• 제목/요약/키워드: Atmosphere-ocean interaction

검색결과 33건 처리시간 0.023초

ANALYSIS OF THE OCEAN' AND ATMOSPHERE ROLES IN THEIR HEAT INTERACTION WITH USE OF SATELLITE AND VESSEL

  • Grankov, Alexander Georgievich;Mil'shin, Alexander Alexeevich;Krapivin, Vladimir Fedorovich;Golovachev, Sergey Petrovich
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.1001-1002
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    • 2006
  • Special problem emphasized by specialists in the field of analyzing the heat interchanges in the system ocean-atmosphere (SOA) is a necessity of determination of the near-surface atmospheric temperature, which can be only indirectly connected with characteristics of the SOA natural microwave radiation measured from satellites. That is why, the following dilemma is not obvious, but interesting and promised: what is better - to use the satellite methods for retrieving the partial parameters of the SOA or for analysis its state as a whole. To our opinion, this task is similar to the idea recognized by specialists engaged in the heat infrared region (8-12 mcm) of electromagnetic spectrum and its applications, where an intensity of natural infrared radiation (effective radiation) is used as the inherent property (the attribute) of the SOA heat balance. Here we studied important aspects of this problem: a) what medium initiates a heat transfer in the SOA and disturbs its heat balance - the ocean or the atmosphere b) what SOA parameters directly influence on its natural microwave radiation intensity (brightness temperature) measured from satellites? We relate these processes mainly to the synoptic range of time scales enriched by various events in the SOA interface such as the mid-latitude and tropical cyclones.

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지구규모의 탄소 순환 및 물질수지 연구 (Global Carbon Cycle and Budget Study)

  • 권오열
    • 한국환경과학회지
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    • 제5권4호
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    • pp.429-440
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    • 1996
  • A global carbon cycle model (GCCM), that incorporates interaction among the terrestrial biosphere, ocean, and atmosphere, was developed to study the carbon cycling aid global carbon budget, especially due to anthropogenic $CO_2$ emission. The model that is based on C, 13C and 14C mass balance, was calibrated with the observed $CO_2$ concentration, $\delta$13C and $\Delta$14C in the atmosphere, Δ14C in the soil, and $\Delta$14C in the ocean. Also, GCCM was constrained by the literature values of oceanic carbon uptake and CO, emissions from deforestation. Inputs (forcing functions in the model) were the C, 13C and 14C as $CO_2$ emissions from fossil fuel use, and 14C injection into the stratosphere by bomb-tests. The simulated annual carbon budget of 1980s due to anthropoRenic $CO_2$ shows that the global sources were 5.43 Gt-C/yr from fossil fuel use and 0.91 Gt-C/yr from deforestation, and the sinks were 3.29 Gt-C/yr in the atmosphere, 0.90 Gt-C/yr in the terrestrial biosphere and 2.15 Gt-C/yr in the ocean. The terrestrial biosphere is currently at zero net exchange with the atmosphere, but carbon is lost cia organic carbon runoff to the ocean. The model could be utilized for a variety of studies in $CO_2$ policy and management, climate modeling, $CO_2$ impacts, and crop models.

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Extraction of the atmospheric path radiance in relation to retrieval of ocean color information from the TM and SeaWiFS imageries

  • Ahn, Yu-Hwan;Shanmugam, P.
    • 한국GIS학회:학술대회논문집
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    • 한국GIS학회 2004년도 GIS/RS 공동 춘계학술대회 논문집
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    • pp.241-246
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    • 2004
  • The ocean signal that reaches the detector of an imaging system after multiple interactions with the atmospheric molecules and aerosols was retrieved from the total signal recorded at the top of the atmosphere (TOA). A simple method referred to as 'Path Extraction' applied to the Landsat-TM ocean imagery of turbid coastal water was compared with the conventional dark-pixel subtraction technique. The shape of the path-extracted water-leaving radiance spectrum resembled the radiance spectrum measured in-situ. The path-extraction was also extended to the SeaWiFS ocean color imagery and compared with the standard SeaWiFS atmospheric correction algorithm, which relays on the assumption of zero water leaving radiance at the two NIR wavebands (765 and 865nm). The path-extracted water-leaving radiance was good agreement with the measured radiance spectrum. In contrast, the standard SeaWiFS atmospheric correction algorithm led to essential underestimation of the water-leaving radiance in the blue-green part of the spectrum. The reason is that the assumption of zero water-leaving radiance at 755 and 865nm fails due to backscattering by suspended mineral particles. Therefore, the near infrared channels 765 and 865nm used fur deriving the aerosol information are no longer valid for turbid coastal waters. The path-extraction is identified as a simple and efficient method of extracting the path radiance largely introduced due to light interaction through the complex atmosphere carried several aerosol and gaseous components and at the air-sea interface.interface.

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기상-해양 접합모델을 이용한 단기간 대기-해양 상호작용이 한반도 강수에 미치는 영향 연구 (A Study of the Influence of Short-Term Air-Sea Interaction on Precipitation over the Korean Peninsula Using Atmosphere-Ocean Coupled Model)

  • 한용재;이호재;김진우;구자용;이윤균
    • 한국지구과학회지
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    • 제40권6호
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    • pp.584-598
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    • 2019
  • 본 연구에서는 지역 기상-해양 접합모델을 이용하여 2018년 8월 28일부터 30일까지 한반도 서울-경기지역에 내린 강수에 대해 대기-해양 상호작용의 효과를 분석하였다. 지역 기상-해양 접합모델에서 기상모델은 WRF (Weather Research Forecasts)가 사용되었으며, 해양모델은 ROMS (Regional Oceanic Modeling System)가 사용되었다. 단일 기상 모델은 WRF모델만 이용되었으며, ECMWF Re-Analysis Interim 의 해수면온도자료가 바닥경계자료로 사용되었다. 관측자료와 비교하여, 대기-해양 상호작용의 효과가 고려된 접합모델은 서울-경기지역의 강수 및 황해 해수면온도에 대해 공간상관계수가 각각 0.6과 0.84로 이는 지역 기상모델보다 높게 나타났다. 또한, 평균편향오차(MBE, Mean Bias Error)은 각각 -2.32와 -0.62로 지역 기상모델 보다 낮은 오차율을 보였다. 상당온위와 해수면온도 및 역학적 수렴장으로 분석한 대기-해양 상호작용의 효과는 황해 해수면온도의 변화를 유도하였고, 그 변화는 하층대기에서 열적 불안정과 운동학적 수렴대의 차이를 발생시켰다. 열적 불안정과 수렴대는 결과적으로 서울-경기 지역에서 상승운동을 유도하였고, 결과적으로 기상-해양 접합모델에서 모의된 강수가 관측과 더 유사한 공간분포를 나타냈다. 그러나 복잡한 관계에 있는 대기-해양 상호작용의 효과를 더 명확히 파악하기 위해서는 다양한 사례연구와 장기적인 분석이 필요하지만, 본 연구는 기상-해양 상호작용이 강수 예보에 중요성에 대한 또 다른 증거를 제시한다.

영동대설 사례와 관련된 동해상의 현열속과 잠열속 분포 특성 (Characteristics of Sensible Heat and Latent Heat Fluxes over the East Sea Related with Yeongdong Heavy Snowfall Events)

  • 김지언;권태영;이방용
    • Ocean and Polar Research
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    • 제27권3호
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    • pp.237-250
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    • 2005
  • To investigate the air mass modification related with Yeongdong Heavy snowfall events, we examined sensible and latent heat fluxes on the East Sea, the energy exchange between atmosphere and ocean in this study. Sensible and latent heats were calculated by a bulk aerodynamic method, in which NCEP/NCAR reanalysis data and NOAA/AVHRR weekly SST data with high resolution were used. Among winter precipitation events in the Yeongdong region, 19 heavy precipitation events $(1995{\sim}2001)$ were selected and classified into three types (mountain, cold-coastal, and warm types). Mountain-type precipitation shows highly positive anomalies of sensible and latent heats over the southwestern part of the East Set When separating them into the two components due to variability of wind and temperature/ specific Humidity, it is shown that the wind components are dominant. Cold-coastal-type precipitation also shows strong positive anomalies of sensible and latent heats over the northern part and over the central-northern part of the East Sea, respectively. It is shown that the sensible heat anomalies are caused mostly by the decrease of surface air temperature. So it can be explained that cold-coastal-type precipitation is closely related with the air mass modification due to cold air advection over warm ocean surface. But in warm-type precipitation, negative anomalies are found in the sensible and latent heat distributions. From this result, it may be postulated that warm-type precipitation is affected by the internal process of the atmosphere rather than the atmosphere-ocean interaction.

등방성 난류에서 침강하는 무거운 입자의 거동 (On behavior of settling heavy particles in isotropic turbulence)

  • 정재달;여경민;이창훈
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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    • pp.437-440
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    • 2006
  • Particle suspension is frequently observed in many natural flows such as in the atmosphere and the ocean as well as in various engineering flows. Recently, airborne micro or nano-scale particles in atmosphere attract much attention from environmental society since small particle cause serious environmental problems in the industrialized areas. Also, the characteristics of such heavy particles' behavior is quite different from its fluid particles because the inertia force and buoyance force acting on the heavy particles are different than those acting on fluid particles. Therefore, our studies is to investigate the characteristics of the behavior of heavy particles considering the inertia effect with or without gravity effect, but do not consider modification of turbulence by the particles, that is one-way interaction. We carried out direct numerical simulation of isotropic turbulence with particles under the Stokes drag assumption for a spherical particle. These results can be used in the development of a stochastic model for predicting particle's behavior.

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해수면 온도변화에 따른 제주도 후면 흐름구조 변화에 관한 수치연구 (Numerical Studies on the Variation of Flow Structure Due to Sea Surface Temperature at the Lee Side of Jeju Island in the Korean Peninsula)

  • 이순환;박광순
    • 한국지구과학회지
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    • 제27권1호
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    • pp.61-72
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    • 2006
  • 대기-해양의 상호작용과 제주도 후면에서 발생하는 카르만소용돌이행렬의 상관관계를 수치실험을 통하여 분석하였다. 카르만 소용돌이는 한라산의 제한된 높이에서 형성되는 경향을 가지고 있다. 그리고 본 연구에서는 900 hPa고도에서 카르만 소용돌이가 뚜렷이 생성되었다. 카르만소용돌이행렬의 발생초기에는 하나의 소용돌이세포가 나타나고 시간이 경과함에 따라 소용돌이는 이류를 한다. 이때 작은 소용돌이로 분리되는 경향이 있다. 분리된 소용돌이의 강도와 지속시간은 해수면 온도 분포와 밀접한 관계를 가진다. 즉 약한 해수면의 온도경도는 카르만 소용돌이의 지속 시간을 길게 하며, 산 후면의 소용돌이도를 감소시킨다. 강한 해수면 온도경도는 혼합층과 대기하층 수증기량을 증가시키고, 강화된 하층대기 혼합은 산악에 의하여 형성되는 기계적 응력을 감소시키는 경향이 있다.

Impact of Reconstructed Gridded Product of Global Wind/Wind-stress Field derived by Satellite Scatterometer Data

  • Koyama, Makoto;Kutsuwada, Kunio;Morimoto, Naoki
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.309-312
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    • 2008
  • The advent of high resolution products of surface wind and temperature derived by satellite data has permitted us to investigate ocean and atmosphere interaction studies in detail. Especially the Kuroshio extension region of the western North Pacific is considered to be a key area for such studies. We have constructed gridded products of surface wind/wind stress over the world ocean using satellite scatterometer (Qscat/SeaWinds), available as the Japanese Ocean Flux data sets with Use of Remote sensing Observation (J-OFURO). Using new data based on improved algorithm which have been recently delivered, we are reconstructing gridded product with higher spatial resolution. Intercomparison of this product with the previous one reveals that there are some discrepancies between them in short-period and high wind-speed ranges especially in the westerly wind region. The products are validated by not only comparisons with in-situ measurement data by mooring buoys such as TAO/TRITON in the tropical Pacific and the Kuroshio Extension Observation (KEO) buoys, but also intercomparison with numerical weather prediction model (NWPM) products (the NRA-1 and 2). Our products have much smaller mean difference in the study areas than the NWPM ones, meaning higher reliability compared with the NWPM products. Using the high resolution products together with sea surface temperature (SST) data, we examine a new type of relationship between the lower atmosphere and upper ocean in the Kuroshio Extension region. It is suggested that the spatial relation between the wind speed and SST depends upon, more or less, the surrounding oceanic condition.

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