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111.
This paper introduces the process of development and practical use implementation of an advanced river management system for supporting integrated water resources management practices in Asian river basins under the framework of GEOSS Asia water cycle initiative (AWCI). The system is based on integration of data from earth observation satellites and in-situ networks with other types of data, including numerical weather prediction model outputs, climate model outputs, geographical information, and socio-economic data. The system builds on the water and energy budget distributed hydrological model (WEB-DHM) that was adapted for specific conditions of studied basins, in particular snow and glacier phenomena and equipped with other functions such as dam operation optimization scheme and a set of tools for climate change impact assessment to be able to generate relevant information for policy and decision makers. In situ data were archived for 18 selected basins at the data integration and analysis system of Japan (DIAS) and demonstration projects were carried out showing potential of the new system. It included climate change impact assessment on hydrological regimes, which is presently a critical step for sound management decisions. Results of such three case studies in Pakistan, Philippines, and Vietnam are provided here.  相似文献   
112.
Using diagnostic analyses and an AGCM simulation, the detailed mechanism of Indian Ocean Dipole (IOD) influence on the early winter Tibetan Plateau snow cover (EWTPSC) is clarified. In early winter of pure positive IOD years with no co-occurrence of El Ni?o, the anomalous dipole diabatic heating over the tropical Indian Ocean excites the baroclinic response in the tropics. Since both baroclinic and barotropic components of the basic zonal wind over the Arabian Peninsula increase dramatically in early winter due to the equatorward retreat of the westerly jet, the baroclinic mode excites the barotropic Rossby wave that propagates northeastward and induces a barotropic cyclonic anomaly north of India. This enables the moisture transport cyclonically from the northern Indian Ocean toward the Tibetan Plateau. The convergence of moisture over the plateau explains the positive influence of IOD on the EWTPSC. In contrast, the basic zonal wind over the Arabian Peninsula is weak in autumn. This is not favorable for excitation of the barotropic Rossby wave and teleconnection, even though the IOD-related diabatic heating anomaly in autumn similar to that in early winter exists. This result explains the insignificant (significant positive) partial correlation between IOD and the autumn (early winter) Tibetan Plateau snow cover after excluding the influence of ENSO. The sensitivity experiment forced by the IOD-related SST anomaly within the tropical Indian Ocean well reproduces the baroclinic response in the tropics, the teleconnection from the Arabian Peninsula, and the increased moisture supply to the Tibetan Plateau. Also, the seasonality of the atmospheric response to the IOD is simulated.  相似文献   
113.
Akara gold mine in north-central Thailand is situated within the Loei-Phetchabun-Nakhon Nayok volcanic belt. The roughly north-south trending, Permo-Triassic volcanic rocks earlier mapped by Thailand Department of Mineral Resources were re-mapped and samples were collected from the main active open pit. Forty-four samples were petrographi-cally classified and geochemically analyzed to docu-ment their stratigraphy. Two types of volcanic rocks are recognized, namely coherent and non-coherent units, in which the former is older on the basis of stratigraphic succession. Several lines of evidence suggest that the studied rocks occurred nearby the volcanic edifices and were dominated by debris flows of submarine environment.  相似文献   
114.
TRMM/PR资料在中尺度模式中的应用   总被引:3,自引:3,他引:0  
将中尺度非静力模式MM5中的积云参数化Grell方案作了改进,使它含液态水含量,并用该模式对1998年6月29日08:00~30日08:00(北京时,下同)和7月1日08:00~2日08:00发生在淮河流域的两次特大暴雨进行数值模拟研究,同时通过采用不同高度上的Z—qr关系式将TRMM/PR(Tropical Rainfall Measuring Mission/Precipitation Radar)雷达得到的反射率资料计算出比含水量qr,然后用qv=qv qr取代原模式中的比湿qv。结果表明,将TRMM/PR雷达资料加入模式后,由于PR雷达具有较高的空问分辨率,能够很好地反映中小尺度系统的空间结构,使湿度值接近实际,缩短了中尺度系统的发展时间,使得模拟出来的降雨强度、雨量中心位置以及雨带形状更接近实况。  相似文献   
115.
Concentrations of radon 222Rn andair pollutants, meteorological parametersnear the surface and vertical profiles of meteorological elements were measured atUchio (Okayama City, Okayama Prefecture, Japan) 12 km north from the coast ofthe Inland Sea of Japan. In the nighttime, the 222Rn concentration increased in the case of weak winds, but did not increase as much in the case of moderate or strong winds, as had been expected. In the daytime, the 222Rn concentrationheld at a slightly higher than average level for the period from sunrise to about 1100 JST. It is considered that this phenomenon is due to a period of morning calm, that is, a transition period from land breeze to sea breeze.NO, which is sensitive to traffic volume,brought information concerning advection.Oxidant concentrations,which reflect the availability of sunlight,acted in the reverse manner to 222Rnconcentrations. Thus, a set of 222Rn and air pollutants could provide useful information regarding the local conditions of the atmospheric boundary layer.  相似文献   
116.
Petrographic observations, and mineralogical and geochemical analyses, have revealed that the Hegenshan ophiolite is of mid-ocean ridge origin and has been subjected to dynamothermal metamorphism at medium P/T conditions. The metamorphism is characterized by a prograde change in paragenesis from the greenschist to epidote-amphibolite facies, with peak temperature conditions of 570-640°C at pressures of 4-10 kbar. The amphiboles formed by this metamorphism show K-Ar ages of 110-130 Ma. The metamorphic conditions and K-Ar ages suggest that the Hegenshan ophiolite is located at the suture between the Siberian and North China continental blocks, where the continental collision in this area took place in middle Mesozoic time. Given the temporal and spatial distribution of the igneous activity around the Da Hinggan Ling Mountains, it is suggested that the extensive Yanshanian magmatism in this region resulted predominantly from a southward subduction of an oceanic plate prior to collision. Alternatively, it may possibly have resulted from the collision itself, at the final stage.  相似文献   
117.
In the Tokyo metropolis many geological surveys are carried out in conjunction with building construction work and urban base improvement undertakings. Furthermore, the Institute of Civil Engineering (ICE) of the Tokyo Metropolitan Government (TMG) has been conducting surveys on urban geology, land subsidence, and geodetics. Thus, ICE of TMG keeps a lot of geological data. In order to plan for a more effective use of these data, the Geotechnical Data Information System of Tokyo Metropolitan Government was organized in 1985, and since 1986, it has become fully implemented.This Geotechnical Data Information System has incorporated a relational data base into a mainframe computer, the NEC ACOS System 430, and as of March 1989 it can retrieve and graphically present borehole, deep-well, and groundwater data.The authors wish to introduce in this article the organizational structure of the Geotechnical Data Information System of TMG, a summary of the data base system, standards of input data, and applicable examples of the data base.  相似文献   
118.
In the system Na2CO3-MgO-SiO2-H2O a new sodium magnesium silicate was synthesized under hydrothermal conditions; 450–600 ° C and 300–1000 Kg/cm2. The structure of the specimen was determined by X-ray powder methods, and its properties were studied by chemical, infrared and TG analyses. The specimen has a triple chain structure (space group, C2/c) with the ideal chemical composition, 4 (Na2Mg4Si6O16(OH)2) and lattice parameters, a= 10.152(2), b=27.137(4), c=5.276(1) Å, and = 106.97(3) °.The essential feature of the structure is shown by the presence of SiO4 tetrahedra linked to form chains which have three times the width of those in pyroxene. These triple chains have a periodicity, 5.27 Å, along their lengths, and are bonded to each other laterally by the brucite layer made up by eight Mg cations and sandwiched between two inward pointing bands of tetrahedra. These units are linked back to back by cations (Mg or Na) in the Na(2) site and by a large cation (Na) at the Na(1) site.  相似文献   
119.
Along the margins of the Japanese Islands there are large belts of mafic rocks that are now deeply buried. The origin of the belts is unknown: they could be either remnants of oceanic crust now trapped within the continental area, or they could be igneous bodies of continental origin. In this paper a discussion of this problem is given and new results presented.  相似文献   
120.
将中尺度非静力模式MM5中的积云参数化Grell方案作了改进,使它含有降水云的云水,即雨水含量,并用该模式对1998年6月29日08时-30日08时(北京时)和1998年7月1日08时-2日08时(北京时)发生在淮河流域的两次特大暴雨进行数值模拟研究,同时通过采用R-qr关系将TRMM/PR(Tropical Rainfall MeasuringMission/Precipition Radar)得到的降水强度资料R计算出比含水量qr,然后用q'v=qv+qr取代原模式中的比湿qv。结果表明将TRMM/PR资料加入模式后,由于PR雷达具有较高的空间分辨率,能够很好地反映中小尺度系统的空间结构,能够使湿度值接近实际,缩短了中尺度系统的发展时间,使得模拟出来的降雨强度、雨量中心位置以及雨带形状更接近实况。  相似文献   
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