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31.
In this study, the correlation between simulated and measured radar velocity spectrum width(σv) is investigated. The results show that the dendrites growth zones(DGZs) and needles growth zones(NGZs) mostly contain dendrites(DN) and needles(NE), respectively.Clear σv zones(1.1 < σv(m s–1) < 1.3 and 0.3 < σv(m s–1) < 0.7 for the DGZ and NGZ, respectively) could be identified in the case studies(27 and 28 February 2016) n...  相似文献   
32.
张允汉 《福建地质》1999,18(2):103-107
根据福建省煤炭资源地质特点,结合《煤炭资源地质勘探规范》和《联合国国际储量/资源分类框架》,提出福建省煤炭资源地质勘查方法。  相似文献   
33.
Although significant research efforts have been targeted toward conservation and management of endangered terrestrial flora and fauna, attempts have been limite...  相似文献   
34.
Previous observational studies have estimated anthropogenic aerosol direct radiative forcing over oceans without due consideration of cloudy-sky aerosols.However,when interaction between clouds and aerosols located below or above the cloud level is taken into account,the aerosol direct radiative forcing is larger by as much as 5 W m-2 in most mid-latitude regions in the Northern Hemisphere.  相似文献   
35.
An integrally coupled wave-tide-surge model was developed and then applied to the simulation of the wave-typhoon surge for the typhoon Isewan (typhoon Vera (5915)), which is the strongest typhoon that has struck Japan and caused incalculable damage. An integrally coupled tide-surge-wave model using identical and homogeneous meshes in an unstructured grid system was used to correctly resolve the physics of wave-circulation interaction in both models. All model components were validated independently. The storm surge and wave properties such as the surge height, the significant wave height, wave period and direction were reproduced reasonably under the meteorological forcing, which was reprocessed to be close to the observations. The resulting modeling system can be used extensively for the prediction of the storm surge and waves and the usual barotropic forecast.  相似文献   
36.
The Maenggol Channel and Uldolmok Strait, located on the south-west coast of Korea, have notably strong and complex currents due to tidal effects and to local geological factors. In these areas, electric power has been generated using strong tidal currents, the speed of which is more than 3 m/s during spring tides. The region also provides a shortcut for navigation. These tidal conditions are therefore sometimes useful, but may also cause terrible accidents or severe economic damage, in the absence of accurate information regarding ocean conditions. In April 2014, the passenger ferry MV Sewol capsized in the Maenggol Channel, with 295 passengers killed and 9 still missing. While this was unquestionably a man-made disaster, strong currents were one of the contributing causes. It was also difficult to conduct scuba diving rescue operations given strong current speeds, and accurate prediction of the time when the tide would turn was thus critically needed. In this research, we used the high-resolution coastal circulation forecasting system of KOOS (Korea Operational Oceanographic System) for analysis and simulation of strong tidal currents in such areas with many small islands, using measurements and modeling from this research area. For accurate prediction of tidal currents, small grid size-modeling was needed, and in this study, we identified a suitable grid size that offers efficiency as well as accuracy.  相似文献   
37.
以黄海及其邻区为研究对象 ( 32~ 4 2°N ,1 2 0~ 1 30°E) ,以研究区的空间重力异常、布格重力异常和地震层析成像数据为基础 ,在研究区中分辨出方向各异的主要断裂带并给出它们的分布。对在朝鲜半岛存在的一条近SN向分布的断裂带进行了重点讨论。根据重力数据、莫霍深度分布特点和层析成像的结果 ,认为该断裂带的两侧应属于不同的构造地质单元 ;提出该断裂带与五莲—青岛断裂带和济州岛南缘断裂带一起组成了中朝与扬子块体在黄海海区的边界结合带的认识 ;并推测在三叠纪的晚期 ,沿郯庐断裂带和该断裂带曾分别发生过左旋和右旋走滑。受SN向挤压应力的作用 ,(下 )扬子块体被平移嵌入到中朝块体之中。因此 ,两个块体在海区的结合带为一个巨大的“Z”字型的入构造  相似文献   
38.
Abstract— ESA's Rosetta spacecraft will fly by main‐belt asteroid 2867 Steins on September 5, 2008. We obtained new visible wavelength spectra of 2867 Steins on December 19, 2006 (UT), using the Palomar 5 m telescope and the facility Double Spectrograph. Two sets of spectra, taken ~3 h apart, one half of the rotation period for 2867 Steins, show it to be an E‐type asteroid. The asteroid displays a 0.50 μm feature that is considered diagnostic of the E(II) sub‐class, but is deeper than any previously observed E‐type. This feature is most likely due to the presence of oldhamite (CaS) on the asteroid's surface. Also, the observed Steins spectra are far redder than any other known E‐types. There is potential evidence for heterogeneity on hemispheric scales, one side of the asteroid appearing to be significantly redder than the other. No known recovered meteorite sample matches the unusual spectra of 2867 Steins, but the closest analog would be similar to an enstatite achondrite (aubrite).  相似文献   
39.
The effects of sea surface temperature(SST) data assimilation in two regional ocean modeling systems were examined for the Yellow Sea(YS). The SST data from the Operational Sea Surface Temperature and Sea Ice Analysis(OSTIA) were assimilated. The National Marine Environmental Forecasting Center(NMEFC) modeling system uses the ensemble optimal interpolation method for ocean data assimilation and the Kunsan National University(KNU) modeling system uses the ensemble Kalman filter. Without data assimilation, the NMEFC modeling system was better in simulating the subsurface temperature while the KNU modeling system was better in simulating SST. The disparity between both modeling systems might be related to differences in calculating the surface heat flux, horizontal grid spacing, and atmospheric forcing data. The data assimilation reduced the root mean square error(RMSE) of the SST from 1.78°C(1.46°C) to 1.30°C(1.21°C) for the NMEFC(KNU) modeling system when the simulated temperature was compared to Optimum Interpolation Sea Surface Temperature(OISST) SST dataset. A comparison with the buoy SST data indicated a 41%(31%) decrease in the SST error for the NMEFC(KNU) modeling system by the data assimilation. In both data assimilative systems, the RMSE of the temperature was less than 1.5°C in the upper 20 m and approximately 3.1°C in the lower layer in October. In contrast, it was less than 1.0°C throughout the water column in February. This study suggests that assimilations of the observed temperature profiles are necessary in order to correct the lower layer temperature during the stratified season and an ocean modeling system with small grid spacing and optimal data assimilation method is preferable to ensure accurate predictions of the coastal ocean in the YS.  相似文献   
40.
In this study,singular vectors related to a heavy rainfall case over the Korean Peninsula were calculated using the fifth-generation Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model (MM5) adjoint modeling system.Tangent linear and adjoint models include moist physical processes,and a moist basic state and a moist total energy norm were used for the singular-vector calculations.The characteristics and nonlinear growth of the first singular vector were analyzed,focusing on the relationship between the basic state and the singular vector.The horizontal distribution of the initial singular vector was closely related to the baroclinicity index and the moisture availability of the basic state.The temperature-component energy at a lower level was dominant at the initial time,and the kinetic energy at upper levels became dominant at the final time in the energy profile of the singular vector.The nonlinear growth of the singular vector appropriately reflects the temporal variations in the basic state.The moisture-component energy at lower levels was dominant at earlier times,indicating continuous moisture transport in the basic state.There were a large amount of precipitation and corresponding latent heat release after that period because the continuous moisture transport created favorable conditions for both convective and nonconvective precipitation.The vertical propagation of the singular-vector energy was caused by precipitation and the corresponding latent heating in the basic state.  相似文献   
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