Data Of Satellite Measurements Research Articles

Reservoir water budget estimation using satellite and ground measurement data

Rising air temperatures, increased rainy runoff, reduced dry season runoff, and severe weather conditions have intensified floods and droughts, significantly affecting the reservoir water supply. The accuracy of reservoir water balance is crucial for meeting water needs. The study compares satellite data and ground measurements to analyze the water budget of Sutami Reservoir in Indonesia. Satellite data collected included precipitation (Tropical Rainfall Measuring Mission-TRMM) and evaporation (Global Land Data Assimilation System-GLDAS). The water balance approach was utilized to analyze the water budget. The suitability tests used were Root Mean Square Error (RMSE), Nash-Sutcliffe Efficiency (NSE), Correlation Coefficient (CC), and Relative Error (RE). The study revealed that the data from TRMM and GLDAS satellites closely resembled ground measurements. The reservoir water balance analysis revealed that satellite data aligns with ground measurements, indicating water shortages in the dry season and excess water in the rainy season. Satellite data is particularly beneficial for watershed management in areas lacking ground measurement equipment, as it can be analyzed for various purposes.

Stratospheric Ozone Content Variations Over the City of Obninsk from Data of Lidar and Satellite Measurements

Stratospheric Ozone Content Variations Over the City of Obninsk from Data of Lidar and Satellite Measurements

Stratospheric Ozone Variations Over Obninsk from Data of Lidar and Satellite Measurements

Analysis of variations of stratospheric ozone content at 13–18, 18–23 and 23–30 km layers is presented from data of lidar and satellite measurements in 2014–2022 over Obninsk city (55.1° N, 36.6° E). Modeling of deviations from seasonal run for separate quarters of year are fulfilled by using of linear regression method. Impact factors under consideration are quasi-biennial oscillation of zonal wind in tropical stratosphere (QBO), Arctic oscillation (AO), El-Nino – Southern oscillation (ENSO), solar activity (SA), volcanic aerosol (VA) and polar stratospheric clouds (PSC). Enhancement of ozone content is observed in eastern QBO phase at 18–30 km layer (I–II quarter) and in western QBO phase at 13–23 km layer (IV quarter). At separate layers it is revealed significant impacts of AO (II–III quarters), SA (I–II quarters) and VA (III–IV). During a year influence of PSC is originally showed in II quarter at 13–18 layer and then in IV quarter at 13–18 layer. Possible physical mechanisms are discussed which are the basis of the correlation relations observed.

Simultaneous Ground and Satellite Measurements of the Polarization Jet at the Yakutsk Station Meridian

The data of simultaneous measurements of the polarization jet from the Yakutsk ground-based vertical radio sounding station and satellite observations of narrow electron density dips or fast westward drifts of the ionospheric plasma from satellites of the Defense Meteorological Satellite Program (DMSP) series. The events are based on ground-based ionospheric measurements and cover the time interval from March 1989 to December 2015, i.e. about 26 years. The simultaneity of observations is ensured by a time period of approximately ±1.5 h from the time of registration of signs of a polarization jet according to the data of a ground-based ionospheric sounding station or by the an orbital period of DMSP satellites around the Earth. Based on data of long-term simultaneous satellite and ground-based measurements (126 events), it was shown and confirmed that the presence of characteristic additional traces of reflections on ionograms indicates the presence of narrow and fast drifts of ionospheric plasma or a polarization jet near the zenith of the observation station. It is also shown that the quasi-instantaneous longitude extent of a polarization jet at subauroral latitudes can in some cases reach 8 h or 120° by longitude.

Interpretation of fluxes of cosmic rays’ nuclei and electrons in the nonclassical diffusion model

We discuss new scenario of the formation of the observed spectra of electrons/positrons and nuclei of ultrahigh-energy cosmic rays in the framework of the nonclassical (superdiffusion) model of particles propagation in a highly inhomogeneous interstellar and intergalactic media. It is shown that the proposed scenario provides a consistent description of the experimental data of precision satellite measurements, ground-based hybrid EAS arrays and Cherenkov telescopes on the spectra of leptons and nuclei, as well as the mass composition of cosmic rays in the range of super-high and ultrahigh energies.

Algorithm for the Reconstruction of the Ground Surface Reflectance in the Visible and Near IR Ranges from MODIS Satellite Data with Allowance for the Influence of Ground Surface Inhomogeneity on the Adjacency Effect and of Multiple Radiation Reflection

An atmospheric correction algorithm is proposed for the reconstruction of the ground surface reflectance from the data of satellite measurements. A distinctive feature of the algorithm is that it takes into account the influence of the ground surface inhomogeneity on the adjacency effect and additional illumination of the ground surface by reflected radiation. These factors are important for the reconstruction of the reflectance of ground surface fragments with sharp reflectance changes and high atmospheric turbidity. The algorithm is based on Monte Carlo programs developed by the authors. To reduce the computing time, we have proposed some original criteria and approaches. To estimate the capabilities of the developed algorithm, its results have been validated by comparing with the results of the MOD09 algorithm for four MODIS bands and measurements for the Portugal surface fragment with coordinates 38.829 N, 8.791 W. Good agreement of the results obtained by the proposed algorithm with the surface measurements and the data obtained by the MOD09 algorithm demonstrates the efficiency of the proposed algorithm in the reconstruction of the ground surface reflectance.

Field of the atmospheric water vapor as a characteristic of heat and dynamic processes at the ocean surface observed by the microwave radiometric means from space

An approach to indication and analysis of heat and dynamic processes at the ocean surface and in the atmosphere with the methods of satellite passive microwave radiometry is considered. It bases on a responsiveness of the oceanic and atmospheric up-going microwave radiation to these processes in the spectral band of its attenuation in the atmosphere water vapor, which seems to be as kind of window of the "radio visibility" from satellites. The effectiveness of that approach is caused by the fact that atmospheric water vapor is an active participant (agent) in its heat interaction with the ocean surface and, at the same time, serves as its reliable quantitative indicator. Measured from satellites, natural microwave radiation of the atmospheric water vapor gives distinct signals of changes occurring in the frontal, storm and cyclonic zones in the ocean; they are manifested in the form of pics or jumps of the brightness temperature. The paper provides various examples of the study of such processes as the ocean-atmosphere heat interaction at the middle latitudes of the North Atlantic, origination and propagation of the tropical hurricanes in the Gulf of Mexico and Caribbean Sea, atmospheric water vapor transport in the tropical Atlantic and its influence on cyclogenesis in the Gulf of Mexico, etc. The data of satellite, ship and buoy measurements are widely used to attain and verify results of our study.

Dynamic of the Earth crust vertical movements during the Holocene

This work is a complex of theoretical studies of the dynamics of local vertical earth's crust movements. The article proposes a method for separating local curves of sea level change into eustatic and tectonic components. The results of calculations of the dynamics of the local Mediterranean coast vertical movements in the Holocene using materials from geological studies are presented. The data of satellite measurements of the current tectonic movement velocities are presented. The calculated values and satellite measurements are compared.

Space–Time Structure of Energetic Electron Precipitations according to the Data of Balloon Observations and Polar Satellite Measurements on February 1–6, 2015

Space–Time Structure of Energetic Electron Precipitations according to the Data of Balloon Observations and Polar Satellite Measurements on February 1–6, 2015

Identification of Acoustic-Gravity Waves According to the Satellite Measurement Data

Identification of Acoustic-Gravity Waves According to the Satellite Measurement Data

Site selection for solar photovoltaic system installation using analytical hierarchy process model in Azerbaijan

The most suitable sites for solar photovoltaic power installations are determined through a comprehensive assessment of the meteorological, economic and environmental criteria of the energy potential areas. The basic criteria for location selection are evaluated using an analytical hierarchy process method based on multi-criteria decision-making technique for large-scale solar photovoltaic projects. The analytical hierarchy process model is also applied to evaluate areas of high solar potential and factors that are primary criteria for determinate the site suitability index modelling. This method considers various conditions, such as production and technological considerations, which aim to maximise the short-term profit from the project and the efficiency of power generation. In the study, a consistency ratio of suitable localities was determined and proper alternatives for the construction of photovoltaic installations were evaluated. In addition to local meteorology and related satellite measurement data, the country’s radiation values also were compared by converting a digital elevation model data using the tool «Area solar radiation» in GIS. As a result of calculating the site suitability index with the ArcGIS weighted overlay tool, it was concluded that 1.17 % (1016.8 km2) of the country are the most suitable sites for the installation of solar PV systems. These areas mainly include Khizi, Gobustan, Hajigabul, Beylagan, Sharur, Babek and Jeyranchol zones. The total number of locations identified accross the country, classified into 3 categories according to their level of suitability, includes 40 sites. Eight of these high suitability sites, all in Nakhchivan Autonomous Republic, contain 11 % (109.2 km2) of the total potential area. The remaining 32 sites, corresponding to areas with medium and low energy potential, cover 28 % (284.6 km2) and 61 % (623 km2), respectively. When these areas are completely covered with PV panels, it will be possible to fully supply the energy demand of the country with solar energy.

Simulation study of radionuclide atmospheric transport after wildland fires in the Chernobyl Exclusion Zone in April 2020

This paper presents model results for the dispersion of radionuclides released into the atmosphere by intense forest fires in the Chernobyl Exclusion Zone in April 2020. The 137Cs activity concentration in the surface air is calculated on a regional scale (in Ukraine) and a local scale (within the Chernobyl Exclusion Zone). The 137Cs activity in the surface air of Kyiv was found to have reached 2–4 mBq m−3 during the period April 4–20. The results presented in this paper are generally consistent with measured data pertaining to radioactive contamination in Kyiv and areas around several nuclear power plants in Ukraine. The total effective dose to the population of Kyiv during the fire period was estimated to be 5.7 nSv from external exposure and the inhalation of 137Cs and 90Sr, rising to 30 nSv by the end of 2020. This is about 0.003% of the annual permissible level of exposure of the population. A committed effective dose of about 16 nSv was estimated for the personnel of the Chernobyl nuclear power plant from the inhalation of 137Cs and 90Sr during the 2020 forest fires. A method for estimating the radionuclide activity emissions during wildland fires in radioactively contaminated areas is proposed. This method is based on satellite measurement data of the fire radiative power, the radionuclide inventory in the fire area, and an emission factor for radioactive particles.

基于CSOP的低轨卫星测控数传资源静态调度模型研究

基于CSOP的低轨卫星测控数传资源静态调度模型研究

Two-frequency acoustic-gravitational waves, simulation of satellite measurements

The theory of acoustic gravity waves (AGW) considers free disturbances of the atmosphere within the framework of a single-frequency approach. In this case, the theory implies the existence of two separate types of waves with different natural frequencies - acoustic and gravitational. In the single-frequency approach, wave fluctuations of density, temperature, and velocity are related to each other through the spectral characteristics of the wave, and these relationships are unchanged. However, satellite observations of AGW parameters cannot always be explained within the framework of a single-frequency approach. This paper presents a two-frequency approach to the study of AGWs using the model of two coupled oscillators. It is shown that the perturbed movements of the elementary volume of the medium occur simultaneously at two natural frequencies. In this case, the connections between the wave fluctuations of the parameters are determined by the initial conditions, which can be arbitrary. Solutions in real functions for an isothermal atmosphere are obtained. The conditions under which single-frequency AGWs are obtained from the general two-frequency solution are investigated. The AGW waveforms measured from the satellite for velocities and displacements in single-frequency and dual-frequency modes are numerically simulated. The results of simulating two-frequency AGWs agree with the data of satellite measurements. Two-frequency AGWs are not always implemented at two different frequencies. It is shown that when the frequencies approach each other, the beat effect occurs and two closely related modes become indistinguishable. At the same wavelength, they have one center frequency and one phase velocity. The main feature of the two-frequency approach to the study of AGW is the expansion of the relationships between the wave parameters of the medium. This makes it possible to achieve satisfactory agreement of the model waveforms with the data of satellite measurements. Thus, the use of a two-frequency AGW treatment opens up new possibilities in the interpretation of experimental data.

Two-Frequency Acoustic-Gravitational Waves and Simulation of Satellite Measurements

The theory of acoustic gravity waves (AGW) considers free disturbances of the atmosphere within the framework of a single-frequency approach. In this case, the theory implies the existence of two separate types of waves with different natural frequencies: acoustic and gravitational. In the single-frequency approach, wave fluctuations of density, temperature, and velocity are related to each other through the spectral characteristics of the wave, and these relationships are unchanged. However, satellite observations of AGW parameters cannot always be explained within the framework of a single-frequency approach. This paper presents a two-frequency approach to studying AGWs using the model of two coupled oscillators. It is shown that the perturbed movements of the elementary volume of the medium occur simultaneously at two natural frequencies. In this case, the connections between the wave fluctuations of the parameters are determined by the initial conditions, which can be arbitrary. Solutions in real functions for an isothermal atmosphere are obtained. The conditions under which single-frequency AGWs are obtained from the general two-frequency solution are investigated. The AGW waveforms measured from the satellite for velocities and displacements in single-frequency and dual-frequency modes are numerically simulated. The results of simulating two-frequency AGWs agree with the data of satellite measurements. Two-frequency AGWs are not always implemented at two different frequencies. It is shown that, when the frequencies approach each other, the beat effect occurs and two closely related modes become indistinguishable. At the same wavelength, they have one center frequency and one phase velocity. The main feature of the two-frequency approach to the study of AGW is the expansion of the relationships between the wave parameters of the medium. This makes it possible to achieve satisfactory agreement of the model waveforms with the data of satellite measurements. Thus, the use of a two-frequency AGW treatment opens up new possibilities in the interpretation of experimental data.

Застосування величини FRP (Fire Radiative Power) для оцінки емісії радіонуклідів в атмосферу внаслідок лісових пожеж у зоні відчуження у квітні 2020 р.

A method is proposed for assessing the activity of radionuclides released into the atmosphere during forest and meadow fires in radioactively contaminated areas, based on using satellite measurement data of the fire radiative power (FRP), as well as data on the radionuclide deposition density in the fire area and the value of the emission factor Cr of the activity of aerosol particles formed during fires. The method was applied for forest fires in the Exclusion Zone in April 2020. The used FRP values were obtained from MOD14 (Terra) / MYD14 (Aqua) for MODIS Collection 6, VIIRS (S-NPP) I Band 375 m and VIIRS (NOAA-20/JPSS-1) I Band 375 m AF products of the Fire Information for Resource Management System (NASA). A comparative analysis of the data of these satellites showed that the spatio-temporal dynamics of the spread of fire areas in the Exclusion Zone is better reproduced by the results of VIIRS radiometer measurements. Using the satellite data, calculations of fire radiative energy (FRE) were made taking into account the daily course of aerosol emission intensity. Preliminary estimates of the Cr value were obtained as 9.5 ⋅ 10-4 m2 /MJ for 137Cs. These results should be considered as preliminary estimates now. In the general case, the emission factor for radioactive aerosols Cr should depend on the geographical region, type of vegetation and land use in the fire area. Its value may be clarified both by the results of retrospective studies of forest fires in recent years in radioactively contaminated areas, and by specially conducted experiments (in particular, measurements of the specific activity of aerosol particles formed during fires). The proposed method enables operational assessments and prediction of the consequences of forest fires, including model assessments of the atmospheric transport of radioactive aerosols and assessments of exposure doses to the personnel of the Exclusion Zone and the population outside it using online computer-based decision support systems for protecting people from the effects of radioactive contamination of the environment.

Calibration of atmospheric density model based on Gaussian Processes

Neutral mass density is presently the predominant uncertain term among all the factors affecting the atmospheric drag, which is the dominant perturbation force for space objects at low altitude. The current best density estimation performance is often achieved by empirical models that can be limited by their assumed, parametric formulations of regression. This paper presents a density estimation framework that integrates information from empirical models, environment conditions, and satellite measurement data. Different from existing frameworks, the new integration mechanism is based on Gaussian Processes (GPs) which are nonlinear, non-parametric regression methods. The method can estimate both current and future densities. Furthermore, it will provide uncertainty quantifications in its estimates through GPs' underlying Bayesian inference. Simulations are designed to test the hypothesis that the new framework is valuable to improve the nowcast performance of the empirical models, and to predict future density. Empirical models including NRLMSISE-00 and JB2008 and accelerometer-inferred densities from satellite CHAMP are used for the study. The new method is shown to achieve better Pearson correlation coefficient (R), root mean squared error (RMSE), and mean ratio from the empirical models when the density estimation is tested on both the missing data and future densities, which are, respectively, within and following the GP's training period. Together with providing quality uncertainty estimations, the proposed framework has the great potential to reduce the estimation errors from the empirical model and provide an effective means to estimate density for a satellite.

Carbon Monoxide Variations in the Antarctic Atmosphere from Ground-Based and Satellite Measurement Data

The results of systematic (2003–2017) measurements of the total content and height-averaged relative volume concentration of CO at st. Novolazarevskaya with a spectrometer with a resolution of 0.2 cm–1 are presented. The inverse problem of determining the total content of CO as well as interfering gases (H2O and N2O) was solved using the SFIT4 software package. A data analysis indicated that during the measurements the average total CO content at st. Novolazarevskaya was (8 ± 2) 1017 molecules/cm2 and the height-averaged volume concentration was (37 ± 8) ppb. The resulting data were compared with variations in the total CO content at st. Arrival-Heights, MOPITT satellite data, and CO surface concentrations at st. Syowa. The maximum and minimum values of CO were observed in September and January–February, respectively. For all the data series considered, the trends are insignificant; in this case, an increased CO content was observed in 2010, and an increasing trend of the minimum values of CO was observed in recent years (2014–2017). Both stations (Novolazarevskaya and Arrival-Heights) are characterized by an excess of satellite data over ground-based measurement data (19% and 14%, respectively); here, a seasonal dependence of the deviation was observed with minimal deviations in December–January. Data of surface measurements of the total content at st. Novolazarevskaya and Arrival-Heights are rather well consistent, and the average deviation since 2010 was 2.4%. The average concentration of CO at st. Syowa (51 ppb) is higher than the height-averaged concentration at st. Novolazarevskaya. According to spectral, wavelet, and composite analyzes, all data series considered include oscillations in the range of 6–45 months with almost identical periods and phase relationships.

The Four Patterns of the East Branch of the Kuroshio Bifurcation in the Luzon Strait

Based on the self-organizing map (SOM) method, a suite of satellite measurement data, and Hybrid Coordinate Ocean Model (HYCOM) reanalysis data, the east branch of the Kuroshio bifurcation is found to have four coherent patterns associated with mesoscale eddies in the Pacific Ocean: anomalous southward, anomalous eastward, anomalous northward, and anomalous westward. The robust clockwise cycle of the four patterns causes significant intraseasonal variation of 62.2 days for the east branch. Furthermore, the study shows that the four patterns of the east branch of the Kuroshio bifurcation can influence the horizontal and vertical distribution of local sea temperature.

Cloud Cells by Data of Satellite Measurements and Convective Energy Balance on Invasion of Cold Air into the Atmosphere over the Black Sea

This paper considers a typical case of winter cold air invasion into the Black Sea region in January 2010. Using the WRF numerical model, the intensive convection over the sea on January 25 has been reproduced and the simulation results have been verified using satellite data on cloudiness, cloud top temperature, and specific humidity. It has been shown that, according to both the modeling results and the satellite data, mixed convection over the sea occurred but with the prevalence of cells playing the main part in the mixing in the atmospheric boundary layer (ABL). The cloud top height has been determined both by satellite data and by simulation results; it has been shown that the model reproduces the observed increase in the cloud top height over the sea with the distance from the coast. Spectral analysis of the vertical convective moisture flux fields has shown that the model correctly reproduced the horizontal size of cloud structures near the shore. It was found from the modeling results and satellite pictures that the horizontal size of convective cells over the sea increased downwind. The main components of the convective kinetic energy balance in the atmospheric boundary layer have been considered: energy generation due to pressure pulsations and work of the buoyancy force, as well as the decrease in energy due to turbulent diffusion and convective advection. It has been shown how these quantities varied with height and with the distance from the shore.