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981.
Presented are the explanations of reasons for the anomalous heat in summer of 2010 in the central area of the European part of Russia. It is demonstrated that this event occurred due to the beating of the solar annual (365 days) and lunar annual (355 days) fluctuations of air temperature. To substantiate this conclusion, the data are given on the synchronization of changes in atmospheric processes with the tidal variations of the Earth??s rotation velocity and on the nature of lunar cycles. Illustrated are the evidences of their existence in air temperature fluctuations. Revealed is the sequence of anomalously hot summer seasons in 1901, 1936 (1938), 1972, and 2010 corroborating the existence of the 35-year period of air temperature beats. Proposed is a mechanism of the impact of luni-solar tides on the air temperature based on the interaction between the gravitational luni-solar tides and the radiation conditions in the atmosphere (caused by the cloudiness amount variations).  相似文献   
982.
Presented are the estimates of precipitation amount and evaporation for the Black Sea basin based on the data of numerical regional reanalysis. The spatial distribution of considered variables is compared with the results obtained before using the method of extrapolation of measurements at the coastal meteorological stations. The computed water balance components of the Black Sea compared with the available literature data are used for obtaining the estimate of the mean water discharge in the Bosphorus.  相似文献   
983.
The method is proposed to determine the main fluxes characterizing the surface stratified layer of plants’ habitat using the Monin-Obukhov length scale. The gradient measurements of the profiles of wind flow speed, relative humidity, and air temperature are carried out. The experimental data are obtained using the mobile automated system. The wavelet analysis of time series is carried out. The nonlinear equation system is numerically solved to determine the heat, moisture, and momentum fluxes which can be used for the optimum control of the plant moisture supply in the agricultural field.  相似文献   
984.
Sampling efforts are constrained by limited availability of resources. Therefore, methods to reduce the number of samples, while still achieving reasonable accuracy are needed. Land-surface segmentation (LSS) has proven a powerful technique to partition digital elevation models (DEMs) and their derivatives into relatively homogeneous areas, which can be further employed as support in soil sampling. Though topography is one of the main soil forming factors, a robust assessment of the potential of this technique to digital soil mapping (DSM) is still missing. In this study, we aimed at evaluating the potential of LSS in stratifying a landscape into relatively homogeneous areas, which can be used as strata for guiding the selection of sampling points in DSM. The experiments were carried out in two study areas where soil samples were available. Land-surface derivatives were derived from DEMs and segmented with a tool based on the multiresolution segmentation algorithm, into objects considered as homogeneous soil-landscape divisions. Thus, one sample was randomly selected within each segment from the existing sample data, based on which predictions of soil classes/sub-orders and properties, i.e. soil texture and A-horizon thickness, were made. Results were compared with predictions based on simple random sampling (SRS) and conditioned Latin hypercube (cLHS). The segmentation-based sampling (SBS) scheme performed better than SRS and cLHS schemes in predicting the A-horizon thickness, soil texture fractions and soil classes, showing a high potential of LSS in stratifying a landscape for the purposes of DSM. The novelty of this study is in the way strata are constructed, rather than in the sampling design itself. Further research is needed to demonstrate the value of a SBS design for practical use. The analyses presented here further highlight the importance of considering locally adaptive techniques in optimization of sampling schemes and predictions of soil properties.  相似文献   
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987.
Pollen collected from snow samples on the Quelccaya Ice Cap in 2000 and 2001 reveals significant interannual variability in pollen assemblage, concentration, and provenance. Samples from 2000, a La Niña year, contain high pollen concentrations and resemble samples from the Andean forests (Yungas) to the east. Samples from 2001, an El Niño year, contain fewer pollen and resemble those from the Altiplano. We suggest that varying wind patterns under different El Niño/Southern Oscillation (ENSO) conditions may affect the processes of pollen transport over the Altiplano and on the ice cap, although confounding variables such as flowering phenology and sublimation should also be considered  相似文献   
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