• Title/Summary/Keyword: recent change

검색결과 2,453건 처리시간 0.026초

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

  • 김성중
    • 한국제4기학회지
    • /
    • 제23권1호
    • /
    • pp.42-53
    • /
    • 2009
  • 최근 급격한 온실가스 증가에 기인하여 대기와 해양 그리고 빙권의 변화가 나타나고 또한 기온과 수분의 함량 변화에 따라서 지표 환경도 서서히 변하기 시작하는 것으로 보고되고 있다. 지표환경의 반응은 생지화학적 반응과 생물리학적 반응으로 구분 할 수 있는데, 생지화학적 반응은 기후변화에 따른 광합성이나 이와 유사한 지표환경의 변화 그리고 이에 따른 화학적인 피드백을 지칭하며 이는 대기의 온실가스 농도를 변화 시키는 역할을 한다. 생물리학적 반응은 기후변화에 따라 식생의 분포가 변하게 되고 이에 따른 태양에너지의 입사율 변화 등과 같은 물리적 반응을 나타낸다. 과거 기후변화역사에도 식생의 변화가 기후변화에 미치는 영향이 매우 컸던 경우가 있었고, 앞으로의 기후변화는 거대하고 급격하게 일어날 것으로 예측되기 때문에, 미래 기후변화의 정확한 예측을 위해서는 지표환경변화의 물리 화학적 변화를 이해하고 예측 모형에 정확히 포함시킬 필요가 있다.

  • PDF

최근 동계작물의 파종기간 동안 기후변화 특징 (Characteristics of Climate Change in Sowing Period of Winter Crops)

  • 심교문;김용석;정명표;최인태
    • 한국기후변화학회지
    • /
    • 제6권3호
    • /
    • pp.203-208
    • /
    • 2015
  • This study was conducted to provide the agricultural climatological basic data for the reset of sowing period of the winter crop on the double cropping system with rice. During the past 30 years from 1981 to 2010, mean air temperature has risen by $0.45^{\circ}C$ per 10 years (with statistical significance), while precipitation has decreased by 6.74 mm per 10 years and the numbers of days for precipitation has reduced by 0.23 days per 10 years (with no statistical significance) in the sowing period ($1^{st}$ Oct. to $5^{th}$ Nov.) of winter crop. It was analyzed that double cropping system of rice and winter crops need to be reset in the way of delaying the sowing time of winter crops, because rising trend of temperature was clear while variability of precipitation was great and the trend was not clear in the sowing period of winter crops. We have also analyzed the meteorological features of the sowing period of winter crops in 2014, and found that mean air temperature in 2014 was higher than that in normal years (similar to recent temperature change feature) while precipitation in 2014 was much more frequent than that in normal years (unlike recent precipitation features). Such tendency in 2014 made the sowing of winter crops difficult because mechanical sowing could not be worked in flooded paddy fields. Heavy rain in October 2014 was also analyzed as a rare phenomenon.

기후변화에 대한 식물의 생태적 반응: 연구동향과 한국에서의 적용가능성 (Ecological Responses of Plants to Climate Change: Research Trends and Its Applicability in Korea)

  • 강혜순
    • 생태와환경
    • /
    • 제46권3호
    • /
    • pp.319-331
    • /
    • 2013
  • Recent climate change, which is mostly ascribed to anthropogenic activities, is believed to be a major factor leading to biodiversity decreases and ecosystem service deteriorations. I have reviewed recent studies on climate change effects for many ecological processes involved with plants, in order to improve our understanding of the nature of ecological complexity. Plants in general have better growth and productivity under high levels of $CO_2$, although the long term effects of such $CO_2$ fertilizers are still controversial. Over the last 30 years, the Earth has been greening, particularly at higher latitudes of the Northern Hemisphere, perhaps due to a relaxation of climatic constraints. Human appropriation of net primary productivity (NPP), which corresponds up to 1/3 of global NPP, is ultimately responsible for climate change and biodiversity decreases. Climate change causes phenological variations in plants, especially in regards to spring flowering and fall leaf coloring. Many plants migrate polewards and towards higher altitudes to seek more appropriate climates. On the other hand, tree mortality and population declines have recently been reported in many continents. Landscape disturbance not only hinders the plant migration, but also makes it difficult to predict the plants' potential habitats. Plant and animal population declines, as well as local extinctions, are largely due to the disruption of species interactions through temporal mismatching. Temperature and $CO_2$ increase rates in Korea are higher than global means. The degree of landscape disturbances is also relatively high. Furthermore, long-term data on individual species responses and species interactions are lacking or quite limited in Korea. This review emphasizes the complex nature of species responses to climate change at both global and local scales. In order to keep pace with the direction and speed of climate change, it is urgently necessary to observe and analyze the patterns of phenology, migration, and trophic interactions of plants and animals in Korea's landscape.

기후변화로 인한 청미천유역의 기상학적 위협요인 규명 (Identification of Meteorological Threats by Climate Change in the Cheongmicheon Basin)

  • 이철응;김상욱
    • 산업기술연구
    • /
    • 제35권
    • /
    • pp.23-30
    • /
    • 2015
  • In recent, the various methods to predict the hydrological impacts due to climate change have been developed and applied. Especially, the variability of the meteorological factors such as rainfall, temperature, and evaporation can impact on the ecosystem in a basin. The variability caused by climate change on the meteorological factors can be divided by a gradual and abrupt change. Therefore, in this study, the gradual change is detected by simple linear regression and Mann-Kendall trend test. Also, the abrupt change is detected by Bayesian change point analysis. Finally, the result using these methods can identify the meteorological threats in the Cheongmicheon basin.

  • PDF

Air Change Rate Measurement Methods and Database

  • Lee, Kiyoung;Yukio Yanagisawa
    • Journal of Korean Society for Atmospheric Environment
    • /
    • 제11권E호
    • /
    • pp.1-12
    • /
    • 1995
  • In recent years the demand for energy conservation has resulted in "tight" buildings with decreased air change rates. Although a reduction in air change rates can save energy utilized for heating or cooling of dwellings, there is an increased concern for the air quality of the indoor environment where individuals spend most of their lifetime (Schwab et al., 1990).., 1990).

  • PDF

Thirty Years of Demographic Change in Korea: Implications for G Very Different Future

  • Day, Frederick A.
    • 대한지리학회:학술대회논문집
    • /
    • 대한지리학회 2003년도 추계학회술표회 논문집
    • /
    • pp.202-205
    • /
    • 2003
  • This paper is by nature a broad brush sweep of several ideas related to Korean demographic changes of the last 30 years. The paper summarizes recent birth and migration trends in Korea, emphasizing the rapidity of change, and that the very rapidly of change (for which Korea has become noted) has created some very special circumstances which, in turn, will have profound impacts on Korean society and economics in the not-so-distant future. (omitted)

  • PDF

Analysis of a Targeted Intervention Programme on the Risk Behaviours of Injecting Drug Users in India: Evidence From the National Integrated Biological and Behavioural Surveillance Survey

  • Sahu, Damodar;Ranjan, Varsha;Chandra, Nalini;Nair, Saritha;Kumar, Anil;Arumugam, Elangovan;Rao, Mendu Vishnu Vardhana
    • Journal of Preventive Medicine and Public Health
    • /
    • 제55권4호
    • /
    • pp.407-413
    • /
    • 2022
  • Objectives: This study provides insights on the impact of a targeted intervention (TI) programme on behaviour change among injecting drug users (IDUs) in India. Methods: This paper examined the data from the Integrated Biological and Behavioural Surveillance 2014-2015 for IDUs in India. Logistic regression was performed to understand the factors (TI programme services) that affected injecting risk behaviours by adjusting for covariates. Propensity score matching was conducted to understand the impact of the TI programme on using new needles/syringes and sharing needles/syringes in the most recent injecting episode by accounting for the covariates that predicted receiving the intervention. Results: Participants who received new needles and syringes from peer educators or outreach workers were 1.3 times (adjusted odds ratio, 1.29; 95% confidence interval [CI], 1.09 to 1.53) more likely to use new needles/syringes during most recent injecting episode than participants who did not receive needles/syringes. The matched-samples estimate (i.e., average treatment effect on treated) of using new needles in the most recent injecting episode showed a 2.8% (95% CI, 0.0 to 5.6) increase in the use of new needles and a 6.5% (95% CI, -9.7 to -3.3) decrease in needle sharing in the most recent injecting episode in participants who received new needles/syringes. There was a 2.2% (95% CI, -3.8 to -0.6) decrease in needle sharing in the most recent injecting episode among participants who were referred to other services (integrated counselling and testing centre, detox centres, etc.). Conclusions: The TI programme proved to be effective for behaviour change among IDUs, as substantiated by the use of new needles/syringes and sharing of needles/syringes.

최근 5년간 농업부문 온실가스 산정방법 개선과 그에 따른 배출량 차이 분석 (The Analysis of Differences by Improving GHG Emission Estimation Methodology for Agricultural Sector in Recent 5 Years)

  • 정현철;최은정;이종식;김건엽;이선일
    • 한국기후변화학회지
    • /
    • 제8권4호
    • /
    • pp.347-355
    • /
    • 2017
  • Methane and nitrous oxide are main greenhouse gases from agricultural system and their global warming potential are 25 and 258 times stronger than that of $CO_2$, respectively. In 2016, the emission was $21,290Gg\;tone\;CO_2-eq$. which was emitted from agriculture sector and about 3.1% of total GHG emission of Korea. Those guidelines that were published by IPCC have methodology for GHGs emission calculation as well as emission factor and so on. For recent 5 years, GHGs emissions in Korea have calculated by MRV which has been improved every year based on IPCC guidelines. Analysis as estimating method improvement showed that the methane emissions from rice cultivation were the lowest on 2012 methodology, and the highest on 2014 methodology. On the other hand, the emissions of agricultural soils were the lowest on 2015 methodology and the highest on 2012 methodology. Total emissions from agriculture sector were the lowest on 2015 methodology and the highest on 2012 methodology. Compared with 2016 methodology, the GHGs emitted as few as $-1,865Gg\;tone\;CO_2-eq$ and as many as $2,717Gg\;tone\;CO_2-eq$. GHGs emissions can vary greatly, depending on how to use the emission factor and activity data. Therefore, it need constantly a detailed analysis for methodology and GHGs emission in the future.