检索结果-南通市图书馆

latitudinal variation OF DEEP SCATTERING LAYER IN THE WESTERN PACIFIC

Journal of Hydrodynamics 2004年第5期16卷 571-581页

作者： LUELian-gang, QIAOFang-li YUANYe-li KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

The acoustic Echo Intensity (EI) was recorded with 38k shipborne AcousticDoppler Current Profiler (AD-CP) in the Western Pacific in four cruises between Sept. 2001 and Oct.2002. The main Deep Scattering Layer (DSL) was observed at 400m-600 m depth in the four cruises. Thelatitudinal variation of the main DSL, which has high level of back-scatter strength (BS) at highlatitude, is prominent during both nighttime and daytime. The influences of environmental conditionson the DSL are discussed. Since high-oxygen water in the north is a friendly environment of marineanimals which form the main DSL, more animals are expected to aggregate in the 400dbars-600dbarslayer in the north. Dissolved Oxygen (DO) is the principal factor that causes the main DSL to varywith latitude, and its spatial distributions result from formation and transport of North PacificIntermediate Water (NPIW).

关键词： deep scattering layer latitudinal variation north pacific intermediatewater (NPIW) acoustic doppler current profiler (ADCP) dissolved oxygen

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Inertial gravity wave parameters for the lower stratosphere from radiosonde data over China

引用

Science China Earth Sciences 2017年第2期60卷 328-340页

作者： BAI ZhiXuan BIAN JianChun CHEN HongBin CHEN Lei Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049China Northwest Institute of Nuclear Technology Urumqi 841700China

Characterization of gravity wave （GW） parameters for the stratosphere is critical for global atmospheric circulation models. These parameters are mainly determined from measurements. Here, we investigate variation in inertial GW activity with season and latitude in the lower stratosphere （18-25 km） over China, using radiosonde data with a high vertical resolution over a 2-year period. Eight radiosonde stations were selected across China, with a latitudinal range of 22°-49°N. Analyses show that the GW energy in the lower stratosphere over China has obvious seasonal variation and a meridional distribution, similar to other regions of the globe. The GW energy is highest in winter, and lowest in summer; it decreases with increasing latitude. Velocity perturbations with longitude and latitude are almost the same, indicating that GW energy is horizontally isotropic. Typically, 85% of the vertical wavelength distribution is concentrated between elevations of 1 and 3 km, with a mean value of 2 kin; it is almost constant with latitude. Over 80% of all the horizontal wavelengths occur in the range 100-800 km, with a mean value of 450 km; they show a weak decrease with increasing latitude, yielding a difference of about 40 km over the 22°-49°N range. The ratio of horizontal wavelength over vertical wavelength is about 200：1, which implies that inertial GWs in the lower stratosphere propagate along nearly horizontal planes. Ratios of their intrinsic frequency to the Coriolis parameter decrease with increasing latitude; most values are between 1 and 2, with a mean value of 1.5. Study of the propagation directions of GW energy shows that upward fractions account for over 60% at all stations. In contrast, the horizontal propagation direction is significantly anisotropic, and is mainly along prevailing wind directions; this anisotropy weakens with increasing latitude.

关键词： Inertial gravity wave Lower stratosphere Energy density Intrinsic frequency Propagation direction Seasonalvariation latitudinal variation Velocity perturbations

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Meiofauna Distribution in Intertidal Sandy Beaches Along China Shoreline(18?–40?N)

引用

Journal of Ocean University of China 2016年第1期15卷 19-27页

作者： HUA Er ZHANG Zhinan ZHOU Hong MU Fanghong LI Jia ZHANG Ting CONG Bingqing LIU Xiaoshou College of Marine Life Science Ocean University of China

In this study,the distribution pattern of meiofauna from nine sandy beaches at six latitudinal gradients along Chinese coast between 18 and 40?N was studied on their meiofauna abundance to examine the effect of latitudinal *** general,meiofauna abundance was lower in four subtropical beaches in Xiamen(24?N) and Zhoushan(29?N) than that in other *** abundance differed little between tropical and temperate *** taxonomic structure of meiofauna showed a dominance of nematode in colder *** relative composition of turbellarians and polychaetes increased in warmer *** addition to latitudinal gradient,salinity,oxygenation,sediment grain size affect also the meiofauna latitudinal *** for horizontal distribution,the highest meiofauna abundance was found in low tidal zone at tropical beaches,and in middle tidal zone at temperate *** horizontal distribution of meiofauna was controlled by both physical and biotic factors including feeding and anthropogenic *** meiofauna abundance exhibited a horizontal difference,the composition of meiofaunal main taxa was unanimous horizontally at all beaches at the same sampling latitude.

关键词： meiofauna sandy beach abundance horizontal distribution latitudinal variation China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ground magnetic characteristics of the storm-time ring current Asymmetry

Ground magnetic characteristics of the storm-time ring curre...

引用

中国科学院地质与地球物理研究所2008学术年会

作者： WU YingYan~(1+),XU WenYao~1,CHEN GengXiong~1,CHEN Bo~(1,2) & LIU XiaoCan~(1,2) 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China

Using the minute data of the H component of geomagnetic field from the 20°E magnetic meridian chain and the 30°N magnetic latitudinal chain,the temporal evolution characteristics of the equatorial ring current during the storm on November 7—10,2004 are *** is indicated that the UT-MLT and UT-MLAT graphics extremely exhibit the local time distribution,latitudinal variation and temporal evolution of the H *** results show:(1)The UT-MLT contour clearly shows the increasing of the H component mostly around noon during the initial phase,representing the geomagnetic effect from the magnetopause current *** the main phase,most negative values of the H component appear around the dusk-side,indicating the dawn-dusk asymmetric distribution of the ring current. (2)The contour of UT-MLAT suggests the latitudinal variation of the H component decreasing with the enhancement of the latitudes during geomagnetic storm,which is in good agreement with the D *** latitudinal variations provide a new sight for describing the temporal characteristics of the intensity of the storm-time ring current.(3)Both the contours of UT-MLT and UT-MLAT are useful to monitor the space-time distribution of the equatorial ring current.

关键词： geomagnetic storm ring current dawn-dusk asymmetry latitudinal variation

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：