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1.
基于ROMS和4DVAR的沿轨与网格化SSH数据同化效果评价 总被引:1,自引:1,他引:0
Remote sensing products are significant in the data assimilation of an ocean model. Considering the resolution and space coverage of different remote sensing data, two types of sea surface height(SSH) product are employed in the assimilation, including the gridded products from AVISO and the original along-track observations used in the generation. To explore their impact on the assimilation results, an experiment focus on the South China Sea(SCS) is conducted based on the Regional Ocean Modeling System(ROMS) and the four-dimensional variational data assimilation(4 DVAR) technology. The comparison with EN4 data set and Argo profile indicates that, the along-track SSH assimilation result presents to be more accurate than the gridded SSH assimilation, because some noises may have been introduced in the merging process. Moreover, the mesoscale eddy detection capability of the assimilation results is analyzed by a vector geometry–based algorithm. It is verified that, the assimilation of the gridded SSH shows superiority in describing the eddy's characteristics, since the complete structure of the ocean surface has been reconstructed by the original data merging. 相似文献
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DEVELOPMENTSTRATEGIESOFWATERANDLANDRESOURCESINTHEHEXIREGION,CHINA肖洪浪,高前兆,李福兴DEVELOPMENTSTRATEGIESOFWATERANDLANDRESOURCESINTHE... 相似文献
3.
This article describes the impact of satellite altimeter data on the simulations of sea level variability (SLV) by a nonlinear reduced gravity model of the entire Indian Ocean. The model has been forced by 6-hourly analyzed wind stress data containing SSM/I observations and has been able to produce realistic circulation features. However, SLV values observed by Topex/Poseidon altimeter do not fit these simulations because of imperfect initial data. Hence an attempt has been made to initialize the model using altimeter data. The initialized model-generated SLVvalues have been compared with SLV derived by altimeter for monsoon as well as nonmonsoon months of 1996. Experimental runs have been performed for 10 days, 20 days, and one month. It has been found that the initialized model results on the final day of these experiments are in very good agreement with altimeter data of the same day. It is thus possible, in principle, to hindcast and forecast sea level variations in the time scale of 10 days to one month with the availability of good quality wind data for forcing the model and altimeter observations of sea level for initializing it. 相似文献
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Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented, which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake. And secondly, with a model forming idea oftransport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference, a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory.Meanwhile, the model was applied to model potassium/magnesium transport in Qarhan Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/Magnesium in the mining of salt deposits in Qarhan Salt Lake. 相似文献
7.
LI Wenpeng 《《地质学报》英文版》2008,(5)
Firstly,the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory.The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented,which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake.And secondly,with a model forming idea of transport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference,a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory. Meanwhile,the model was applied to model potassium/magnesium transport in Qarban Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/ Magnesium in the mining of salt deposits in Qarban Salt Lake. 相似文献
8.
李云星 《测绘与空间地理信息》2008,(1)
1∶500,1∶1000,1∶2000系列数字化测绘产品按其生产工艺和用途的不同其精度规格也不尽相同,但产品的精度状况始终是测绘生产部门与用户所关心的问题。本文列举了现行有关规范的相关精度指标、规格,并结合产品的用途、特点和测绘生产的实际,简要阐述精度目标的控制与实现过程,对测绘实际工作有一定的参考价值。 相似文献
9.
主要从大比例尺航测成图质量评定角度出发,提出了既要满足相应规范和用户要求,又要最大限度的发挥航测成图的优势,对产品质量做出公正、客观、正确的质量评价方法。 相似文献
10.
西北旅游落后现状的突破及列车旅游的新思路--兼论"西部之星"旅游列车的产品设计 总被引:1,自引:0,他引:1
近几年,西北地区的旅游业虽然取得了很大的成绩,但其发展相对于东部地区却显得落后,其主要原因之一就是西北地区的旅游资源过于分散,景点间距过大,由此导致游览行程过长,游览内容单薄,这在客观上影响了游客的选择。而与此同时,在国外,列车旅游早已作为各国旅游业的重要旅游产品为世人所熟知。文章从分析我国西北旅游业发展的现状入手,针对景点分散这一制约我国西部旅游业发展的客观不利因素,肯定了开发旅游列车产品的思路。作者以西北地区为例,结合目前我国旅游专列发展现状,提出开通“西部之星”旅游列车的构想,并进行了初步的设计。 相似文献