Mean Heat Fluxes at Dok Island

Choi Yong-kyu, Choi Hyo and Lee Yong-hwa

Based on the monthly weather report of Korea Meteorological Administration (KMA) and the daily sea surface temperature (SST) data from the Korean Oceanographic Data Center (KODC) during 2000-2008, mean heat fluxes were estimated at Dok Island. The mean SST ranged from 9.2℃ to 26.2℃, mean air temperature (AT) ranged from 2.5℃ to 27.6℃. The lowest SST was 6.8℃ (January 6, 2003) and the highest SST was 29.0℃ (August 13, 2005). The lowest AT was -4.6℃ (December 6, 2008) and the highest AT was 32.0℃ (August 18, 2007). Net heat flux was transported from the air to the sea surface during March to October and it ranged from 133.7 Wm-2 to 260.5 Wm-2. Long wave radiation was shown to be from 19.8 Wm-2 to 91.5 Wm-2 with the minimum value in July. Sensible heat flux ranged from -29.7Wm-2 to 100.1 Wm-2 with a minimum value in April. Latent heat flux ranged from 15.2 Wm-2 to 89.9 Wm-2. The phase of heat exchange changed from cooling to heating at the start of March and from heating to cooling at the start of November. Using factor analysis, the net heat flux showed a positive relationship in SST, AT and relative humidity and a negative relationship in air pressure and wind in which factor 1 explains 56 % of variation.

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Meteorological Guideline to forecast Asian Dusts in the Korean Peninsula

Moon Yun Seob

In order to predict Asian dust events during the spring season over the Korean peninsula, the meteorological guideline was designed. It is based on various meteorological factors such as the geopotential height, the wind speed and shear, the relative humidity, the potential temperature and vorticity and the planetary boundary layer height. In particular, dust emission source, dust transportation and its intensity were judged by weather analyses of these meteorological factors within the Mesoscale Meteorological Model including some observed remote sensing data of dust aerosols. Consequently, Asian dusts over Seoul in Korea were mainly shown in two paths from two weather types. One, as the most frequent case, is that Asian dusts pass through the center of China to Seoul and the other passes through Manchuria to Seoul. Asian dust concentration at each monitoring site of air quality in Seoul was higher under the weather condition of the strong vorticity between the upper cut-off low and the surface cyclone than that of the surface high and low under the upper jet stream. Above all, the meteorological guideline for Asian dust events is made possible by using the decision-making tree including following factors: the weather maps of U and V types due to development between the cut-off low and surface cyclone related to the upper jet stream, the moving speed and direction of the wind speed and shear on 850 hPa surface, satellite images of dusts and the relationship or the multiple regression between some meteorological factors that are similar to the movement of Asian dusts with the spatial distribution of PM10/PM2.5 concentrations in the WRF-Chem modeling.

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Microfacies analysis and depositional environment of Jahrom Formation from Do Kuhak region in Fars area, South Iran

Babazadeh Seyed Ahmad and Pazooki Ranginlou Shirin

The carbonate sedimentary rocks related to Jahrom Formation are well-exposed in Fars area from south Iran, representing a shallow marine carbonate platform. The Jahrom Formation is rich in green algae and benthic foraminifera which indicates a Late Paleocene-Early Eocene age. The taxa of algal-foraminiferal assemblages known from eastern Neo-Tethys sea in Zagros folded belt from Iran. Petrographic study reveals that the Jahrom Formation is mainly composed of two members containing Lower and Upper Members. The Lower Member consists of an alternation of gray thin and thick limestone and dolomitic limestones and the Upper Member is only composed by cream to gray thick bedded dolomitic limestones. The microfacies include seven main facies which are deposited in platform setting. Based on distribution of benthic foraminifera and biofacies features, three depositional environments such as inner, middle and outer ramps are identified. The inner ramp is characterized by green algae and imperforate foraminifera (miliolids) whereas the middle ramp is represented by diverse assemblage of imperforate and perforate foraminifera together with coral boundstone. The outer ramp is characterized by sparse bioclastic fragments and planktonic foraminifera.

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The Effect of the Jet Stream on Drought-Floods Abrupt Switch during Early Summer of 2011 and on Squall Line 10 August over East China

Sun Jilin, Wu Dexing, Wang Feng and Xing Rufeng

The effect of the jet stream on drought-floods abrupt switch during early summer of 2011 and on the squall line of 10 August over East China was studied by a diagnostic method using NCEP reanalysis data and by numerical simulation analysis using WRF. It was found that the different variation ratio of seasonal meridional temperature gradient over land and ocean changes the jet stream strength greatly in the zonal direction and resulted in an entrance region of jet over the lower and middle reaches of the Yangtze River in late spring and early summer of 2011. Together with favorable water vapor supplied by the subtropical high, the drought-floods event was abruptly switched on. For the squall line which occurred on 10th August over the Yellow Sea near Qingdao, it was found that the strength of the jet varied due to cold advection in the upper levels of the troposphere. Severe convective weather associated with the squall occurred at the right side of the jet entrance area. Thus the jet strength variation can affect the weather of both systems on the mid-range time scale and shorter time scale.

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Modeling and simulation of ship lock based on secondary development

Liang Gui-lan, E Yu-kun and Feng Liang

With the purpose of solving the problem of insufficiency of parametric design of the whole lock and simulation effect, this paper has developed a program based on Solidworks with Visual Basic to realize parametric design of lock model and simulation of the lock. On the basis of analysis of lock structure, the program has realized parametric design of upper lock head, lower lock head and lock chamber by controlling the key sizes of the lock structure and it has reduced repeated works and has improved the efficiency. Take an engineering project as example to examine the result of the program and it matches the objectives well. This program has provided a convenient means to analyze the calculation results and to preview the model.

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Modeling North West Iran’s salt domes on Kent Model

Shiri Tarzam Ali and Rajabi Masoomeh

Salt domes are the important morphogenic factors globally that are found both on land and sea with major metal and non-metallic resources especially hydro-carbonic resources. The southern domes of Iran have been the focus of many researchers in geology disciplines and several studies have been done about them due to being large and having diverse resources including hydro-carbonic resources. In opposition, salt domes in the North West of Iran have not been interesting for researchers and considerable research has not been done about them since they are small and do not have hydro-carbonic resources. Based on this, this study has been done on North-West salt domes of Iran.

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