased. The monthly variation analysis results showed that the monthly runoff for all months except September increased compared to the baseline period. For Scenario II, both the total and surface runoff increased as the built-up area, including the impervious surface, increased, while the groundwater discharge and evapotranspiration decreased. The monthly variation analysis results indicated that the total runoff increased in the summer season, when the precipitation was concentrated. In Scenario III, the results showed a similar trend to that of Scenario II. The monthly runoff for all months except October increased compared to the baseline period.

Evaluation of Agro-Climatic Indices under Climate Change (기후변화에 따른 농업기후지수의 평가)

  • Shim, Kyo-Moon;Kim, Gun-Yeob;Roh, Kee-An;Jeong, Hyun-Cheol;Lee, Deog-Bae
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.10 no.4
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    • pp.113-120
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    • 2008
  • The increase in average air temperature over the past 100 years in northern Asia including Korea is the greatest (about ${1.5}^{\circ}C$) among the various regions of the world. Considering a further warming projected by the IPCC, fluctuations of agro-climatic indices under climate change must precede an evaluation of vulnerability. The purpose of this study is to analyze how climate changes represented by global warming have altered agro-climatic indices in Korea over various time scales. Drought index during the rice-transplanting period of 15 May to 5 June has changed toward the favorable with recently increased precipitation in the Taebaek Alpine and Semi-Alpine Zone, and Yeongnam Basin and Inland Zone. The frequency of low temperature occurrence below $13^{\circ}C$ during the rice transplanting has decreased, while climatic production index (CPI) has fallen because of the decreased sunshine hour and increased temperature during the rice ripening period. We therefore concluded that the recent change of climate conditions was against the rice productivity in Korea.

The Relationship between Climatic and Oceanographic Factors and Laver Aquaculture Production (기후 및 해양 요인과 김 생산량과의 관계에 관한 연구)

  • Kim, Do-Hoon
    • The Journal of Fisheries Business Administration
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    • v.44 no.3
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    • pp.77-84
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    • 2013
  • While some steps in laver aquaculture production can be controlled artificially to a certain extent, the culturing process is largely affected by natural factors, such as the characteristics of seawater, climatic and oceanographic conditions, etc. This study aims to find a direct relationship between climatic and oceanographic factors (water temperature, air temperature, salinity, rainfall, sunshine duration and wind speed) and laver aquaculture production in Wando region, the biggest aquaculture production area of laver, located in the southwest coast of Korea using a multiple regression analysis. Despite the small sample size of a dependent variable, the goodness of model fit appeared acceptable. In addition, the R-squared value was 0.951, which means that the variables were very explanatory. Model results indicated that duration of sunshine, temperature, and rainfall during the farming period from the end of September to the end of April would be important factors affecting significantly to the laver aquaculture production.

Evaluation of Agro-Climatic Index Using Multi-Model Ensemble Downscaled Climate Prediction of CMIP5 (상세화된 CMIP5 기후변화전망의 다중모델앙상블 접근에 의한 농업기후지수 평가)

  • Chung, Uran;Cho, Jaepil;Lee, Eun-Jeong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.2
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    • pp.108-125
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    • 2015
  • The agro-climatic index is one of the ways to assess the climate resources of particular agricultural areas on the prospect of agricultural production; it can be a key indicator of agricultural productivity by providing the basic information required for the implementation of different and various farming techniques and practicalities to estimate the growth and yield of crops from the climate resources such as air temperature, solar radiation, and precipitation. However, the agro-climate index can always be changed since the index is not the absolute. Recently, many studies which consider uncertainty of future climate change have been actively conducted using multi-model ensemble (MME) approach by developing and improving dynamic and statistical downscaling of Global Climate Model (GCM) output. In this study, the agro-climatic index of Korean Peninsula, such as growing degree day based on $5^{\circ}C$, plant period based on $5^{\circ}C$, crop period based on $10^{\circ}C$, and frost free day were calculated for assessment of the spatio-temporal variations and uncertainties of the indices according to climate change; the downscaled historical (1976-2005) and near future (2011-2040) RCP climate sceneries of AR5 were applied to the calculation of the index. The result showed four agro-climatic indices calculated by nine individual GCMs as well as MME agreed with agro-climatic indices which were calculated by the observed data. It was confirmed that MME, as well as each individual GCM emulated well on past climate in the four major Rivers of South Korea (Han, Nakdong, Geum, and Seumjin and Yeoungsan). However, spatial downscaling still needs further improvement since the agro-climatic indices of some individual GCMs showed different variations with the observed indices at the change of spatial distribution of the four Rivers. The four agro-climatic indices of the Korean Peninsula were expected to increase in nine individual GCMs and MME in future climate scenarios. The differences and uncertainties of the agro-climatic indices have not been reduced on the unlimited coupling of multi-model ensembles. Further research is still required although the differences started to improve when combining of three or four individual GCMs in the study. The agro-climatic indices which were derived and evaluated in the study will be the baseline for the assessment of agro-climatic abnormal indices and agro-productivity indices of the next research work.