• Title/Summary/Keyword: Snow cover

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A study on the future snowmelt simulation using GIS - Soyanggang-dam and Chungju-dam Watersheds - (GIS 기반의 미래융설모의 연구 - 소양강댐, 충주댐 유역 -)

  • Shin, Hyung-Jin;Kang, Su-Man;Kwon, Hyung-Joong;Kim, Seong-Joon
    • 한국공간정보시스템학회:학술대회논문집
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    • 2005.11a
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    • pp.225-229
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    • 2005
  • The objective of this study is to evaluate snowmelt impact on watershed hydrology using climate change scenarios on Soyanggang-dam and Chungju-dam watershed. SLURP model was used for analyzing hydrological changes based on climate changes. The results (in years 2050 and 2100) of climate changes scenarios was CCCma CGCM2 of SRES suggested by IPCC and the snow cover map and snow depth was derived from NOAA/AVHRR images. The model was calibrated and verified for dam inflow data from 1998 to 2001.

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Snowmelt Impact on Watershed Hydrology Using Climate Change Scenarios - Soyanggang-dam and Chungju-dam Watersheds - (미래 기후변화에 따른 융설의 변화가 유역수문에 미치는 영향 - 소양강댐, 충주댐 유역 -)

  • Shin Hyung-Jin;Kang Su-Man;Kwon Hyung-Joong;Kim Seong-Joon
    • Proceedings of the KSRS Conference
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    • 2006.03a
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    • pp.198-201
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    • 2006
  • The objective of this study is to evaluate snowmelt impact on watershed hydrology using climate change scenarios on Soyanggang-dam and Chungju-dam watershed. SLURP model was used for analyzing hydrological changes based on climate changes. The results (in years 2050 and 2100) of climate changes scenarios was CCCma CGCM2 of SRES suggested by IPCC and the snow cover map and snow depth was derived from NOAA/AVHRR images. The model was calibrated and verified for dam inflow data from 1998 to 2001.

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Study for Snow Cover Characteristics Using Visible and SWIR channels from MODIS data (MODIS 적외 휘도 온도와 반사도를 이용한 적설역 특성 연구)

  • Yeom, Jong-Min;Han, Kyung-Soo;Park, Youn-Young;Lee, Chang-Suck;Kim, Young-Seup
    • Proceedings of the KSRS Conference
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    • 2007.03a
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    • pp.267-270
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    • 2007
  • 눈은 지표면의 물리과정에서 중요한 요소 중의 하나로 짧은 시간 동안에 많은 변화를 유도할 있다. 본 연구에 MODIS 채널자료를 이용하여 적설역에서 나타나는 단파적외 채널과 반사도 특성을 알아보았다 일반적으로 MODIS 위성자료를 이용한 적설연구는 근적외 채널을 활용한 NOSI (Normalized Difference of Snow Index)를 주로 사용한다. 하지만 본 연구는 정지기상 위성의 적셜 탐지 능력을 시험하기 위한 연구이다. 따라서 정지 기상 위성 탑재되어 있는 채널의 특성과 비슷한MODIS 가시 채널과 단파 적외 채널 자료를 이용하여 적설지역을 분석하였다단일 가시 채널을 이용하여 적설을 탐지 하는 것은 청천역일 경우 큰 어려움이 없으나 반면 구름과 적설이 혼재되어 있는 지역에서는 탐지 능력이 떨어진다.반면 BID 값을 활용한 적설지역 탐지는 단일 가시 채널을 활용한 방법보다 좋은 결과를 가지지만 하층운이 존재할 때는 여전히 적설과 구름을 명확히 구분하기는 어렵다.

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A Study on the Radar Reflectivity-Snowfall Rate Relation for Yeongdong Heavy Snowfall Events (영동 대설사례의 레이더 강설강도 추정 관계식에 관한 연구)

  • Jung, Sueng-Pil;Kwon, Tae-Yong;Park, Jun-Young;Choi, Byoung-Choel
    • Atmosphere
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    • v.26 no.4
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    • pp.509-522
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    • 2016
  • Heavy snowfall events have occurred frequently in the Yeongdong region but understanding of these events have trouble in lack of snowfall observation in this region because it is composed of complex topography like the "Taebaek mountains" and the "East sea". These problems can be solved by quantitative precipitation estimation technique using remote sensing such as radar, satellite, etc. Two radars which are able to cover over Yeondong region were installed at Gangneung (GNG) and Gwangdeoksan (GDK). This study uses radar and water equivalent of snow cover to investigate the characteristics of radar echoes and the $Z_e-R$ relations associated with the 10 Yeongdong heavy snowfall events during the last 5 years (2010~2014). It was found that the heights which the probability of detection (POD) of snow detection by GNG radar is more than 80% are 3,000 m and 1,500 m in convective cloud and stratiform cloud, respectively. The vertical gradient of radar reflectivity is less decreased in convective cloud than stratiform cloud. However, POD by GDK radar are lower than 80% at all layers because the majority of Yeondong observational stations are more than 100 km away from GDK radar site. Furthermore, we examined $Z_e-R$ relation from the 10 events using GNG radar and compared the "a" and "b" obtained from these examinations at Sokcho (SC) and Daegwallyeong (DG). These "a" and "b" are estimated from radar echo at 500 m (SC) and 1,500 m (DG). The values of "a" differ in their stations such as SC and DG are 30~116 and 6~39, respectively. But "b" is 0.4~1.7 irrespective of stations. Moreover, the value of "a" increased with surface air temperature. Therefore, quantitative precipitation estimation in heavy snowfall events by radar echo using fixed "a" and "b" is difficult because these values changed according to those precipitation characteristics.

Design of ICT based Protected Horticulture for Recovering Natural Disaster (ICT기반 시설원예 재해 경감장치 설계)

  • Lee, Meong-Hun;Yoe, Hyun
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.6 no.10
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    • pp.373-382
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    • 2016
  • Under the Agricultural technology is influenced from climate that is requisite of seasonal. So this system will cover the problems and develop the agricultural industry as well. So far, the agricultural industry is developing however, it has the points of the weakness because of natural disasters such as wind risk and heavy snow. This paper designs system to change vinyl on the greenhouse. This is a preliminary study for the real-time feedback control of greenhouse. The study developed a wireless IoT sensor system based on authentic technology capacities, to integrate with the protected horticulture Management System. These system was used to evaluate the levels of the snow cover and wind through IoT devices. The existing greenhouse uses the warm water to clear snow or to change methods. This system will recover by changing the vinyl which is covered outside of the greenhouse. The points of the system is changing vinyl to spin pipe. It is contained extra vinyl. The effects of this system are minimized labor protected crops from natural disasters. For this purpose, the study first developed a wireless IoT sensor unit that integrates an MEMS device and wireless communication module. Also, the study developed an operating program that enables real-time response measurement. It will help operational and maintenance greenhouse as a result.

INVESTIGATION OF CLOUD COVERAGE OVER ASIA WITH NOAA AVHRR TIME SERIES

  • Takeuchit Wataru;Yasuokat Yoshifumi
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.26-29
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    • 2005
  • In order to compute cloud coverage statistics over Asian region, an operational scheme for masking cloud-contaminated pixels in Advanced Very High Resolution Radiometer (AVHRR) daytime data was developed, evaluated and presented. Dynamic thresholding was used with channell, 2 and 3 to automatically create a cloud mask for a single image. Then the IO-day cloud coverage imagery was generated over the whole Asian region along with cloud-free composite imagery. Finally the monthly based statistics were computed based on the derived cloud coverage imagery in terms of land cover and country. As a result, it was found that 20-day is required to acquire the cloud free data over the whole Asia using NOAA AVHRR. The to-day cloud coverage and cloud-free composite imagery derived in this research is available via the web-site http://webpanda.iis.u-tokyo.ac.jp/CloudCover/.

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Risk Analysis of Thaw Penetration Due to Global Climate Change in Cold Regions

  • Bae, Yoon-Shin
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.2
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    • pp.45-51
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    • 2009
  • A probabilistic approach may be adopted to predict freeze and thaw depths to account for the variability of (1) material properties, and (2) contemporary and future surface energy input parameters(e.g. air temperatures, cloud cover, snow cover) predicted with global climate models. To illustrate the probabilistic approach, an example of the predicted of thaw depths in cold regions is considered. More specifically, the Stefan equation is used together with the Monte Carlo simulation technique to make a probabilistic prediction of thaw penetration. The simulation results indicate that the variability in material properties, surface energy input parameters and temperature data can lead to significant uncertainty in predicting thaw penetration.

A Study on High-Resolution Seasonal Variations of Major Ionic Species in Recent Snow Near the Antarctic Jang Bogo Station (남극 장보고과학기지 인근에서 채취한 눈시료 내의 주요 이온성분들의 고해상도 계절변동성 연구)

  • Kwak, Hoje;Kang, Jung-Ho;Hong, Sang-Bum;Lee, Jeonghoon;Chang, Chaewon;Hur, Soon Do;Hong, Sungmin
    • Ocean and Polar Research
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    • v.37 no.2
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    • pp.127-140
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    • 2015
  • A continuous series of 60 snow samples was collected at a 2.5-cm interval from a 1.5-m snow pit at a site on the Styx Glacier Plateau in Victoria Land, Antarctica, during the 2011/2012 austral summer season. Various chemical components (${\delta}D$, ${\delta}^{18}O$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $SO_4{^2-}$, $NO_3{^-}$, $F^-$, $CH_3SO_3{^-}$, $CH_3CO_2{^-}$ and $HCO_2{^-}$) were determined to understand the highly resolved seasonal variations of these species in the coastal atmosphere near the Antarctic Jang Bogo station. Based on vertical profiles of ${\delta}^{18}O$, $NO_3{^-}$and MSA, which showed prominent seasonal changes in concentrations, the snow samples were dated to cover the time period from 2009 austral winter to 2012 austral summer with a mean accumulation rate of $226kgH_2Om^{-2}yr^{-1}$. Our snow profiles show pronounced seasonal variations for all the measured chemical species with a different pattern between different species. The distinctive feature of the occurrence patterns of the seasonal variations is clearly linked to changes in the relative strength of contributions from various natural sources (sea salt spray, volcanoes, crust-derived dust, and marine biogenic activities) during different short-term periods. The results allow us to understand the transport pathways and input mechanisms for each species and provide valuable information that will be useful for investigating long-term (decades to century scale periods) climate and environmental changes that can be deduced from an ice core to be retrieved from the Styx Glacier Plateau in the near future.

Development of block-type sidewalk pavement system using snow-melting system (융설시스템을 이용한 조립식 보도포장 기술 개발)

  • Park, Kyungmo;Lee, Jeonguk;Kim, Changduk
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.6
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    • pp.136-143
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    • 2015
  • Snow-melting system has been applied not only to roads for car traffic but also to pavement for the pedestrians safety reason in some of the developed countries such as USA and Canada based on countermeasures against Natural Disasters Act revised in 2000. Even though this system was introduced in korea in 2006 and has been partly applied to car traffic roads, there is few places that the system has been applied. Therefore, in this research a snow-melting system with a block-type to cover a pavement that efficiently transfers heat form heat rays to the top of a pavement and protects the heat rays. A quality check showed that compression and bending strength was improved approximately 5 times stronger and 7 to 10 times more absorption rate than the KS(Korea Industrial Standard) requirement. Moreover, only 10 minute was required to increase temperature above zero with a block-type snow-melting system whereas approximately 180 minute was spent with the existing system. This research is expected to contribute to environmental issues and reduce accidents on a slippery road.

Influence of microenvironment on the spatial distribution of Himantormia lugubris (Parmeliaceae) in ASPA No. 171, maritime Antarctic

  • Choi, Seung Ho;Kim, Seok Cheol;Hong, Soon Gyu;Lee, Kyu Song
    • Journal of Ecology and Environment
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    • v.38 no.4
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    • pp.493-503
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    • 2015
  • This study analyzed how spatial distribution of Himantormia lugubris is affected by the microenvironment in the Antarctic Specially Protected Area (ASPA) No. 171 located in the Barton Peninsula of King George Island that belongs to the maritime Antarctic. In order to determine the population structure of H. lugubris growing in Baekje Hill within ASPA No. 171, we counted the individuals of different size groups after dividing the population into 5 growth stages according to mean diameter as follows: ≤ 1 cm, 1-3 cm, 3-5 cm, 5-10 cm, and ≥ 10 cm. The count of H. lugubris individuals in each growth stage was converted into its percentage with respect to the entire population, which yielded the finding that stages 1 through 5 accounted for 32.8%, 25.3%, 15.9%, 22.5%, and 3.5%, respectively. This suggests that the population of H. lugubris in ASPA No. 171 has a stable reverse J-shaped population structure, with the younger individuals outnumbering mature ones. The mean density of H. lugubris was 17.6/0.25 m2, mean canopy cover 13.3%, and the mean dry weight 37.8 g/0.25 m2. It began to produce spore in the sizes over 3 cm, and most individuals measuring 5-10 cm were adults with sexually mature apothecia. The spatial distribution of H. lugubris was highly heterogeneous. The major factors influencing its distribution and performance were found to be the period covered by snow, wind direction, moisture, size of the substrate, and canopy cover of Usnea spp. Based on these factors, we constructed a prediction model for estimating the spatial distribution of H. lugubris. Conclusively, the major factors for the spatial distribution of H. lugubris were snow, wind, substrate and the competition with Usnea spp. These results are important for understanding of the distribution in the maritime Antarctic and evolution of H. lugubris that claims a unique life history and ecological niche.