全文获取类型
收费全文 | 91篇 |
免费 | 1篇 |
国内免费 | 4篇 |
专业分类
测绘学 | 3篇 |
大气科学 | 6篇 |
地球物理 | 16篇 |
地质学 | 18篇 |
海洋学 | 22篇 |
天文学 | 24篇 |
自然地理 | 7篇 |
出版年
2021年 | 1篇 |
2020年 | 3篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 1篇 |
2015年 | 7篇 |
2014年 | 3篇 |
2013年 | 3篇 |
2011年 | 5篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 4篇 |
2004年 | 10篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1995年 | 3篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1986年 | 2篇 |
1983年 | 3篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有96条查询结果,搜索用时 31 毫秒
51.
Yosuke?FujiiEmail author Shiro?Ishizaki Masafumi?Kamachi 《Journal of Oceanography》2005,61(4):655-662
Two kinds of nonlinear constraints, not previously studied in oceanography, have been adopted with the Preconditioned Optimizing Utility for Large-dimensional analyses (POpULar) in a three-dimensional oceanic variational analysis in the equatorial Pacific. One is the constraint for the variational Quality Control (QC) procedure and the other is used to avoid density and temperature inversions. Estimation of the large heat content anomaly in the upper ocean related to El Nino and La Nina phenomena is improved with the variational QC. For example, it prevents unusual but correct observation data on the thermocline deepening in the 1997/98 El Nino from being ignored. As a result, it improves the temperature field estimation in the eastern equatorial Pacific. The constraint for avoiding inversions prevents the low salinity layer at the surface and the barrier layer in the eastern equatorial Pacific in the El Nino period from being destroyed by the convective adjustment procedure performed after minimizing the cost function. Incorporating nonlinear constraints in variational analyses is thus a strong candidate for increasing the accuracy of analysis. 相似文献
52.
Short-Range Prediction Experiments with Operational Data Assimilation System for the Kuroshio South of Japan 总被引:3,自引:3,他引:3
Masafumi Kamachi Tsurane Kuragano Satoshi Sugimoto Kumi Yoshita Toshiyuki Sakurai Toshiya Nakano Norihisa Usui Francesco Uboldi 《Journal of Oceanography》2004,60(2):269-282
The short-range (one month) variability of the Kuroshio path was predicted in 84 experiments (90-day predictions) using a
model in an operational data assimilation system based on data from 1993 to 1999. The predictions started from an initial
condition or members of a set of initial conditions, obtained in a reanalysis experiment. The predictions represent the transition
from straight to meander of the Kuroshio path, and the results have been analyzed according to previously proposed mechanisms
of the transition with eddy propagation and interaction acting as a trigger of the meander and self-sustained oscillation.
The reanalysis shows that the meander evolves due to eddy activity. Simulation (no assimilation) shows no meander state, even
with the same atmospheric forcing as the prediction. It is suggested therefore that the initial condition contains information
on the meander and the system can represent the evolution. Mean (standard deviation) values of the axis error for all 84 cases
are 13, 17, and 20 (10, 10, and 12) km, in 138.5°E, in the 30-, 60-, and 90-day predictions respectively. The observed mean
deviation from seasonal variation is 30 km. The predictive limit of the system is thus about 80 days. The time scale of the
limit depends on which stage in the transition is adopted as the initial condition. The gradual decrease of the amplitude
in a stage from meander to straight paths is also predicted. The predictive limit is about 20 days, which is shorter than
the prediction of the opposite transition.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
53.
Horizontal and meridional volume transports on timescales from intra-seasonal to interannual in the North Pacific subarctic
region were investigated using a reanalysis dataset for 1993–2001 that was constructed from an assimilation of the TOPEX altimeter
and in situ data into an eddy-permitting North Pacific ocean general circulation model. The barotropic flow is excited along east of
the Emperor Seamounts by the western intensification dynamics. The volume transport of this flow compensates for that across
the interior region east of the Seamounts below the summit depth of the Seamounts. The Oyashio, which is also considered as
a compensation flow for the transport in the whole interior region, includes baroclinic as well as barotropic components.
Baroclinic transports in the whole interior region exceed those in the western boundary region in the upper (200–1000 m) and
lower (2000–5000 m) layers, and the total transport is northward (southward) in the upper (lower) layer. These excesses of
the baroclinic transport are balanced by a vertical transport of the meridional overturn. The meridional overturn has a complementary
relation to the basin-scale baroclinic circulation in the North Pacific subactic region.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
54.
This short survey presents several research and operational developments of ocean data assimilation in the tropical Pacific,
primarily for climate-scale phenomena. Aspects of theoretical error estimations, diagnostics and practical reduced space techniques
are also briefly reported.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
55.
56.
57.
Large-scale thermodynamics of the stratosphere and mesosphere during the major stratospheric warming in 2003/2004 总被引:1,自引:0,他引:1
P. Mukhtarov D. Pancheva B. Andonov N.J. Mitchell E. Merzlyakov W. Singer W. Hocking C. Meek A. Manson Y. Murayama 《Journal of Atmospheric and Solar》2007,69(17-18):2338
The stratosphere–mesosphere response to the major sudden stratospheric warming (SSW) in the winter of 2003/2004 has been studied. The UKMO (UK Meteorological Office) data set was used to examine the features of the large-scale thermodynamic anomalies present in the stratosphere of the Northern Hemisphere. The vertical and latitudinal structure of the genuine anomalies, emphasized by removing the UKMO climatology, has been investigated as well. The features of the stratospheric anomalies have been related to the mesospheric ones in measured neutral winds from radars and temperatures from meteor radars (90 km). It was found that the stratospheric warming spread to the lower mesosphere, while cooling occurred in the upper mesosphere, a feature that may be related to the large vertical scales of the stationary planetary waves (SPWs). It was shown also that the beginning of the eastward wind deceleration in the stratosphere–mesosphere system coincided with the maximum amplification of the SPW1 accompanied by short-lived bursts of waves 2 and 3. 相似文献
58.
Local spatial interaction between neighborhood land-use categories (i.e. neighborhood interaction) is an important factor which affects urban land-use change patterns. Therefore,it is a key component in cellular automata (CA)-based urban geosimulation models towards the simulation and forecast of urban land-use changes. Purpose of this paper is to interpret the similarities and differences of the characteristics of neighborhood interaction in urban land-use changes of different metropolitan areas in Japan for providing empirical materials to understand the mechanism of urban land-use changes and construct urban geosimulation models. Characteristics of neighborhood interaction in urban land-use changes of three metropolitan areas in Japan,i.e. Tokyo,Osaka,and Nagoya,were compared using such aids as the neighborhood interaction model and similarity measure function. As a result,urban land-use in the three metropolitan areas was found to have had similar structure and patterns during the study period. Characteristics of neighborhood interaction in urban land-use changes are quite different from land-use categories,meaning that the mechanism of urban land-use changes comparatively differs among land-use categories. Characteristics of neighborhood interaction reveal the effect of spatial autocorrelation in the spatial process of urban land-use changes in the three metropolitan areas,which correspond with the characteristics of agglomeration of urban land-use allocation in Japan. Neighborhood interaction amidst urban land-use changes between the three metropolitan areas generally showed similar characteristics. The regressed neighborhood interaction coefficients in the models may represent the general characteristics of neighborhood effect on urban land-use changes in the cities of Japan. The results provide very significant materials for exploring the mechanism of urban land-use changes and the construction of universal urban geosimulation models which may be applied to any city in Japan. 相似文献
59.
R. Feldmann C. M. Carollo C. Porciani S. J. Lilly P. Capak Y. Taniguchi O. Le Fèvre A. Renzini N. Scoville M. Ajiki H. Aussel T. Contini H. McCracken B. Mobasher T. Murayama D. Sanders S. Sasaki C. Scarlata M. Scodeggio Y. Shioya J. Silverman M. Takahashi D. Thompson G. Zamorani 《Monthly notices of the Royal Astronomical Society》2006,372(2):565-577
60.