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1.
I~IOXThe Okinawa Trough is an extending back--arc basin between the East China Sea Shelf andthe Ry'Ukyu Island Arc of Japan. There are widespreadly distributing acid pumice in the troughand a little basalt just in some area of the extending center. There have been some detailed rePOrtsabout the mineralogy and petrochemical feature of the subalkali tholeiite and alkali trachyte in thetrough (Zhai and Gan, 1995; Li et al., 1997; Qin and Zhai, 1988). This paper mainly reportselectron mic… 相似文献
2.
海洋作业渔船管理系统的设计与运行试验 总被引:1,自引:0,他引:1
对渔政管理指挥系统建设项日中的业务软件部分渔船管理系统的设计方案进行了介绍。根据我国渔洋作业渔船的实际管理模式,提出了渔船管理系统设计方案。系统通过网络化的业务处理和管理流程,规范渔船建造、审批、登记以及捕捞许可证发放等管理业务,实现渔船控制指标的统一分配,以控制捕捞业发展规模和保护我国的渔业资源。系统以Microsoft VB6.0,Delphi6.0开发,在Window98/2000/XP环境下运行。通过运行试验,对系统运行环境进行了评估,为渔政管理信息化的建设、系统升级提供了经验和技术依据。 相似文献
3.
土壤热异常影响地表能量平衡的个例分析和数值模拟 总被引:6,自引:0,他引:6
The statistical relationship between soil thermal anomaly and short-term climate change is presented based on a typical case study. Furthermore, possible physical mechanisms behind the relationship are revealed through using an off-line land surface model with a reasonable soil thermal forcing at the bottom of the soil layer.In the first experiment, the given heat flux is 5 W m-2 at the bottom of the soil layer (in depth of 6.3 m)for 3 months, while only a positive ground temperature anomaly of 0.06℃ can be found compared to the control run. The anomaly, however, could reach 0.65℃ if the soil thermal conductivity was one order of magnitude larger. It could be even as large as 0.81℃ assuming the heat flux at bottom is 10 W m-2. Meanwhile, an increase of about 10 W m-2 was detected both for heat flux in soil and sensible heat on land surface, which is not neglectable to the short-term climate change. The results show that considerable response in land surface energy budget could be expected when the soil thermal forcing reaches a certain spatial-tem poral scale. Therefore, land surface models should not ignore the upward heat flux from the bottom of the soil layer. Moreover, integration for a longer period of time and coupled land-atmosphere model are also necessary for the better understanding of this issue. 相似文献
4.
WU Yongfu & XU Jiyao Laboratory for Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2005,48(10)
Gravity waves play a significant role in establishing the large-scale circulation and structure of the middle atmosphere. Through gravity wave saturation proc-esses, such motions are believed to cause turbulence, resulting in divergence of momentum flux and the diffusion of heat and constituents in the meso-sphere[1,2]. The mechanisms that contribute signifi-cantly to the gravity wave saturation are thought to be the dynamical and convective instabilities[3]. However, it is difficult to distin… 相似文献
5.
塔中古溶洞见证晚奥陶世抬升幅度 总被引:2,自引:0,他引:2
塔中隆起区上奥陶统良里塔格组灰岩与桑塔木组砂—粉砂岩之间为不整合接触,昭示着这两个组沉积期之间存在一次历时约百万年的区域性构造抬升事件。中古31井良里塔格组三段的4 125.6~4 133.9 m井段为垮塌型溶洞沉积,洞顶距良里塔格组二段顶部190.6 m,溶洞中角砾状充填物主要来自良里塔格组洞壁本身的礁相灰岩,且见数厘米厚的暗河流水沉积纹层,未发现源于其它时代的颗粒混杂其间。这一事实指证了溶洞的形成和充填时代均为良里塔格组沉积之后、桑塔木组覆盖之前的晚奥陶世凯迪中期。具溶蚀力的淡水潜流带的深度一般不低于周围的海平面,由此可推断出该井区这次抬升出海平面之上的高度,即使忽略良里塔格组顶部可能经地表剥蚀的良里塔格组一段,抬升出水面部分至少也应该有190 m,藉生态地层学恢复洞壁礁灰岩沉积时的海水深度约为30 m±,因此总抬升幅度至少能达到220 m。 相似文献
6.
局地云量变化气候效应的数值模拟 总被引:3,自引:3,他引:3
本文用统计得到的东半球夏季平均云量资料,利用改进的云-辐射计算模式,在三维有限区域模式中模拟局地云量变化的气候效应。模拟结果表明,高原地区和热带辐合带云量变化造成的气候效应都主要表现在青藏高原地区。在低反照率时,高原地区云量减少使该地区地表加热,引起高低空气压系统加强;高反照率时结果相反。热带辐合带云量减少会引起青藏高原地区降温和气压系统减弱。 相似文献
7.
A two-layer primitive equation model is developed in this paper. The capabilities of this model aretested by the use of multiyearly averaged January and July sea surface level pressure fields and windfields which can be diagnosed from the pressure fields. The results show that the ocean surface currentsand undercurrents in the second layer driven by the sea surface wind and the sea surface pressure areclose to the observation. The results are also compared with that of the IAP OGCM and the OSUOGCM. 相似文献
8.
Main features of regional circulation variation during onset of the south china sea monsoon in 1998 总被引:4,自引:0,他引:4
1.IntroductionTheAsiansummermonsoonconsistsoftwosystems,i.e.,theSouthAsianmonsoonandtheEastAsianmonsoon.TheSouthChinaSea(SCS)monsoonisoneoftheimportantsubsystemsoftheEastAsianmonsoon.IthaslongbeenconcernedabouttherelationshipoftheSCSmonsoonwithchangesofthegeneralcirculationandweatherpatternsinadjacentregions.TaoandChen(1987)suggestedthattheonsetoftheAsiansummermonsoonstartsfirstinthenorthernSCSusuallyinmid--May,thenpropagatesnorthwardtothemainlandofChinaandthewesternPacificsouthofJap… 相似文献
9.
10.
A numerical study of tropospheric ozone in the springtime in East Asia 总被引:11,自引:0,他引:11
The Models-3 Community Multi-scale Air Quality modeling system (CMAQ)coupled with the Regional Atmospheric Modeling System (RAMS)is applied to East Asia to study the transport and photochemical transformation of tropospheric ozone in March 1998.The calculated mixing ratios of ozone and carbon monoxide are compared with ground 1evel observations at three remote sites in Japan and it is found that the model reproduces the observed features very well.Examination of several high episodes of ozone and carbon monoxide indicates that these elevated levels are found in association with continental outflow,demonstrating the critical role of the rapid transport of carbon monoxide and other ozone precursors from the continental boundary layer.In comparison with available ozonesonde data,it is found that the model-calculated ozone concentrations are generally in good agreement with the measurements,and the stratospheric contribution to surface ozone mixing ratios is quite limited. 相似文献