Radar Picture Research Articles

Heavy rainfall and thunderstorms in south interior Karnataka: a case study on august 31, 2023

Study aims to conduct a synoptic and thermodynamic analysis of significant rainfall events that happened during the break monsoon season. During the investigation of meteorological events, it was observed that the monsoon trough at mean sea level passed along the foothills of the Himalaya. On August 31, 2023, there was a cyclonic circulation observed in the northeast Bay of Bengal as well as adjacent areas, reaching an altitude of 5.8 km above mean sea level (AMSL). This circulation tilted southwestward with height. During the period of August 31-September 2, 2023, there was a cyclonic circulation persistent that occurred inside a particular geographical area. This phenomenon extended up to a height of 4.5 km AMSL and exhibited a south-westward tilt as the altitude increased. On August 31, 2023, the Convective Available Potential Energy (CAPE) was measured to be 2153 J/kg, whereas the Convective Inhibition Energy (CINE) was recorded as 0 J/kg. INSAT-3D satellite image showed a cloud top temperature of – 40 °C to – 60 °C. The Doppler Weather Radar (DWR) pictures also showed convective clouds to support this phenomenon. The synoptic and thermodynamic indices indicate a high likelihood of significant precipitation occurring over Bengaluru and its surrounding regions.

Prediction of airport runway settlement using an integrated SBAS-InSAR and BP-EnKF approach

The prediction of surface settlement occupies a crucial role in achieving effective catastrophe prevention and mitigation, as well as facilitating the maintenance of airport runways. Given the challenges associated with the manual collection of settlement data and the suboptimal timeliness of the Back Propagation (BP) technique in neural networks, this study proposes an integrated prediction method that combines the Ensemble Kalman Filter (EnKF) with BP. This study focuses on the processing of Synthetic Aperture Radar (SAR) pictures obtained from the ascending orbit of the Sentinel-1A satellite. The Small Baseline Subset Interferometric synthetic aperture radar (SBAS-InSAR) technology is employed to derive the settlement time series on the runway of Kangding Airport. Moreover, three sites with high coherence within the primary settlement region are employed to assess the dependability of the model after the expansion of the data by cubic spline interpolation. The findings of the study indicate that both the BP-EnKF and BP models exhibit favorable outcomes in predicting airport runway settlement. However, following the alteration of data caused by external environmental influences, the BP-EnKF model has superior adaptability to variations in data. It has been shown that the BP-EnKF model exhibits a prediction accuracy that surpasses the BP model by 9.25%.

The Statistical Analysis of Anomalous Anticyclone in Ocean Atmosphere and Economy Based on Target Tracking Algorithm

Based on the importance of climate change in the environmental and economic fields, this study analyzes the impact of climate change on the economy based on the current situation, including the impact on sensitive industries and the impact on each district, in order to study the impact of abnormal atmospheric anticyclones on the economy. Furthermore, this study enhances the image-tracking algorithm, fuses the registered radar picture using the wavelet multiresolution analysis approach, and decomposes the registered radar image using the Mallat algorithm to retrieve the low- and high-frequency components of the image. Because the information included in the frequency components after wavelet decomposition differs, this study uses appropriate fusion algorithms for the decomposed low-frequency and high-frequency components, respectively, to produce panoramic photographs with acceptable visual effects. Through experimental research, it can be seen that the statistical analysis model of anomalous anticyclone in ocean atmosphere and economy based on the target tracking algorithm proposed in this study has a good simulation operation effect, and it also verifies that there is a certain correlation between the atmospheric anomalous anticyclone and the economy.

Iceberg Detection using Satellite Images

Chunks of ice present genuine risks for transport route and seaward establishments. Subsequently, there is a huge interest to limit them ideal and over tremendous regions. As a result of their autonomy of overcast cover and sunlight, satellite Synthetic Aperture Radar (SAR) pictures are among the favoured information hotspots for functional ice conditions and ice sheet events. The picture spatial goal for the most part utilized for chunk of ice observing changes between a couple and 100 m. Prepared SAR information are portrayed by dot clamour, which causes a grainy appearance of the pictures making the distinguishing proof of ice shelves amazingly troublesome. The techniques for satellite checking of hazardous ice developments, similar to ice shelves in the Arctic oceans address a danger to the security of route and monetary action on the Arctic rack. Along these lines, here we have thought of a thought of an application which distinguishes the Iceberg pictures utilizing satellite pictures and it is proposed by utilizing Convolutional Neural Networks (CNN) grouping.

Monitoring Glacier Changes Using Multi-Temporal Multi-Polarization Sar Images: A Review

This paper exhibits a preparing chain for the change recognition of Arctic ice sheets from multi-fleeting multi-polarization manufactured gap radar (SAR) pictures. We produce terrain corrected multi-look complex covariance information by remembering the impacts of geology for both geolocation and SAR radiometry just as azimuth slant minor departure from polarization signature. An unaided relevant non-Gaussian grouping calculation is utilized for the division of every landscape remedy Polari metric SAR picture and in this way marked with the guide of ground-truth information into ice sheet facies. We show the consistency of the division calculation by portraying the normal arbitrary blunder level for various SAR securing conditions. This enables us to decide if a watched variety is measurably critical and, in thinner, can be utilized for the post-characterization change identification of Arctic icy masses. Along these lines, the normal grouped pictures of succeeding years are looked at, and changes are distinguished as the recognized contrasts in the area of limits between ice sheet facies. For current investigations, a progression of double polarization C-band Environmental Satellite (ENVISAT) and Advanced Synthetic Aperture Radar (ASAR) pictures over the Kongsvegen icy mass, Svalbard, is utilized for exhibition.

Removing Speckle Noise in Synthetic Aperture Radar Images using Linear Filters

Speckle is a granular aggravation, typically demonstrated as a multiplicative noise that influences Synthetic aperture radar (SAR) pictures, just as every single cognizant picture. In the course of the most recent three decades, a few techniques have been proposed for the decrease of spot, or despeckling, in SAR pictures. The examination begins with the linear filtering, non-linear filtering, adaptive filtering, and hybrid filtering. In spite of the fact that the old style straight separating strategies have lower execution similarly, the hybridization between them beats than the as of late proposed techniques. Be that as it may, the cautious determination of such filters and their impacting request exceptionally influences the presentation of such filtering methodologies. In this paper, Hybrid filtering is proposed for SAR despeckling, which involves the improved variants of frost, median and mean filters. The presentation of the proposed framework is broke down and contrasted and the as of late SAR despeckling strategies. The outcomes demonstrate that the hybrid filters are focused as they can despeckle the SAR pictures superior to the current methods

Low-Cost Mini Radar: Design Prototyping and Tests

Radar systems are largely employed for surveillance of wide and remote areas; the recent advent of drones gives the opportunity to exploit radar sensors on board of unmanned aerial platforms. Nevertheless, whereas drone radars are currently available for military applications, their employment in the civilian domain is still limited. The present research focuses on design, prototyping, and testing of an agile, low-cost, mini radar system, to be carried on board of Remotely Piloted Aircraft (RPAs) or tethered aerostats. In particular, the paper faces the challenge to integrate the in-house developed radar sensor with a low-cost navigation board, which is used to estimate attitude and positioning data. In fact, a suitable synchronization between radar and navigation data is essential to properly reconstruct the radar picture whenever the platform is moving or the radar is scanning different azimuthal sectors. Preliminary results, relative to tests conducted in preoperational conditions, are provided and exploited to assert the suitable consistency of the obtained radar pictures. From the results, there is a high consistency between the radar images and the picture of the current environment emerges; finally, the comparison of radar images obtained in different scans shows the stability of the platform.

Real time prediction of track while scan data

The article covers several path prediction methods based on Kalman filter, compares mem and estimates their advantages and disadvantages on example of searching a path of a maneuvering object on noisy pre-processed radar picture by evaluating their error values.

The Influence Of Radar Picture Stabilization Type To Anti-Collision Manoeuvre Planning Accuracy

AbstractThe problem of the accuracy of anti-collision manoeuvres planning and executing at different radar picture stabilization methods (sea or ground stabilization) is described in the article. The analysis of performance standards elaborated for the radar equipment and the results of the simulation are presented. The obtained research results could be the base of discussion on the need to correct the radar equipment performance standards for easier and more appropriate interpretation of information. Basic radar utility use (for example trial manoeuvre) should be more clearly described in manuals for better and proper radar use.

Multi-Mode Radar Target Detection and Recognition Using Neural Networks

In typical radar systems, the process of recognizing a target requires human involvement. This human element makes radar systems not fully reliable due to unstable performance that varies between operators. This paper describes an intelligent radar system which addresses this problem in a border surveillance environment. The proposed radar system is capable of automatically detecting and then classifying different targets using an artificial neural network trained with the Levenberg-Marquardt algorithm. The training and test sets presented to the neural network are composed by high-resolution Inverse Synthetic Aperture Radar pictures obtained by the radar's detection module. Simulation results show that the intelligent radar system can reliably detect and distinguish the different objectives. Moreover, the radar system can outperform human operators and another radar system that deals with similar objectives. These results indicate that future intelligent systems can potentially replace human radar operators in this critical security setting.

Exceptional heavy rainfall over Ajoy, Mayurakshi and Kansabati catchments and QPF verification during flood season of September 2009

Ajoy, Mayurakshi, Kansabati are three important river catchments of West Bengal and Jharkhand state, received very heavy rainfall during two consecutive days of flood season in the month of September 2009. The contribution of heavy rainfall & combined discharges from Damodar Valley Corporation (DVC) reservoirs during the period of heavy rainspells over these catchments enhanced flood situation in some districts of West Bengal. The synoptic features based on weather charts, cloud imageries of satellite and radar pictures have been taken to analyse. The realized areal average precipitation (AAP) as per rainfall recorded at 0300 UTC of next day have also been taken to verify the quantitative precipitation forecast (QPF) of 6&7 September 2009.

Echoes of time in images of the Antarctic

British landscape artist Chris Drury imaginatively interprets radar pictures taken of ancient ice layers underneath the south pole.

Algorithms for automatically processing and analyzing aerospace pictures

This paper presents a catalog of algorithms for automatically processing aerospace pictures, including more than fifty items, systematized according to the following topics: structural comparison of images, comparison of images on the basis of Fourier invariants, alignment of images in a single coordinate system, detection of changes of the terrain on the basis of aerospace pictures, reconstruction and improvement of images, processing of information extracted from radar pictures, recognition of objects of specified classes on aerospace pictures, measurement of the elevation of objects from their aerospace pictures, searching for images in databases, geocoding of aerospace pictures, compression of images, development of camouflaging materials, and auxiliary algorithms for computing the attributes of images. The input and output data and the operating principles are briefly described for the presented algorithms.

Detection of model voids by identifying reverberation phenomena in GPR records

In order to improve the reliability of the ground penetrating radar (GPR) method in identifying subsurface sinkholes and karst cavities, laboratory investigations have been performed. The main objective of this work was to examine the relationship between horizontal/vertical voids dimensions and wavelengths of various antennas, and the corresponding GPR responses. Emphasis was given to the investigation of the factors that cause the appearance of reverberation phenomena in the signal pattern. The tests were conducted in 5 m × 10 m area by 2-m-deep trench filled with homogenous, dry sand. The voids models (empty fiberglass cylinders in diameters of 0.6 m, 1.0 m, 1.5 m and 2.4 m, with various heights) were buried vertically with their tops at depths of between 0.7 and 1.5 m. Investigations were performed for the various model conditions by towing 500, 300 and 100 MHz antennas along a pre-established grid, for the various model conditions. The GPR data collected using the 500 MHz bistatic antenna above the 1.0-m- and the 1.5-m-diameter cylinders, and using the 300 MHz bistatic antenna above the 1.5-m-diameter cylinder, confirmed the presence of a reverberation phenomenon, i.e. a strong convex signal pattern, containing a series of high amplitude extending oscillations with reduced frequency. Based on past practical GPR experience of void detection and presently obtained experimental data, two rules of thumbs may be adopted for the prediction of the appearance of resonant radar pictures: 1. The void diameter larger than the wavelength in air of the antenna used. 2. The vertical size of the empty void not significantly smaller than its horizontal dimension. The strong reverberations generated by the inner surface of the void targets were found to approximate standing waves generated in cylindrical waveguides and waveguide resonators. The theoretical, experimental and practical results obtained concur.

A case of cyclogenesis over the western Mediterranean Sea with extraordinary convective activity

AbstractAn interesting case of cyclogenesis over the western Mediterranean Sea, accompanied by extraordinary convective activity, is described in this paper. The event took place between 18 and 21 July 2001. Its synoptic features are examined on the basis of quasi‐geostrophic theory using numerical analyses from the global model of Deutscher Wetterdienst GME and from the ECMWF. Particularly remarkable is the large amount of latent heat released in the condensation process, which produces significant modifications of the flow. These effects are evident both in the fields of relative vorticity as well as potential vorticity in the upper levels. The infrared Meteosat satellite pictures are used to follow the evolution of the upper‐level cloudiness associated with the process and its connection with the values of vorticity and winds at 300 hPa. Radar pictures, reflectivity and radial velocity from Doppler surveillance radar in the Veneto region allowed us to outline the structure of the mesoscale convective system –a squall line that developed during the night of 19–20 July over Italy, in the Padana Valley. The features of this system were compared with a conceptual model proposed by Houze et al. (1989). The vertical wind shear, as inferred from the radial velocity pictures, was likely to play an important role in the development of the storm. Finally, an analysis of the vertical stability in the pre‐storm environment was performed using sounding data from Udine, 20 July 2001, 00 UTC. The analysis shows the importance in the storm development of the potential instability released by ascent during the transit of the baroclinic system, a process that was investigated using the vertical profile of equivalent potential temperature and an estimate of ascending motion given by the ECMWF model. Copyright © 2004 Royal Meteorological Society.

Determination of cloud top height using meteorological satellite and radar data

At the Hungarian Meteorological Service we receive the digital Meteosat images every 30 minutes and operate a radar network, which consists of two MRL-5 and one DWSR-25000 Doppler weather radar. The MRL-5 radar measures at 3 and 10 cm wavelengths in different ranges (32, 64, 128 and 256 km), while the Doppler radar at 5 cm in 480 km range. In this study we derive the cloud top heights (CTH) from Meteosat images and compare them with echo top values calculated from Range Height Indicator (RHI) vertical radar pictures. A cloud detection method has been developed using a threshold technique based on infrared and visible Meteosat data. The cloud top height is calculated operationally by using the infrared brightness values and ECMWF predicted temperature profiles. We got good agreement between the calculated cloud top heights and radar measurements for one-layer clouds, while bigger differences were obtained for cases, when clouds at different levels presented.

Use of Weather Radar for Combined Sewer Overflows Monitoring and Control

In the Mediterranean region, climatological factors make combined sewer overflows a major urban pollution problem that should be monitored and controlled. Some online management solutions require the use of real-time models to forecast flows at the most sensitive points of the combined sewer systems. These models need a very good time and spatial resolution of the rainfall field, which is not sufficiently reproduced by a conventional rain-gauge network. This paper presents a case study where the use of rainfall estimates from weather radar pictures is compared with the use of a rain-gauge network in terms of the ability to predict sewer flows in an urban basin in Barcelona, Spain. The results show that the use of radar data enables the combined sewer systems model to improve the reproduction of observed flows, and they provide support for the idea that the spatial description of rainfall is a key problem in modeling the events giving rise to combined sewer overflows.

Automatic stereo processing of high resolution radar imagery

Previously reported experiments with stereoscopic viewing of high resolution radar pictures demonstrated improvements in detection sensitivity up to 7 dB. This paper presents continued research into automatic algorithmic techniques for employing stereo information. A simple two-stage model for a human observer is proposed, and here we investigate the utility of an existing automatic stereo processor technique in application to radar imagery. It is shown that results obtained with the automatic processor very closely resemble those obtained through actual stereo viewing of radar pictures.

Positive identification of aircraft on airport movement area-results of FAA trials

Current operational airport surface surveillance systems do not positively identify aircraft as unique targets. Air traffic controllers are instead presented with a primary radar picture showing all traffic on the airport movement area. The Federal Aviation Administration (FAA) is evaluating different types of systems that will add the aircraft's call-sign or flight number to the radar image thereby allowing controllers to positively identify individual aircraft at all times. This paper describes the development, implementation, and testing of the airport surface target identification system (ATIDS), and presents results of initial trials conducted at Atlanta Hartsfield International Airport.

Early Radar Pictures from Magellan Yield Some Surprises

As the Magellan spacecraft orbits Venus its radar instruments are penetrating the thick clouds that prevent optical cameras from photographing the planet's surface. A portion of the Venusian surface was unveiled at a meeting of the American Geophysical Union in San Francisco in early December when mission scientists presented radar images of the planet and discussed their first tentative interpretations of what those images reveal. The images on these pages represent only a few of the strikingly diverse types of terrain that have been seen so far, with the mission having mapped only 15% of the surface.