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1.
Lithology and Mineral Resources - Sedimentological features of the Upper Cambrian–Middle Ordovician rocks exposed in eastern Taimyr in the Faddey Gulf area are discussed. The studied sections...  相似文献   
2.
Theoretical and Applied Climatology - Rainfall components likely differ in the magnitude and direction of their long-term changes for any given location, and some rainfall components may carry a...  相似文献   
3.
Geomagnetism and Aeronomy - An empirical model of the equatorial anomaly in the critical frequency foF2 of the ionospheric F2 layer is constructed. The model is based on Interkosmos-19 satellite...  相似文献   
4.
Theoretical and Applied Climatology - El Niño events lead to worldwide changes in the inter-annual variability of precipitation, and more in particular to South America droughts. In the year...  相似文献   
5.
Prajapati  V. K.  Khanna  M.  Singh  M.  Kaur  R.  Sahoo  R. N.  Singh  D. K. 《Theoretical and Applied Climatology》2022,149(1-2):207-220
Theoretical and Applied Climatology - This paper presents a composite approach for drought characterization and monitoring using in situ and remote sensing-based drought indicators. The study was...  相似文献   
6.
Geomagnetism and Aeronomy - Diurnal variations in the statistical characteristics of the day-to-day variability in the electron number density NmF2 of the ionospheric F2 layer maximum is studied...  相似文献   
7.
Groundwater level (GWL) varies periodically or non-periodically with various factors including precipitation, river stage (RS) change, sea level, and dewatering activities. In this study, the effect of influence components on the prediction of GWL using an artificial neural network (ANN) was investigated. Six regions with different hydrologic and geologic conditions were collected and adopted in the investigation using various input combinations. In urban areas with a high surface paved ratio, GWL was mainly affected by RS. In rural areas, the permeability of ground showed a significant impact on GWL. For such cases, the moving average (MA) was a suitable component as it could reflect both time lag and the effect of preceding precipitation. It was shown that site-specific influence component should be firstly identified and introduced into input for more enhanced and reliable prediction of GWL using ANN. The effect of learning data length (LDL) was less significant. In urban and rural areas, the introduction of RS and MA into ANN input significantly improved the prediction performance, respectively, which was consistent with the correlation analysis of GWL influence components.  相似文献   
8.
Geomagnetism and Aeronomy - Based on an analysis of data from the midlatitude ionospheric stations, it is found that the P = 0.5(F1 + F81) index is an optimal solar-activity index for the daily...  相似文献   
9.
Gorelits  O. V.  Kryjov  V. N.  Rakcheeva  E. A.  Ermakova  G. S. 《Water Resources》2022,49(5):836-844
Water Resources - Based on 1965–2020 series we have shown relationships between the features of the water runoff of the spring flood in mouths of large rivers of North-Eastern Europe and the...  相似文献   
10.
Marine ferromanganese nodules and crusts containing Mn, Cu, Ni and Co in the most promising resource-grade concentrations and quantities, together with Fe and Zn (all elements of biogeochemical importance) are found far from land on the deep seafloor of the Pacific Ocean. The biogeochemical, chemical and physical mechanisms contributing to their formation, distribution, abundance and – for these six elements – variability in their concentrations in these deposits, are the main focus of the present review. The mechanisms addressed include biological productivity, sedimentation types and rates, bottom water characteristics, the Calcium Carbonate Compensation Depth, the depth and intensity of the oxygen minimum zone, and biogeochemical characteristics of the six focal elements. Particular attention is given to comparisons between the deposits found in the north and the south Pacific, in order to present an overarching view of our current understanding of the mechanisms that apply to both nodules and crusts in both oceanic hemispheres, including examination of the possible existence of a marine ferromanganese oxide continuum. The renewed interest in the commercial exploitation of these deposits has stimulated a welcome increase in scientific research that is essential to informing the public discourse on seabed mining. We briefly reflect on the work addressed in this review in that context.  相似文献   
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