• Title/Summary/Keyword: global climate

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Thermal and light impacts on the early growth stages of the kelp Saccharina angustissima (Laminariales, Phaeophyceae)

  • Augyte, Simona;Yarish, Charles;Neefus, Christopher D.
    • ALGAE
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    • v.34 no.2
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    • pp.153-162
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    • 2019
  • Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between $7-18^{\circ}C$ with irradiance at 20, 40, and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$. The second set combined temperatures of $3-13^{\circ}C$ with irradiance of 10, 100, and $200{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of $8-13^{\circ}C$ at the lowest irradiance of $10-{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of $8-15^{\circ}C$ and irradiance levels of $10-100{\mu}mol\;photons\;m^{-2}\;s^{-1}$ were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes-the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.

Categorical Prediction and Improvement Plan of Snow Damage Estimation using Random Forest (랜덤포레스트를 이용한 대설피해액에 대한 범주형 예측 및 개선방안 검토)

  • Lee, Hyeong Joo;Chung, Gunhui
    • Journal of Wetlands Research
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    • v.21 no.2
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    • pp.157-162
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    • 2019
  • Recently, the occurrence of unusual heavy snow and cold are increasing due to the unusual global climate change. In particular, the temperature dropped to minus 69 degrees Celsius in the United States on January 8, 2018. In Korea, on February 17, 2014, the auditorium building in Gyeongju Mauna Resort was collapsed due to the heavy snowfall. Because of the tragic accident many studies on the reduction of snow damage is being conducted, but it is difficult to predict the exact damage due to the lack of historical damage data, and uncertainty of meteorological data due to the long distance between the damaged area and the observatory. Therefore, in this study, available data were collected from factors that are thought to be corresponding to snow damage, and the amount of snow damage was estimated categorically using a random forest. At present, the prediction accuracy was not sufficient due to lack of historical damage data and changes of the design code for green houses. However, if accurate weather data are obtained in the affected areas. the accuracy of estimates would increase enough for being used for be the degree preparedness of disaster management.

Satellite-based Evaporative Stress Index (ESI) as an Indicator of Agricultural Drought in North Korea (Evaporative Stress Index (ESI)를 활용한 북한의 위성영상기반 농업가뭄 평가)

  • Lee, Hee-Jin;Nam, Won-Ho;Yoon, Dong-Hyun;Hong, Eun-Mi;Kim, Dae-Eui;Svoboda, Mark D.;Tadesse, Tsegaye;Wardlow, Brian D.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.61 no.3
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    • pp.1-14
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    • 2019
  • North Korea has frequently suffered from extreme agricultural crop droughts, which have led to food shortages, according to the Food and Agriculture Organization (FAO). The increasing frequency of extreme droughts, due to global warming and climate change, has increased the importance of enhancing the national capacity for drought management. Historically, a meteorological drought index based on data collected from weather stations has been widely used. But it has limitations in terms of the distribution of weather stations and the spatial pattern of drought impacts. Satellite-based data can be obtained with the same accuracy and at regular intervals, and is useful for long-term change analysis and environmental monitoring and wide area access in time and space. The Evaporative Stress Index (ESI), a satellite-based drought index using the ratio of potential and actual evaporation, is being used to detect drought response as a index of the droughts occurring rapidly over short periods of time. It is more accurate and provides faster analysis of drought conditions compared to the Standardized Precipitation Index (SPI), and the Palmer Drought Severity Index (PDSI). In this study, we analyze drought events during 2015-2017 in North Korea using the ESI satellite-based drought index to determine drought response by comparing with it with the SPI and SPEI drought indices.

Development of a Low Cost Smart Farm System for Cultivating High Value-added Specialized Crops (고부가가치 특용작물 재배를 위한 보급형 스마트팜 시스템 개발)

  • Ju, Yeong-Tae;Kim, Sung-Cho;Kim, Eung-Kon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.4
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    • pp.743-748
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    • 2021
  • Amid the global population growth and climate change, high-tech smart farm technology that combines agriculture and ICT is actively being researched in Korea to solve sustainable crises such as declining population of agricultural and livestock industries. Existing smart farms are growing mainly on crops with low price competitiveness. Food consumption structures are becoming more sophisticated and diverse, and as agricultural consumption patterns change, the smart farm system also needs to be optimized for growing high-value special crops. To this end, an integrated ICT management system was designed and implemented by establishing a containerized smart farm environment specialized in growing sprout ginseng. Through this, it is possible to implement high-tech agricultural production and lead new future convergence industries through the convergence of ICT, agriculture, and the latest technologies and farming.

Evaluation of GSICS Correction for COMS/MI Visible Channel Using S-NPP/VIIRS

  • Jin, Donghyun;Lee, Soobong;Lee, Seonyoung;Jung, Daeseong;Sim, Suyoung;Huh, Morang;Han, Kyung-soo
    • Korean Journal of Remote Sensing
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    • v.37 no.1
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    • pp.169-176
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    • 2021
  • The Global Space-based Inter-Calibration System (GSICS) is an international partnership sponsored by World Meteorological Organization (WMO) to continue and improve climate monitoring and to ensure consistent accuracy between observation data from meteorological satellites operating around the world. The objective for GSICS is to inter-calibration from pairs of satellites observations, which includes direct comparison of collocated Geostationary Earth Orbit (GEO)-Low Earth Orbit (LEO) observations. One of the GSICS inter-calibration methods, the Ray-matching technique, is a surrogate approach that uses matched, co-angled and co-located pixels to transfer the calibration from a well calibrated satellite sensor to another sensor. In Korea, the first GEO satellite, Communication Ocean and Meteorological Satellite (COMS), is used to participate in the GSICS program. The National Meteorological Satellite Center (NMSC), which operated COMS/MI, calculated the Radiative Transfer Model (RTM)-based GSICS coefficient coefficients. The L1P reproduced through GSICS correction coefficient showed lower RMSE and Bias than L1B without GSICS correction coefficient applied. The calculation cycles of the GSICS correction coefficients for COMS/MI visible channel are provided annual and diurnal (2, 5, 10, 14-day), but long-term evaluation according to these cycles was not performed. The purpose of this paper is to perform evaluation depending on the annual/diurnal cycles of COMS/MI GSICS correction coefficients based on the ray-matching technique using Suomi-NPP/Visible Infrared Imaging Radiometer Suite (VIIRS) data as reference data. As a result of evaluation, the diurnal cycle had a higher coincidence rate with the reference data than the annual cycle, and the 14-day diurnal cycle was the most suitable for use as the GSICS correction coefficient.

A Study on the Quantitative Risk Assessment of Mobile Hydrogen Refueling Station (이동식수소스테이션 정량적 위험성평가에 관한 연구)

  • KIM, DONG-HWAN;LEE, SU-MIN;JOE, CHOONG-HEE;KANG, SEUNG KYU;HUH, YUN-SIL
    • Journal of Hydrogen and New Energy
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    • v.31 no.6
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    • pp.605-613
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    • 2020
  • In July and October of this year, the government announced the 'Green new deal plan within the Korean new deal policy' and 'Strategies for proliferation of future vehicles and market preoccupation'. And, in response to changes in the global climate agreement, it has decided to expand green mobility such as electric vehicles and hydrogen electric vehicles with the aim of a "net-zero" society. Accordingly, the goal is to build 310 hydrogen refueling stations along with the supply of 60,000 hydrogen vehicles in 2022, and the hydrogen infrastructure is being expanded. however, it is difficult to secure hydrogen infrastructure due to expensive construction costs and difficulty the selection of a site. In Korea, it is possible to build a mobile hydrogen station according to the safety standards covering special case of the Ministry of Industry. Since the mobile hydrogen station can be charged while moving between authorized place, it has the advantage of being able to meet a large number of demands with only one hydrogen refueling station, so it is proposed as a model suitable for the early market of hydrogen infrastructure. This study demonstrates the establishment of a hydrogen refueling station by deriving a virtual accident scenario for leakage and catastrupture for each facility for the risk factors in a mobile hydrogen station, and performing a quantitative risk assessment through the derived scenario. Through the virtual accident scenario, direction of demonstration and implications for the construction of a mobile hydrogen refueling station were derived.

A Study on the Prototype Setting for Energy Independent Site Planning (에너지 자립형 단지계획 프로토타입 설정에 관한 연구)

  • Ha, Seung-Beom
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.2
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    • pp.359-366
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    • 2021
  • It's been more than 30 years since global warming by the increase in CO2 became a cause celebre worldwide. Recently the government promulgated Framework Act on on Low-Carbon Green Growth and has been continuously putting much effort into saving energy and reducing carbon dioxide emissions such as an international climate change conference to prevent the increase in CO2. However, because most cities are not planned for energy saving, new cities should be planned as the active energy-efficient urban structure for 'sustainable urban development' from a long-term perspective. This study aims to design a new prototype for the sustainable energy-independent and environment-friendly housing estates which is the nation's new vision in the era of the Fourth Industrial Revolution. A study on the energy-independent site planning and the quantitative standardization of its factor will be conducted.

Christian Challenges to Overcome the Environmental Crisis (환경 위기 극복을 위한 기독교적 과제)

  • Bong, Won Young
    • The Journal of the Korea Contents Association
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    • v.21 no.6
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    • pp.456-465
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    • 2021
  • A recent report cited environmental issues, including climate change, as the most likely threat to Earth in the 2020s. Therefore, it is necessary to recognize that environmental problems today are not just problems of any particular region or country, but also problems of the future, and problems of the present day in which we live. Various interests and research on environmental issues have been conducted within Christianity based on the Christian worldview based on creation, degradation, and restraint. This interest began mainly in the Catholic camp in the early days, but gradually efforts have been made to link global care to Christian responsibility in evangelical Christian camps, including the World Council of Churches (WCC). At a time when interest in earth care is growing, the study suggested as follows for the Christian community: First, it is necessary to change from environmental protection and ecological preservation to life theology. Second, there is a need for a change of understanding of ecology that looks at nature. Third, at the Christian level, there should be a genuine recovery movement that is differentiated from secular environmentalism. Fourth, the church should be able to realize a society that can realize a true community with the world of creation while looking forward to the kingdom of God.

Characterizing Spatiotemporal Variations and Mass Balance of CO2 in a Stratified Reservoir using CE-QUAL-W2 (CE-QUAL-W2를 이용한 성층 저수지에서 CO2의 시공간적 분포 및 물질수지 분석)

  • Park, Hyungseok;Chung, Sewoong
    • Journal of Korean Society on Water Environment
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    • v.36 no.6
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    • pp.508-520
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    • 2020
  • Dam reservoirs have been reported to contribute significantly to global carbon emissions, but unlike natural lakes, there is considerable uncertainty in calculating carbon emissions due to the complex of emission pathways. In particular, the method of calculating carbon dioxide (CO2) net atmospheric flux (NAF) based on a simple gas exchange theory from sporadic data has limitations in explaining the spatiotemporal variations in the CO2 flux in stratified reservoirs. This study was aimed to analyze the spatial and temporal CO2 distribution and mass balance in Daecheong Reservoir, located in the mid-latitude monsoon climate zone, by applying a two-dimensional hydrodynamic and water quality model (CE-QUAL-W2). Simulation results showed that the Daecheong Reservoir is a heterotrophic system in which CO2 is supersaturated as a whole and releases CO2 to the atmosphere. Spatially, CO2 emissions were greater in the lacustrine zone than in the riverine and transition zones. In terms of time, CO2 emissions changed dynamically according to the temporal stratification structure of the reservoir and temporal variations of algae biomass. CO2 emissions were greater at night than during the day and were seasonally greatest in winter. The CO2 NAF calculated by the CE-QUAL-W2 model and the gas exchange theory showed a similar range, but there was a difference in the point of occurrence of the peak value. The findings provide useful information to improve the quantification of CO2 emissions from reservoirs. In order to reduce the uncertainty in the estimation of reservoir carbon emissions, more precise monitoring in time and space is required.

How to Respond to Complex Disasters on Future Megacities at the Government Level (미래 메가시티의 복합재난과 범정부 차원의 대응 방향)

  • Moon, Sang Jun;Cho, Sang Keun;Jung, Min-Sub;Park, Sang-Hyuk
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.1
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    • pp.211-215
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    • 2021
  • The number of megacities are increasing, due to the global urbanization. Along with this change, climate change, social development and technology advance make the calamities complicated and more devastating. Especially, megacities are hyper-netted, hyper-connected and hyper-converged with population more than 10 million and their domain. When calamities break out, the damage will be aggravated for they lead to another ones. Since megacities are the center of politics, economics and culture of a nation. so when complex disaster break out in megacities, this may be developed to a peril to the national security. Therefore, pan-government effort must be concentrated in preparing abilities to forecast, react, rapid response and resilience.