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931.
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
932.
E. V. Kharyutkina S. V. Loginov Yu. V. Martynova 《Russian Meteorology and Hydrology》2016,41(6):435-438
The estimates of spatiotemporal variability of climatic parameters in West Siberia are obtained over the period of 1976-2014. It is revealed that this variability is affected by the parameters of atmospheric circulation such as wind speed components, relative vorticity, and large-scale circulation indices. It is found that in winter the warming changed into the cooling that is particularly associated with the change in atmospheric circulation patterns described by the SCAND index. 相似文献
933.
A. M. Zvyagintsev N. S. Ivanova I. N. Kuznetsova V. A. Lapchenko N. V. Tereb 《Russian Meteorology and Hydrology》2016,41(9):662-664
The review is compiled on the basis of the operation of the total ozone (TO) monitoring system in the CIS and Baltic countries that functions in the operational regime at the Central Aerological Observatory. The monitoring system uses the data from the national network equipped with M-124 filter ozonometers under methodological supervision of the Main Geophysical Observatory. The quality of the functioning of the entire system is under the operational control based on the observations obtained from the OMI satellite equipment (NASA, the United States). The basic TO observation data are generalized for each month of the second quarter of 2016 and for the quarter as a whole. The data of routine observations of surface ozone content carried out in the Moscow region and Crimea are also presented. 相似文献
934.
E. V. Gorbarenko 《Russian Meteorology and Hydrology》2016,41(11-12):789-797
Variations in radiation fluxes and the factors that define them and their redistribution in the atmosphere are analyzed using the data of long-term ground-based measurements at the Meteorological Observatory of Lomonosov Moscow State University. It is demonstrated that since the middle of the 1990s trends in many atmospheric radiation parameters have changed as compared to the trends observed in the previous years. For some parameters the trends are significant, are kept for a long period of time, and. hence, can be considered as climate changes. The potential effects of these changes on the regional warming are assessed. 相似文献
935.
D. A. Yarovaya 《Russian Meteorology and Hydrology》2016,41(8):535-543
The statistical study of intense mesoscale cyclones formed in the Black Sea region in 1979-2013 is carried out using the surface wind data of the RegCM climate model. Such cyclone parameters as intensity, lifetime, area, height, and trajectories over the sea as well as the place and time of origin are considered. The distribution of mesocyclones by months and times of day is considered. The obtained results are compared with the results of a statistical study on the Black Sea mesocyclones based on the PRECIS climate model. Possible causes for differences in data on the intensity and number of mesocyclones simulated by RegCM and PRECIS models are considered. 相似文献
936.
937.
938.
Kiran Chand Thumaty Rakesh Fararoda Suresh Middinti Rajashekar Gopalakrishnan C. S. Jha V. K. Dadhwal 《Journal of the Indian Society of Remote Sensing》2016,44(1):31-39
Reliable and accurate estimates of tropical forest above ground biomass (AGB) are important to reduce uncertainties in carbon budgeting. In the present study we estimated AGB of central Indian deciduous forests of Madhya Pradesh (M.P.) state, India, using Advanced Land Observing Satellite – Phased Array type L-band Synthetic Aperture Radar (ALOS-PALSAR) L-band data of year 2010 in conjunction with field based AGB estimates using empirical models. Digital numbers of gridded 1?×?1° dual polarization (HH & HV) PALSAR mosaics for the study area were converted to normalized radar cross section (sigma naught - σ0). A total of 415 sampling plots (0.1 ha) data collected over the study area during 2009–10 was used in the present study. Plot-level AGB estimates using volume equations representative to the study area were computed using field inventory data. The plot-level AGB estimates were empirically modeled with the PALSAR backscatter information in HH, HV and their ratios from different forest types of the study area. The HV backscatter information showed better relation with field based AGB estimates with a coefficient of determination (R2) of 0.509 which was used to estimate spatial AGB of the study area. Results suggested a total AGB of 367.4 Mt for forests of M.P. state. Further, validation of the model was carried out using observed vs. predicted AGB estimates, which suggested a root mean square error (RMSE) of ±19.32 t/ha. The model reported robust and defensible relation for observed vs. predicted AGB values of the study area. 相似文献
939.
为了提供可靠的伪距随机模型,基于3个线性无关的北斗三频伪距/载波无几何无电离层(GIF)组合,研究了一种利用单站数据估计北斗三频伪距相关随机模型算法。该算法首先利用低阶多项式对GIF组合进行拟合,以尽可能消除非伪距噪声以外的其他常数和误差,然后利用多元线性回归分析实现对3个线性无关的GIF组合随机噪声同时建模,最后再由线性组合关系变换得到原始北斗三频伪距相关随机模型。经北斗三频实测数据验证结果表明,该算法可实现北斗非差三频伪距相关随机模型的单站解算,有利于为导航定位以及完好性监测提供精准随机模型。 相似文献
940.
Kathleen M. Baker Andrew C. Johnson Caitlin N. Callahan Heather L. Petcovic 《制图学和地理信息科学》2016,43(2):176-187
Topographic maps and aerial photographs are particularly useful when geoscientists are faced with fieldwork tasks such as selecting paths for observation, establishing sampling schemes, or defining field regions. These types of images are crucial in bedrock geologic mapping, a cognitively complex field-based problem-solving task. Geologic mapping requires the geologist to correctly identify rock types and three-dimensional bedrock structures from often partial or poor-quality outcrop data while navigating through unfamiliar terrain. This paper compares the walked routes of novice to expert geologists working in the field (n = 66) with the results of a route planning and navigation survey of a similar population of geologists (n = 77). Results show clearly that those geologists with previous mapping experience make quick and decisive determinations about field areas from available imagery and maps, regardless of whether they are or not physically present in the field area. Recognition of geologic features enabled experts to form and verbalize a specific plan for travel through a landscape based on those features. Novices were less likely to develop specific travel route plans and were less likely to identify critical landscape cues from aerial photographs. 相似文献