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1.
The influence of internal gravity waves on the spatial coherence and temporal variability of the atmospheric pressure, wind velocity, and gas constituents near Moscow and Beijing is studied in the mesoscale range of periods: from a few tens of seconds to several hours. The results of simultaneous measurements of variations in the atmospheric pressure (using a network of spaced microbarographs), wind velocity at different heights of the atmospheric boundary layer, and gas constituents are given for each city. The wave structures are filtered using a coherence analysis of the atmospheric pressure variations at different measurement sites. The dominant periods and the coherences, phase speeds, and horizontal scales of variations corresponding to these periods are estimated. The general mechanism of the influence of wave structures on meteorological fields and gas constituents is discussed, which is independent of the measurement site and the specificity of meteorological conditions.  相似文献   

2.
A discussion of the influence of sea roughness and spatial atmospheric inhomogeneities on the precision of satellite microwave radiometric measurements of the atmospheric parameters is presented. The two-scale model for microwave radiation of the ruffled sea surface without foam and spray is confirmed by experimental measurements. Investigations of the brightness temperature fluctuations of the clear and cloudy atmosphere are made using aircraft experimental measurements at the wavelengths 0.8 and 1.35 cm. Calculations of the radiation averaged over a satellite antenna footprint are carried out on the basis of these results and of well-known results of optical and infrared measurements. It is shown that sea roughness and the nonuniformity of clouds may result in errors in the integrated atmosphere water vapor and cloud liquid water content determination by satellite two-wavelength (0.8 and 1.35 cm) radiometric measurements up to 30 and 70 percent, respectively.  相似文献   

3.
A computational method for diagnosing three-dimensional atmospheric fronts from temperature, wind, and geopotential fields on a three-dimensional regular grid is proposed. The criterion, which serves for the diagnosis of atmospheric fronts, is discussed. The weights of the input information about the mentioned fields are optimized based on the maximal difference between the correlation functions for (a) pairs of particles separated by the front and (b) pairs from one synoptic mass. These weights were different for different baric levels. The correlation functions and the optimization of weights were estimated on the basis of the archive of fields of the NCEP objective analysis on the half-degree latitude-longitude grid and data from aerological observations. The results of numerical experiments on the construction of atmospheric fronts are presented. Applying the described method to fields predicted for a term of up to 36 h showed that errors in the prognostic models introduce a relatively weak distortion into the geometry of atmospheric fronts.  相似文献   

4.
Results of simultaneous measurements of the direct solar radiation flux and of the degree of polarization of visible light scattered at the zenith at a different albedo of the underlying surface covered with snow after heavy snowfalls or having no snow cover are analyzed. The possibility of monitoring air turbidity on the basis of polarimetric measurements is confirmed. A procedure of remote detection of the effect of solar light polarization on atmospheric aerosol is proposed and implemented.  相似文献   

5.
The possibility of remotely monitoring the total atmospheric ozone content (TAOC) using data from the multichannel geostationary scanning instrument (MGSI) aboard the Elektro-L no. 1 Russian meteorological satellite is explored. In addition to the MGSI measurements in three channels (8.2–9.2, 9.2–10.2, and 10.2–11.2 μm), data on the vertical temperature distributions in the ozone layer and the temperature and pressure at the underlying terrain level (satellite sensing results or forecast data) are used as additional predictors in the process of TAOC estimation. The TAOC estimates are constructed with the use of a regularized regression algorithm (ridge regression). The learning and check samples are formed using independent TAOC estimates based on the data gathered by the OMI instrument aboard the EOS Aura satellite. Numerical experiments in processing the actual MGSI data gathered over certain periods within the interval from November 2011 to August 2012 reveal the possibility of arranging regular monitoring of the TAOC fields with high spatial and temporal resolutions and an acceptable precision: the absolute value of relative mean deviations and the relative root-mean-square deviations of the estimates based on the MGSI data from the estimates based on the OMI data lie within intervals of 1–2% and 5–7%, respectively, depending on the underlying terrain type.  相似文献   

6.
A method is proposed to study the transport of a passive additive in the atmospheric surface layer with the use of the atmospheric transfer function. This method makes it possible to estimate the spatial distribution of the concentration of a passive additive in the atmospheric surface layer from the additive’s surface source without experimentally determining the vertical profile of the transport coefficient or without resorting to various hypotheses for the character of its behavior. The transfer function, which contains the information on the wind-field structure, can be obtained from simple one-point measurements of surface-and air-temperature fluctuations and from subsequent spectral processing of the data. The effects of the wind-velocity profile and turbulence on the spatial distribution of additive concentration are assessed. This method allows one to simplify experiments during development and verification of the models of atmospheric diffusion. This method may also be useful in emergency situations to predict the propagation of hazardous additives.  相似文献   

7.
A method for determining the total ozone (TO) with high spatial (3×3 km2) and temporal (15 min) resolutions by using measurements of the Earth’s outgoing thermal radiation from Meteosat geostationary satellites is proposed. The method is based on measurements with a SEVIRI instrument (eight IR channels) and involves additional information on the three-dimensional field of the atmospheric temperature and on the surface temperature obtained from polar satellites (AIRS instrument). The inverse problem of TO determination is solved by the method of neural networks. TO measurements with the AIRS instrument are also used for training the neural networks. Ground-based TO measurements at the international ozonometric network are used for controlling the quality of AIRS data and detecting the errors of the proposed method of TO determination from SEVIRI data. The mean and rms differences between TO values obtained with the use of the proposed method and from the results of measurements at the international ozonometric network are shown to be 1.5 and 6.5%, respectively. Examples of TO distributions reconstructed with high spatial and temporal resolutions are presented. These examples show that the elaborated method for solving various scientific and applied problems and, in particular, for investigating stratospheric dynamics is promising.  相似文献   

8.
The Black Sea dynamics for two decades (1993–2012) is analyzed. The study is carried out in numerical simulation with the use of a circulation model and assimilation of satellite measurements of free surface elevations and sea-surface temperatures (SSTs). The Black Sea circulation model has a spatial resolution of 4.8 km and 35 vertical levels, which thicken toward the surface. Arrays of ERA-Interim data are used for simulating the atmospheric forcing. A set of 3D arrays of the Black Sea hydrophysical fields is calculated on a regular grid with a time resolution of 24 h. The results are analyzed and compared with available contact measurements of temperature and salinity. This comparison shows a quite good quality of the resulted hydrophysical fields of the Black Sea.  相似文献   

9.
Long-term, continuous, and real-time ocean monitoring has been undertaken in order to evaluate various oceanographic phenomena and processes in the East/Japan Sea. Recent technical advances combined with our concerted efforts have allowed us to establish a real-time monitoring system and to accumulate considerable knowledge on what has been taking place in water properties, current systems, and circulation in the East Sea. We have obtained information on volume transport across the Korea Strait through cable voltage measurements and continuous temperature and salinity profile data from ARGO floats placed throughout entire East Sea since 1997. These ARGO float data have been utilized to estimate deep current, inertial kinetic energy, and changes in water mass, especially in the northern East Sea. We have also developed the East Sea Real-time Ocean Buoy (ESROB) in coastal regions and made continual improvements till it has evolved into the most up-to-date and effective monitoring system as a result of remarkable technical progress in data communication systems. Atmospheric and oceanic measurements by ESROB have contributed to the recognition of coastal wind variability, current fluctuations, and internal waves near and off the eastern coast of Korea. Long-term current meter moorings have been in operation since 1996 between Ulleungdo and Dokdo to monitor the interbasin deep water exchanges between the Japanese and Ulleung Basins. In addition, remotely sensed satellite data could facilitate the investigation of atmospheric and oceanic surface conditions such as sea surface temperature (SST), sea surface height, near-surface winds, oceanic color, surface roughness, and so on. These satellite data revealed surface frontal structures with a fairly good spatial resolution, seasonal cycle of SST, atmospheric wind forcing, geostrophic current anomalies, and biogeochemical processes associated with physical forcing and processes. Since the East Sea has been recognized as a natural laboratory for global oceanic changes and a clue to abrupt climate change, we aim at constructing a 4-D continuous real-time monitoring system, over a decade at least, using the most advanced techniques to understand a variety of oceanic processes in the East Sea.  相似文献   

10.
Seasonal fields of tangenital wind stress over the Black Sea   总被引：1，自引：0，他引：1  
Tangential wind stress fields with a 40×60 spatial step are calculated from the data on atmospheric pressure distribution over the Black Sea over a decade. Their space-time variability is studied. It is shown that maximum values of the tangential wind stress in all seasons are located in the areas southwest of the Crimea and south of the Taman Peninsula. The tangenital wind stress retrieved from wind measurements is compared with the one determined from the atmospheric pressure data.Translated by V. Puchkin.  相似文献   

11.
The long-term evolution of the Black Sea dynamics (1980–2020) is reconstructed by numerical simulation. The model of the Black Sea circulation has 4.8 km horizontal spatial resolution and 40 levels in z-coordinates. The mixing processes in the upper layer are parameterized by Mellor-Yamada turbulent model. For the sea surface boundary conditions, atmospheric forcing functions were used, provided for the Black Sea region by the Euro mediterranean Center on Climate Change (CMCC) from the COSMO-CLM regional climate model. These data have a spatial resolution of 14 km and a daily temporal resolution. To evaluate the quality of the hydrodynamic fields derived from the simulation, they were compared with in-situ hydrological measurements and similar results from physical reanalysis of the Black Sea.  相似文献   

12.
The climatic trends and basic features of seasonal variations in and anomalies of the concentration of methane in the atmospheric surface layer are considered on the basis of the current notion of the processes that form the global field of methane in the Earth’s atmosphere. Measurement data on the surface concentration of methane, which were obtained in Moscow and at a number of observation stations in Europe and Siberia in the fall-winter period of the first decade of the 21st century, have been analyzed. It is shown that, in the anomalously warm winter months of 2006/2007, the concentration of methane in the atmosphere over Moscow was higher than in the previous and following years. The excess concentration of methane amounted to 10% in March 2007, which is higher than the mean range of seasonal variations in the monthly mean concentration of surface methane. A comparison between the data obtained in Moscow and the data obtained at three stations of the NOAA global monitoring network and at three Russian Hydrometeorological Research Center stations shows the high spatial variability of the methane concentration in the atmosphere over northern Eurasia. The complex and multifactor processes that determine the content of methane in the atmospheric surface layer result in noticeable spatial and interannual deviations from the mean seasonal cycle of its concentration, which can manifest themselves on both regional and global scales. It is possible that the resumed increase in the content of methane in the Earth’s atmosphere recorded in 2007 (after its relative stabilization in the early 2000s) at the global monitoring network was also caused, to some extent, by the anomalously warm winter of 2006–2007 in northern Europe and western Siberia.  相似文献   

13.
The complexity of the laws of dynamics governing 3-D atmospheric flows associated with incomplete and noisy observations make the recovery of atmospheric dynamics from satellite image sequences very difficult. In this paper, we address the challenging problem of estimating physical sound and time-consistent horizontal motion fields at various atmospheric depths for a whole image sequence. Based on a vertical decomposition of the atmosphere, we propose a dynamically consistent atmospheric motion estimator relying on a multilayer dynamic model. This estimator is based on a weak constraint variational data assimilation scheme and is applied on noisy and incomplete pressure difference observations derived from satellite images. The dynamic model is a simplified vorticity-divergence form of a multilayer shallow-water model. Average horizontal motion fields are estimated for each layer. The performance of the proposed technique is assessed using synthetic examples and using real world meteorological satellite image sequences. In particular, it is shown that the estimator enables exploiting fine spatio-temporal image structures and succeeds in characterizing motion at small spatial scales.  相似文献   

14.
Results of spectroscopic measurements of the carbon dioxide total column amount near St. Petersburg during forest fires in the period from August to September 2002 are analyzed. The HYSPLIT model is used to calculate air-mass trajectories and CO distribution on a mesoscale in this period. The HYSPLIT model simulations and measurements of carbon dioxide total column amount yield an estimate of the specific intensity of CO emission in a Pskov forest fire on August 28–September 8, 2002, equal to 0.17–0.26 kg m2. This estimate can be used for an estimation of the integral CO emission from fires in northwestern Russian forests and for model simulations of atmospheric CO concentration fields. The estimate of the CO emission from forest fires that is obtained from ground-based measurements can also be made on the basis of satellite measurements if they contain information on CO in the lower tropospheric layers (0 to 2 km).  相似文献   

15.
Both space and time variations in the 222Rn concentration in the atmospheric surface layer over continental Russia were analyzed on the basis of data obtained in the Transcontinental Observations into the Chemistry of the Atmosphere (TROICA) experiments. The measurements were taken from a mobile laboratory which was part of a passenger train moving along the Trans-Siberian Railway from Moscow to Vladivostok. The factors that affect the spatial distribution of both daily and seasonal variations in the concentrations of 222Rn in the surface air were determined: atmospheric vertical stability, geological features of the area under study, and atmospheric precipitation. The influence of temperature inversions on the accumulation of 222Rn in the atmospheric surface layer was analyzed. The fluxes of 222Rn from the soil into the atmosphere were estimated for different regions of Russia.  相似文献   

16.
The variability of the fields of the total ozone content (TOC) and UV erythemal irradiance in the tropical region (30°S–30°N) is studied. The fields of monthly means of the TOC and erythemal irradiance that are based on the TOMS 8 and SBUV 8 satellite observations over the period from 1979 through 2003, with preliminarily eliminated the linear trend and the seasonal cycle, were used as the initial data. The application of the method of empirical orthogonal functions (EOFs) to analysis of initial series made it possible to identify the characteristic spatial and temporal patterns in the fields of TOC and UV-irradiance anomalies that are closely related to solar activity and elements of the atmospheric general circulation, such as the quasi-biennial oscillation and El Niño (La Niña) phenomena. Quantitative estimates and analysis of the fields of TOC and UV-irradiance variations are presented in the study. The revealed spatial, temporal, and phase relations of the fields of ozone variations to some geo-and heliophysical factors are used in the regression model proposed for estimating monthly means of TOC in the tropics and based on the EOF decomposition.  相似文献   

17.
The principal statistical regularities typical of the behaviors of the CH4, CO, and CO2 concentrations in the atmospheric surface layer over the continental Russian territory are revealed from the measurements performed in 1997–2004 along the Trans-Siberian Railroad from Moscow to Khabarovsk with a mobile laboratory. The data obtained under the conditions of the atmosphere free of anthropogenic pollutants are analyzed. For near-background conditions, the typical continental methane, carbon monoxide, and carbon dioxide concentrations and characteristic features of their large-scale spatial distributions and daily variations, including those caused by surface inversions, are determined. Variations in the concentrations of these trace gases over industrial regions are analyzed. Our results are compared to the data obtained at background stations of the world network of atmospheric monitoring and to the data of a numerical simulation.  相似文献   

18.
Izvestiya, Atmospheric and Oceanic Physics - The results of 5-year (2013–2017) measurements of organic (OC) and elemental (EC) carbon aerosol fractions observed at the atmospheric monitoring...  相似文献   

19.
The influence of the Caucasus relief on temporal and spatial variations in meteorological fields is investigated through the numerical integration of nonadiabatic, nonstationary, and nonlinear equations of atmospheric hydrothermodynamics. A dimensionless vertical coordinate is used. In numerical experiments, this coordinate makes it possible to approximate a real relief at a high accuracy and to take into account specific features of a complex orography of the region. The cases of flowing around the relief by large-scale westerly, easterly, northerly, and southerly background winds are modeled. The relief in the lower troposphere is shown to considerably change the spatial structures of large-scale fields of meteorological elements and to form the mesoscale structures of wind, temperature, pressure, and cloudiness that are characteristic of the Caucasus.  相似文献   

20.
Bulk deposition samples were collected during a summer (1997) and a winter (1998) measurement campaign at four coastal stations along the southern Baltic Sea coast and on the Island of Gotland. The data were used to construct Pb and Cd deposition fields over the Baltic Sea. A weak gradient with decreasing deposition rates from the southwest towards the east and north was obtained for Pb. In the case of Cd, the spatial distribution pattern was characterized by an extreme deposition maximum at the Polish station on the Hel Peninsula. The total atmospheric input of Pb and Cd into the Baltic Sea was 550 and 33 t/year, respectively, and exceeds the riverine input by approximately about 50%. Previous measurement-based estimates were higher by a factor 2–3 and indicate a decrease of the atmospheric deposition during the past 10–15 years. The comparison with modelled deposition data yielded partly large differences and was impaired by the fact that 1990 emission inventories were used whereas our measurements were performed in 1997/1998.Relating our deposition estimate and the Pb/Cd input by rivers to the mean concentrations in Baltic Sea water, residence times of 0.29 and 3.6 years were obtained for Pb and Cd, respectively.  相似文献   

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