• 제목/요약/키워드: temperature inversion

검색결과 299건 처리시간 0.031초

CHARACTERISTICS OF LOW LEVEL TEMPERATURE INVERSION IN TAIWAN

  • Liou Yuei-An;Yan Shiang-Kun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.38-41
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    • 2005
  • The observation data from MTP-5HE ofEPA are used to study the temperature inversion phenomenon in the lower boundary layer in Taipei, Taichung and Kaohsiung of Taiwan. Characteristics of temperature inversion at three cities are extracted using different classification methods. The characteristics of temperature inversion in Taichung and Kaohsiung show a similar trend but are different from that in Taipei. The numbers of the occurrence of temperature inversion in Taichung and Kaohsiung were much larger than that in Taipei. The main types of temperature inversion in Taiwan are radiation inversion and frontal inversion. Compared to frontal inversion, radiation inversion on average occurs at a lower altitude, lasts a longer period, has a deeper thickness, and reaches a higher temperature difference of inversion. Frontal inversion plays a significant role for the inversion event lasting over 12 hours.

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A STUDY OF LOW-LEVEL BOUNDARY-LAYER TEMPERATURE INVERSION EVENTS IN TAIWAN

  • Liou, Yuei-An;Yan, Shiang-Kun;Wang, Kuo-Chung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.320-323
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    • 2006
  • Temperature inversion may cause air pollution problems because air pollutants cannot be dissipated through vertical motion of the atmosphere and are accumulated near the surface. The air quality is worsen gradually if an inversion event lasts for a long time. An inversion event is defined as consecutive temperature profiles with occurrence of the temperature inversion condition. In this paper, temperature inversion events over three major cities on Taiwan are analyzed. They are measured by ground-based microwave radiometers installed in Taipei, Taichung, and Kaohsiung from 2002 to 2004 by the Environment Protection Administration (EPA) of Taiwan. Characteristics of temperature inversion events at the three cities are extracted using different classification methods.

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2015년 4월에 제주 서부해역에서 발생한 수온역전층 특성 (Characteristics of Water Temperature Inversion Observed in a Region West of Jeju Island in April 2015)

  • 김성현
    • Ocean and Polar Research
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    • 제42권2호
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    • pp.97-113
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    • 2020
  • In-situ observations were carried out in April 2015 to investigate the occurrence of water temperature inversion in a region west of Jeju Island. Analysis of in-situ in the western part of Jeju island showed that cold water moved to the southeast from the surface to the middle layer and warm water moved from the middle to the lower layer of the northwest direction. The water temperature inversion occurred at 84 stations (63.1%) out of 133 stations. At the boundary of the water temperature inversion layer, it was formed in the middle layer and disappeared. In the strongly appearing, it started from the middle layer to the lower layer. The shape of the water temperature inversion layer was different. As a result of horizontal water temperature slope analysis of the water temperature inversion zone, maximum 0.23℃/km was obtained and the mean was 0.06℃/km. The role of water temperature inversion as an indicator to determine the formation of water front. As a result of the water mass analysis, Jeju Warm Current Water and Tsushima Warm Current Water of high temperature and high salt intruded from the middle to the bottom. In the middle layer occurred as the Yellow Sea Cold Water of low water temperature and low salinity expanded.

계류기구로 관측한 대구시 야간 안정층 특성에 관한 사례연구 (Characteristic of the Nocturnal Inversion Layer observed by Tethersonde in Daegu)

  • 김희종;윤일희;권병혁;허만천
    • 한국환경과학회지
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    • 제11권3호
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    • pp.155-160
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    • 2002
  • Using measured data at Daegu by tethersonde for the period of 1984∼1987, we have investigated the lower atmospheric boundary layer structure including relationships between inversion layer and meteorological factors(wind and temperature), and the inversion strength and inversion height. The inversion layer was defined from the vertical temperature profile and its strength was analyzed with the wind shear as well as the vertical temperature gradient. From October to January, measured inversion layer isn't destroyed, however, in June, after sun rise, it is destroyed by surface heating and mixed layer is developed from surface. According to Pasquill stability classes, the moderately stable cases dominated. It's the larger vertical temperature gradient the lower SBL height. We have introduced B(bulk turbulence scale) which indicated SBL height. It's larger B, the higher SBL height and vice versa. It was noted that the bulk turbulence scale (B) is appropriate to determine the stable boundary layer height.

김해에서 관측한 접지역전층의 특성에 관한 연구 (A Study on the Characteristics of Inversion Layer Observed at Kimhae)

  • 박종길;원경미
    • 한국환경과학회지
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    • 제3권4호
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    • pp.305-315
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    • 1994
  • The field observation was carried out to investigate the characteristics of surface inversion layer at Kimhae using the feild observed date and upper layer meteorological data during 4-5 February 1993. The results of the study can be summarized as follows : The maximum height of surface inversion layer observed at Kimhae is 193m and the height of upper level inversion layer ranges from 2nm to 300m. The surface weather elements was influenced the formation of surface inversion layer. According to the pasquill stability and time variation of temperature with height, both the surface heating from insolation and the disturbance of upper level of inversion layer was influenced the disappearance of inversion layer. And the stability of surface temperature inversion layer generally belongs to the class of F, that of upper level temperature inversion layer commonly to the class of E.

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Temperature Inversion off Wasaka Bay in the East Sea, June of 1995 and 1996

  • Lee Chung-Il;Cho Kyu-Dae;Yun Jong-Hwui
    • 해양환경안전학회지
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    • 제10권1호
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    • pp.55-59
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    • 2004
  • 1995년도 1996년 6월에 실시된 CREAMS 항해 관측 자료를 이용하여 Wasaka bay 연안역의 수온역전 현상을 조사하였다. 수온역전현상은 대부분 20m 이천의 상층부에 위치하였으며, 특히 쓰시마난류와 연안수와의 경계역 부분에 형성되었다. 쓰시마난류는 고온${\cdot}$고염분수의 특징을 가지며, 이러한 고수온은 경계역 부분에서 수온역전 현상을 초래하여 밀도 역전현상을 일으키는 작용을 하는 반면, 고염분은 밀도를 증가시켜 주는 작용을 하여 수온역전에 따른 밀도역전현상을 막아주는 역할을 한다.

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Small CMOS Temperature Sensor Using MOSFETs in the Intermediate-Inversion Region

  • Park, Tai-Soon;Park, Sang-Gyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.1086-1087
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    • 2009
  • A small temperature sensor is designed in a 0.35um CMOS process. Transistors operating in the intermediate inversion region are employed in the core of the sensor. This temperature sensor operates in $-50^{\circ}C{\sim}120^{\circ}C$ with ${\pm}2^{\circ}C$ of accuracy after two-point calibration. This temperature sensor can be placed in the active pixel area of a display panel to measure the temperature of the display panel for temperature compensation.

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Meteorological Factors Affecting Winter Particulate Air Pollution in Ulaanbaatar from 2008 to 2016

  • Wang, Minrui;Kai, Kenji;Sugimoto, Nobuo;Enkhmaa, Sarangerel
    • Asian Journal of Atmospheric Environment
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    • 제12권3호
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    • pp.244-254
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    • 2018
  • Ulaanbaatar, the capital of Mongolia, is subject to high levels of atmospheric pollution during winter, which severely threatens the health of the population. By analyzing surface meteorological data, ground-based LIDAR data, and radiosonde data collected from 2008 to 2016, we studied seasonal variations in particulate matter (PM) concentration, visibility, relative humidity, temperature inversion layer thickness, and temperature inversion intensity. PM concentrations started to exceed the 24-h average standard ($50{\mu}g/m^3$) in mid-October and peaked from December to January. Visibility showed a significant negative correlation with PM concentration. Relative humidity was within the range of 60-80% when there were high PM concentrations. Both temperature inversion layer thickness and intensity reached maxima in January and showed similar seasonal variations with respect to PM concentration. The monthly average temperature inversion intensity showed a strong positive correlation with the monthly average $PM_{2.5}$ concentration. Furthermore, the temperature inversion layer thickness exceeded 500 m in midwinter and overlaid the weak mixed layer during daytime. Radiative cooling enhanced by the basin-like terrain led to a stable urban atmosphere, which strengthened particulate air pollution.

봄철 제주도 서부해역의 수괴 분포와 수온역전 특징 (Distribution of Water Masses and Characteristics of Temperature Inversion in the Western Seas of Jeju Island in Spring)

  • 강소영;문재홍
    • Ocean and Polar Research
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    • 제44권3호
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    • pp.191-207
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    • 2022
  • Using the results of CTD casts made in Spring from 2017 to 2021, in this study we investigated the water mass distribution and occurrence of temperature inversion in the western seas of Jeju Island in spring. The distribution of water masses was characterized by cold and fresh water in the northwest and warm and saline water in the southeast, forming a strong thermohaline front running in the southwest-to-northeast direction. Strong temperature inversion mainly occurred in the frontal boundary when the cold water intrudes beneath the warm water at depths of 30-50 m. Analysis of the mixing ratio demonstrated that Jeju Warm Water is dominantly distributed in the western seas of Jeju Island, but its ratio can be modified depending on the southward extension of Yellow Sea Cold Water (YSCW). Results of in situ measurement showed that in 2020, the YSCW largely expanded to the western seas of Jeju Island, occupying approximately 40 % of the mixing ratio. Due to the expansion of YSCW, a strong thermohaline front was formed in the study area, thereby causing thick and strong temperature inversion. On the other hand, in 2018 the mixing ratio of YSCW was minimum (~18%) during the study period of 2017-2021, and thus a relatively weak frontal boundary was formed, without the occurrence of temperature inversion. The observational results also suggest that the interannual changes of water mass distribution and the associated temperature inversion in the western seas of Jeju Island are closely related with wind-driven Yellow Sea circulation in spring, which is the summer monsoon transition period.

부산연안에서 관측된 저층대기의 특성에 관한 연구 (Study on the Characteristics of Low Level Atmosphere Observed in Pusan Coastal Ares)

  • 전병일;김유근
    • 한국환경과학회지
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    • 제7권2호
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    • pp.195-202
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    • 1998
  • The low level atmospheric obsewation carried out to Investigate magnitude, formation and dissipation of nocturnal surface Inversion layer, also to survey relation to each meterological parameter In Inversion layer at Pusan power plant for Oct. 13, 1996. As coastal area, the surface Inversion layer height was relatively high(186m), and after sunset unstable layer formated firom surface to around 40m, and the Inversion layer was left still in the upper layer. The surface Inversion layer dissipated at 0920LST perfectly. The layer that strong Inversion layer was formated, showed steep variation of potential temperature and wand speed and relative humidity.

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