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991.
A. I. Obzhirov N. L. Pestrikova G. I. Mishukova V. F. Mishukov A. K. Okulov 《Russian Meteorology and Hydrology》2016,41(3):205-212
The spatial distribution of methane content and methane fluxes in the water in the north-western part of the Sea of Japan, in the Kuril basin of the Sea of Okhotsk, and in the near-Kuril part of the Pacific Ocean is studied using the data of marine research expeditions in 2005, 2010, and 2011. The studies revealed the significant variability of the methane flux depending on the source presence and on the sea surface conditions. The high emission of methane from water to the atmosphere is registered in the areas where its concentration exceeds the equilibrium values with the atmosphere. The use of the model of computation of the fields of currents and contaminant transport for the investigated water area enabled explaining the formation of the high concentration of methane in the center of vortices in the zones of sea water convergence in the water areas under study. 相似文献
992.
O. A. Razorenova 《Russian Meteorology and Hydrology》2016,41(1):1-9
Average long-term fields of geopotential gradients in the middle and upper troposphere and temperature gradients and geopotential Laplacian in the middle troposphere in the Northern Hemisphere in winter are analyzed. Based on the analysis of the distribution of the maximum values of gradients, the average long-term position of upper-level frontal zones and their axial lines was determined. Their spatial distribution is analyzed from the point of view of interaction between thermobaric fields over different regions of the globe. Average long-term parameters of upper-level frontal zones in the middle troposphere are presented. Average long-term fields of wind speed in the middle and upper troposphere are investigated. It is demonstrated that the zones of the maximum values of wind speed agree well with the position of separated upper-level frontal zones. 相似文献
993.
Wenpo Shan Peng Yang Haixia Lu Kefeng Ma Zhixin Huang 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(5):451-458
Surface ozone, NO, NO2, and NO x were measured at a coastal site (Shihua) and a nearby inland site (Zhujing) in suburban Shanghai for the whole year of 2009. More days with ozone pollution in a longer time range were observed at the coastal site than the inland site. The diurnal variations of NO x concentrations were obviously higher at Zhujing station, while those of ozone concentrations were higher at Shihua station, indicating their different air pollution conditions. Coastal wind has significant influence on the levels and characteristics of the air pollutants. The ozone concentrations during maritime winds (MW) were much higher than those during continental winds (CW) at each of the site, while the NO and NO2 concentrations were both opposite. The ozone concentrations at Shihua station were much higher than those at Zhujing station, while the NO and NO2 concentrations were both opposite. The ozone concentrations at both of the two sites showed a distinct “weekend effects” and “weekdays effects” patterns during CW and MW, respectively. Correlation analysis of the pollutants showed that, the compounds during MW were more age than those during CW, and the compounds at Shihua were more age than those at Zhujing. The air pollutions at both of the two sites are mainly associated with the pollutants emitted in this region instead of long range transport. 相似文献
994.
Prasanta Kumar Bal Andimuthu Ramachandran Kandasamy Palanivelu Perumal Thirumurugan Rajadurai Geetha Balakrishnan Bhaskaran 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(5):519-519
The author “Bhaski Bhaskaran” and his affiliation “Fujitsu Laboratory of Europe, Middlesex, UK” should be replaced by “Balakrishnan Bhaskaran”, “Fujitsu Laboratories of Europe Limited, Hayes Park, Middlesex, UK”, respectively.The corrected name and affiliation are shown in this erratum. 相似文献
995.
Keunhee Han JunTae Choi Chansoo Kim 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(5):495-507
As the 2018 Winter Olympics are to be held in Pyeongchang, both general weather information on Pyeongchang and specific weather information on this region, which can affect game operation and athletic performance, are required. An ensemble prediction system has been applied to provide more accurate weather information, but it has bias and dispersion due to the limitations and uncertainty of its model. In this study, homogeneous and nonhomogeneous regression models as well as Bayesian model averaging (BMA) were used to reduce the bias and dispersion existing in ensemble prediction and to provide probabilistic forecast. Prior to applying the prediction methods, reliability of the ensemble forecasts was tested by using a rank histogram and a residualquantile-quantile plot to identify the ensemble forecasts and the corresponding verifications. The ensemble forecasts had a consistent positive bias, indicating over-forecasting, and were under-dispersed. To correct such biases, statistical post-processing methods were applied using fixed and sliding windows. The prediction skills of methods were compared by using the mean absolute error, root mean square error, continuous ranked probability score, and continuous ranked probability skill score. Under the fixed window, BMA exhibited better prediction skill than the other methods in most observation station. Under the sliding window, on the other hand, homogeneous and non-homogeneous regression models with positive regression coefficients exhibited better prediction skill than BMA. In particular, the homogeneous regression model with positive regression coefficients exhibited the best prediction skill. 相似文献
996.
Yoojin Kim Ha-Rim Kim Yong-Sang Choi WonMoo Kim Hye-Sil Kim 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(5):467-477
Statistical seasonal prediction models for the Arctic sea ice concentration (SIC) were developed for the late summer (August-October) when the downward trend is dramatic. The absorbed solar radiation (ASR) at the top of the atmosphere in June has a significant seasonal leading role on the SIC. Based on the lagged ASR-SIC relationship, two simple statistical models were established: the Markovian stochastic and the linear regression models. Crossvalidated hindcasts of SIC from 1979 to 2014 by the two models were compared with each other and observation. The hindcasts showed general agreement between the models as they share a common predictor, ASR in June and the observed SIC was well reproduced, especially over the relatively thin-ice regions (of one- or multi-year sea ice). The robust predictability confirms the functional role of ASR in the prediction of SIC. In particular, the SIC prediction in October was quite promising probably due to the pronounced icealbedo feedback. The temporal correlation coefficients between the predicted SIC and the observed SIC were 0.79 and 0.82 by the Markovian and regression models, respectively. Small differences were observed between the two models; the regression model performed slightly better in August and September in terms of temporal correlation coefficients. Meanwhile, the prediction skills of the Markovian model in October were higher in the north of Chukchi, the East Siberian, and the Laptev Seas. A strong non-linear relationship between ASR in June and SIC in October in these areas would have increased the predictability of the Markovian model. 相似文献
997.
Based on the global aerological dataset and on the method for determination of the boundaries and amount of cloudiness using the profiles of temperature and humidity obtained from the atmospheric radiosounding data [23], the estimates are computed for the parameters of atmospheric temperature- humidity separation into cloud and intercloud layers from the surface to the height of 10 km. The base and top of cloud layers and their total thickness and frequency are selected as layering parameters. The computations are based on the data for the observational period of 1964-1998. To specify the spatiotemporal features of atmospheric layering, long-term geographic distributions of mean values and standard deviations of the mentioned parameters are constructed for January and July, and the amplitude of their variations is determined. 相似文献
998.
Investigated is the periodic component of geoacoustic emission within the frequency band from 2.0 to 6.5 kHz registered by the piezoceramic hydrophone installed near the bottom of Lake Mikizha in the Kamchatka Peninsula. It is revealed that the variation period is 24 hours and the maximum variation is observed in summer, when the average daily air temperature is above 10°C. In that period the close connection is revealed between the series of air temperature and geoacoustic emission. Taking into account the similar results of measurements of the ground surface slope at the observation site, the most probable reason for the diurnal variations of high-frequency geoacoustic emission is the deformation of near-surface sedimentary rocks caused by diurnal variations of temperature. 相似文献
999.
E. Sh. Elizbarashvili M. E. Elizbarashvili N. B. Kutaladze I. Keggenhoff Sh. E. Elizbarashvili B. M. Kikvadze N. M. Gogia 《Russian Meteorology and Hydrology》2016,41(4):261-267
Using observational data from 50 weather stations in Georgia for the period of 1936-2013, the following climate indices of moisture regime are studied: maximum 1-day precipitation, maximum 5-day precipitation, the simple daily intensity index, the number of days with precipitation equal to not less than 10, 20, and 50 mm, number of consecutive wet and dry days. Geoinformation maps of the spatial structure are plotted, and the dynamics of these indices is studied for the period of global warming. Expected changes in the moisture regime in different physiographic regions in Georgia are assessed. 相似文献
1000.
A. D. Kleshchenko V. M. Lebedeva T. A. Goncharova T. A. Naidina N. M. Shklyaeva 《Russian Meteorology and Hydrology》2016,41(4):299-306
The methodological approach is proposed to the estimation of drought-related crop yield loss based on the dynamic statistical model of crop productivity forecasting. The obtained results agree well with the total actual crop yield loss. The approach under consideration is the first stage of creation of operational assessment of expected loss. 相似文献