• Title/Summary/Keyword: Snow cover areas

Search Result 20, Processing Time 0.024 seconds

Improvement of infrared channel emissivity data in COMS observation area from recent MODIS data(2009-2012) (최근 MODIS 자료(2009-2012)를 이용한 천리안 관측 지역의 적외채널 방출률 자료 개선)

  • Park, Ki-Hong;Suh, Myoung-Seok
    • Korean Journal of Remote Sensing
    • /
    • v.30 no.1
    • /
    • pp.109-126
    • /
    • 2014
  • We improved the Land Surface Emissivity (LSE) data (Kongju National University LSE v.2: KNULSE_v2) over the Communication, Ocean and Meteorological Satellite (COMS) observation region using recent(2009-2012) Moderate Resolution Imaging Spectroradiometer (MODIS) data. The surface emissivity was derived using the Vegetation Cover Method (VCM) based on the assumption that the pixel is only composed of ground and vegetation. The main issues addressed in this study are as follows: 1) the impacts of snow cover are included using Normalized Difference Snow Index (NDSI) data, 2) the number of channels is extended from two (11, 12 ${\mu}m$) to four channels (3.7, 8.7, 11, 12 ${\mu}m$), 3) the land cover map data is also updated using the optimized remapping of the five state-of-the-art land cover maps, and 4) the latest look-up table for the emissivity of land surface according to the land cover is used. The updated emissivity data showed a strong seasonal variation with high and low values for the summer and winter, respectively. However, the surface emissivity over the desert or evergreen tree areas showed a relatively weak seasonal variation irrespective of the channels. The snow cover generally increases the emissivity of 3.7, 8.7, and 11 ${\mu}m$ but decreases that of 12 ${\mu}m$. As the results show, the pattern correlation between the updated emissivity data and the MODIS LSE data is clearly increased for the winter season, in particular, the 11 ${\mu}m$. However, the differences between the two emissivity data are slightly increased with a maximum increase in the 3.7 ${\mu}m$. The emissivity data updated in this study can be used for the improvement of accuracy of land surface temperature derived from the infrared channel data of COMS.

Enhancing GEMS Surface Reflectance in Snow-Covered Regions through Combined of GeoKompsat-2A/2B Data (천리안 위성자료 융합을 통한 적설역에서의 GEMS 지표면 반사도 개선 연구)

  • Suyoung Sim;Daeseong Jung;Jongho Woo;Nayeon Kim;Sungwoo Park;Hyunkee Hong;Kyung-Soo Han
    • Korean Journal of Remote Sensing
    • /
    • v.39 no.6_1
    • /
    • pp.1497-1503
    • /
    • 2023
  • To address challenges in classifying clouds and snow cover when calculating ground reflectance in Near-UltraViolet (UV) wavelengths, this study introduces a methodology that combines cloud data from the Geostationary Environmental Monitoring Spectrometer (GEMS) and the Advanced Meteorological Imager (AMI)satellites for snow cover analysis. The proposed approach aims to enhance the quality of surface reflectance calculations, and combined cloud data were generated by integrating GEMS cloud data with AMI cloud detection data. When applied to compute GEMS surface reflectance, this fusion approach significantly mitigated underestimation issues compared to using only GEMS cloud data in snow-covered regions, resulting in an approximately 17% improvement across the entire observational area. The findings of this study highlight the potential to address persistent underestimation challenges in snow areas by employing fused cloud data, consequently enhancing the accuracy of other Level-2 products based on improved surface reflectivity.

Selecting Suitable Riparian Wildlife Passage Locations for Water Deer based on MaxEnt Model and Wildlife Crossing Analysis (MaxEnt 모형과 고라니의 이동행태를 고려한 수변지역 이동통로 적지선정)

  • Jeong, Seung Gyu;Lee, Hwa Su;Park, Jong Hoon;Lee, Dong Kun;Park, Chong Hwa;Seo, Chang Wan
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.23 no.1
    • /
    • pp.101-111
    • /
    • 2015
  • Stream restoration projects have become threats to riparian ecosystem in Rep. of korea. Riparian wildlife becomes isolated and the animals are often experience difficulties in crossing riparian corridors. The purposes of this study is to select suitable wildlife passages for wild animals crossing riparian corridors. Maximum entropy model and snow tracking data on embankment in winter seasons were used to develop species distribution models to select suitable wildlife passages for water deer. The analysis suggests the following. Firstly, most significant factors for water deer's habitat in area nearby riparian area are shown to distance to water, age-class, land cover, slope, aspect, digital elevation model, tree density, and distance to road. For the riparian area, significant factors are shown to be land cover, size of riparian area, distance to tributary, and distance to built-up. Secondly, the suitable wildlife passages are recommended to reflect areas of high suitability with Maximum Entropy model in riparian areas and the surrounding areas and moving passages. The selected suitable areas are shown to be areas with low connectivity due to roads and vertical levee although typical habitats for water deer are forest, grassland, and farmland. In addition, the analysis of traces on snow suggests that the water deer make a detour around the artificial structures. In addition, the water deer are shown to make a detour around the fences of roads and embankment around farmland. Lastly, the water deer prefer habitats around riparian areas following tributaries. The method used in this study is expected to provide cost-efficient and functional analysis in selecting suitable areas.

Evaluating Vulnerability to Snowfall Disasters Using Entropy Method for Overlapping Distributions of Vulnerable Factors in Busan, Korea (취약인자의 엔트로피 기반 중첩 분석을 이용한 부산광역시의 적설재해 취약지역 등급 평가)

  • An, ChanJung;Park, Yongmi;Choi, Wonsik
    • Korean Journal of Remote Sensing
    • /
    • v.36 no.2_1
    • /
    • pp.217-229
    • /
    • 2020
  • Recently, weather changes in Korea have intensified due to global warming, and the five major natural disasters that occur mostly include heavy rains, typhoons, storms, heavy snow, and earthquakes. Busan is vulnerable to snow disaster, given that the amount of natural disaster damage in Busan accounts for more than 50% of the total amount in the entire metropolitan cities in Korea, and that the Busan area includes many hilly mountains. In this study, we attempted to identify vulnerable areas for snowfall disasters in Busan areas using the geographic information system (GIS) with the data for both geographical and anthropogenic characteristics. We produced the maps of vulnerable areas for evaluating factors that include altitude, slope, land cover, road networks, and demographics, and overlapped those maps to rank the vulnerability to snowfall disasters as the 5th levels finally. To weight each evaluating factor, we used an entropy method. The riskiest areas are characterized by being located in mountainous areas with roads, including Sansung-ro in Geumjeong-gu, Mandeok tunnel in Buk-gu, Hwangnyeongsan-ro in Suyeong-gu, and others, where road restrictions were actually enforced due to snowfall events in the past. This method is simple and easy to be updated, and thus we think this methodology can be adapted to identify vulnerable areas for other environmental disasters.

Estimation of Greenhouse Damaged Area by Heavy Snowfall using GIS and Remote Sensing Technique (논문 - GIS/RS를 이용한 비닐하우스 폭설 피해지역 추출 기법 연구)

  • Kim, Saet-Byul;Shin, Hyung-Jin;Yun, Dong-Koun;Hong, Sung-Wook;Kim, Seong-Joon
    • KCID journal
    • /
    • v.18 no.2
    • /
    • pp.111-121
    • /
    • 2011
  • This study is to estimate the possible damage area of greenhouse by heavy snowfall event using terra MODIS snow cover area (SCA) and the ground measured snowfall data (GMSD). For the 4 heavy snowfall events of January 2001, March 2004, December 2005 and January 2010, the areas exceeding the design criteria of snowfall depth for greenhouse breaking were extracted by coupling the MODIS SCA and GMSD. The main damaged regions were estimated as Gangwon province in 2001, Chungbuk and part of Gyeongbuk province in 2004, Jeonbuk and Jeonnam province in 2005, and Gangwon and part of Gyeonggi province in 2010 respectively. Comparing with the investigated number of greenhouse damaged data, the estimated areas reflected the statistical data except 2001. The 2001 greenhouse damages were caused by the high wind speed (35.7m/sec) together with snowfall. The results of this study can be improved if the design criteria of wind speed is added.

  • PDF

Characteristics of Habitat-using of Siberian Roe Deer in Seoraksan(Mt.) National Park (설악산국립공원 지역의 노루 서식지 이용 특성에 관한 연구)

  • Park, Yong-Su;Lee, Woo-Shin
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.17 no.1
    • /
    • pp.91-109
    • /
    • 2014
  • This study was conducted to obtain the basic research about Siberian roe deer (Capreolus pygargus), and to establish a conservation area into Seoraksan(Mt.) National Park, South Korea. We recorded Siberian roe deer field signs (bedding sites, feeding areas, feces and tracks etc), and habitat variables such as nearest distance to the watercourse, trails, slope, aspect, forest type and land cover etc. from Jan. 2006 to Dec. 2007 in Seoraksan(Mt.) National Park. According to the research of habitat characteristics of Siberian roe deer inhabited in Seoraksan(Mt.) National Park preferred mixed forest consisted of aged forest and middle-aged forest on the gentle slope which was close to hydrosphere in the middle elevation area of altitude of 400~600m above sea level in Seoraksan(Mt.) National Park. The results indicated that Siberian roe deer appeared to prefer south slope or north slope during the snow season and west or east slope during the non-snow season. The area of most suitable habitat for Siberian roe deer in Seoraksan(Mt.) National Park was $128.5km^2$ (32% of the total area) followed by $244.3km^2$ buffer area (62.2% of the total area), and $22.9km^2$ unsuitable habitat area (5.8% of the total area), which means environmentally unsuitable habitat for Siberian roe deer was rare in Seoraksan(Mt.) National Park. Thus, the area classified as major area in Seoraksan(Mt.) National Park appeared to be most important for the protection of Siberian roe deer.

Characteristics and Synoptic Causes on the Abnormal Heat Occurred at Miryang in 2004 (2004년 밀양의 이상더위의 특징과 종관적 원인)

  • Byun, Hi Ryong;Hwang, Ho Seong;Go, Hye Young
    • Atmosphere
    • /
    • v.16 no.3
    • /
    • pp.187-201
    • /
    • 2006
  • During summer (JJA) of 2004, a record-high temperature in Korea appeared at Miryang ($38.5^{\circ}C$ on July 30). Moreover, Miryang showed the most frequent occurrence (25 days in JJA) of the daily highest temperature among observational sites in Korea. Based on meteorological analysis, it is found that this phenomenon is caused by neither the global warming effect nor the urban climate effect. It is caused by the mesoscale and synoptic and/or global scale atmospheric circulations, as evidenced by several factors described below. Firstly, the hottest areas have normally occurred not at a point but over an area, particularly along an axis connecting Sancheong and Daegu. But in 2004, this axis has moved southward and locates over Namhae-Miryang due to northerlies that were induced by the heating effect related to the low snow-cover on the Tibet Plateau. Secondly, although the maximum temperature was the highest among observational sites in Korea, the daily mean temperature and the number of nights with air temperature over $25^{\circ}C$ were not the highest at Miryang. Thirdly, the downdraft induced by the second circulation of typhoon and abnormal development of the North-Pacific High were found to have exerted an important role.

Production of clothes for beach volleyball players: Safe against ultraviolet radiation damage

  • He Huang
    • Geomechanics and Engineering
    • /
    • v.32 no.6
    • /
    • pp.627-637
    • /
    • 2023
  • Volleyball is an international sport with many fans. This sport has made significant progress in schools and clubs. Volleyball is suitable for all age groups and can be used in different environments. It has many social and physical benefits. During the game provides special physical training for the players and is considered one of the most exciting games. Another type of volleyball is beach volleyball, a beach sport and one of the Olympic sports held on the sand with the same rules as volleyball. This sport is usually played in coastal areas, especially with wide sandy beaches. Because this sport is played in open spaces, the players stay in this space for a long time and are exposed to dangerous ultraviolet radiation. It is a wavelength of light in the range of electromagnetic waves with a wavelength between 10 and 400 nm. This wavelength is shorter than visible light and more protracted than X-ray. Ultraviolet (UV) rays are naturally present in sunlight and include about 10% of all waves emitted from the sun's surface. Prolonged exposure to ultraviolet light causes acute and chronic damage to the skin and vision and even destroys the entire immune system. Different covers of the earth's surface reflect different amounts of UV rays. For example, snow cover, sand, and seawater surface reflect this radiation. Therefore, the health of volleyball players is in danger due to this harmful radiation. This work aims to introduce a type of clothing made of nanoparticles that can repel ultraviolet rays and protect beach volleyball players whose health is at risk from this radiation.

Analysis of Spatio-Temporal Patterns of Nighttime Light Brightness of Seoul Metropolitan Area using VIIRS-DNB Data (VIIRS-DNB 데이터를 이용한 수도권 야간 빛 강도의 시·공간 패턴 분석)

  • Zhu, Lei;Cho, Daeheon;Lee, Soyoung
    • Journal of Cadastre & Land InformatiX
    • /
    • v.47 no.2
    • /
    • pp.19-37
    • /
    • 2017
  • Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS-DNB) data provides a much higher capability for observing and quantifying nighttime light (NTL) brightness in comparison with Defense Meteorological Satellite-Operational Linescan System (DMSP-OLS) data. In South Korea, there is little research on the detection of NTL brightness change using VIIRS-DNB data. This study analyzed the spatial distribution and change of NTL brightness between 2013 and 2016 using VIIRS-DNB data, and detected its spatial relation with possible influencing factors using regression models. The intra-year seasonality of NTL brightness in 2016 was also studied by analyzing the deviation and change clusters, as well as the influencing factors. Results are as follows: 1) The higher value of NTL brightness in 2013 and 2016 is concentrated in Seoul and its surrounding cities, which positively correlated with population density and residential areas, economic land use, and other factors; 2) There is a decreasing trend of NTL brightness from 2013 to 2016, which is obvious in Seoul, with the change of population density and area of industrial buildings as the main influencing factors; 3) Areas in Seoul, and some surrounding areas have high deviation of the intra-year NTL brightness, and 71% of the total areas have their highest NTL brightness in January, February, October, November and December; and 4) Change of NTL brightness between summer and winter demonstrated a significantly positive relation with snow cover area change, and a slightly and significantly negative relation with albedo change.

Analyzing Spatial and Temporal Variation of Ground Surface Temperature in Korea (국내 지면온도의 시공간적 변화 분석)

  • Koo Min-Ho;Song Yoon-Ho;Lee Jun-Hak
    • Economic and Environmental Geology
    • /
    • v.39 no.3 s.178
    • /
    • pp.255-268
    • /
    • 2006
  • Recent 22-year (1981-2002) meteorological data of 58 Korea Meteorological Adminstration (KMA) station were analyzed to investigate spatial and temporal variation of surface air temperature (SAT) and ground surface temperature (GST) in Korea. Based on the KMA data, multiple linear regression (MLR) models, having two regression variables of latitude and altitude, were presented to predict mean surface air temperature (MSAT) and mean ground surface temperature (MGST). Both models showed a high accuracy of prediction with $R^2$ values of 0.92 and 0.94, respectively. The prediction of MGST is particularly important in the areas of geothermal energy utilization, since it is a critical parameter of input for designing the ground source heat pump system. Thus, due to a good performance of the MGST regression model, it is expected that the model can be a useful tool for preliminary evaluation of MGST in the area of interest with no reliable data. By a simple linear regression, temporal variation of SAT was analyzed to examine long-term increase of SAT due to the global warming and the urbanization effect. All of the KMA stations except one showed an increasing trend of SAT with a range between 0.005 and $0.088^{\circ}C/yr$ and a mean of $0.043^{\circ}C/yr$. In terms of meteorological factors controlling variation of GST, the effects of solar radiation, terrestrial radiation, precipitation, and snow cover were also discussed based on quantitative and qualitative analysis of the meteorological data.