Andrzej Chybicki

Web-Based GIS as a Tool for Supporting Marine Research

Collecting marine data during hydroacoustic research surveys is a complex task, which not only consists of measurements but also analysis, validation, and interpretation of information acquired by various sensors. Automatic integration, visualization, and processing of collected data allow for a more precise investigation of the researched phenomena. The paper presents a dedicated Web-based system for fusion and dissemination of data from satellite imagery, hydrological measurements using CTD probes, acoustic surveys by multibeam systems, side-scan sonars and singlebeam echosounders, as well as live radar feed and oil spill spread models. The system has been designed as a tool for supporting research using the aforementioned techniques.

A novel method for archiving multibeam sonar data with emphasis on efficient record size reduction and storage

Abstract Over the past few years considerable advances in sonar technology, spatial positioning capabilities and computer processing power have lead to significant improvements in mapping, imaging and technologies of seafloor exploration. Recently, modern multibeam echosounder systems (MBES) capable of recording backscatter data for the whole water column, not just for the seabed, have become available thus providing data allowing for visualization and analysis of objects other than the seabed such as single fish, fish schools or pollution. Unlike bathymetric sonars, which only capture the seafloor, multibeam systems produce very large amounts of data during surveys. Because of this, storing the data collected during hydrographic or scientific cruises becomes a crucial problem. In this context, the paper proposes a new approach for efficient reduction and storage of MBES records. The results of a sample implementation of the algorithm being tested on several different sets of MBES data are also discussed.

Innovative Web-Based Geographic Information System for Municipal Areas and Coastal Zone Security and Threat Monitoring Using EO Satellite Data

The paper presents a novel design of a web-based Safe City & Coastal Zone GIS (SCCZ-GIS). The system integrates data acquired from different remote sensing and geospatial data sources for the purpose monitoring the security of the coastal zone, its inhabitants and critical infrastructure. The system utilizes several innovative technologies and solutions and is capable of direct co-operation with different remote sensing data sources and services, including satellite ground station and ESA Service Support Environment. The system runs in operational mode, and the results of the analysis are ready in quasi real time, that is, immediately after receiving a new scene of satellite imagery. The system may be accessed by authorized users either through a web-based client or mobile device application. The paper describes the architecture of the system and presents several case studies where the software is applied to processing of earth observation satellite and spatial analysis of coastal zone infrastructure.

Seabed classification using multibeam echosounder

The method of seabed identification and classification from multibeam sonar echoes is presented. The proposed approach is based on calculation of a set of parameters of an echo envelope, similarly as in seafloor classification using single beam echosounder. These parameters are extracted for each consecutive beam allowing the estimation of their dependence on the seafloor incident angle. The relation between seabed type and calculated echo parameters and its angular dependence, is investigated. The results obtained using sonar data records from several bottom types in Gdansk Bay water region are presented and discussed.

Using angular dependence of multibeam echo features in seabed classification

The approach to seabed classification based on processing multibeam sonar echoes is presented. The multibeam sonars, besides their well verified and widely used applications like high resolution bathymetry measurements or underwater object imaging, are also the promising tool in seafloor identification and classification, having several advantages over conventional single beam echosounders. The proposed seabed classification method assumes calculation of a set of parameters of an echo envelope, similarly as in single beam classification. These parameters include echo energy, echo length, statistical moments of echo energy and the set of echo shape descriptors. They are extracted for each consecutive beam allowing the estimation of their dependence on seafloor incident angle. The characteristic features of this dependence are described quantitatively and constitute the input information for an automatic supervised seabed classifier. The results of the simple classification procedure applied for multibeam d...

Real-time Web-based GIS for Analysis, Visualization and Integration of Marine Environment Data

Visualization and integration of the marine spatial data collected by various marine sensors and sources is an important factor in the context of marine environment sensing and monitoring. Several approaches and techniques of measurements are available to achieve this purpose including direct sampling, airborne and satellite imagery, and underwater acoustics. The paper briefly describes the state-of-the art marine GIS system developed in the Department of Geoinformatics of Gdansk University of Technology, Poland. The proposed system is able to integrate many different types of marine data, especially those acquired by various acoustic sensors like multibeam sonar (MBSS), echosounder and side scan sonars (SSS), and other external sensors such as satellite data receiver, radar, or automated identification of ships (AIS) data analyzer. Instantaneous 2D and 3D visualization is provided by the two components of the system: GeoServer web-based module and a standalone application basing on ESRI ArcGIS Engine solutions.

Characterizing Surface and Air Temperature in the Baltic Sea Coastal Area Using Remote Sensing Techniques and Gis

Abstract Estimation of surface temperature using multispectral imagery retrieved from satellite sensors constitutes several problems in terms of accuracy, accessibility, quality and evaluation. In order to obtain accurate results, currently utilized methods rely on removing atmospheric fluctuations in separate spectral windows, applying atmospheric corrections or utilizing additional information related to atmosphere or surface characteristics like atmospheric water vapour content, surface effective emissivity correction or transmittance correction. Obtaining accurate results of estimation is particularly critical for regions with fairly non-uniform distribution of surface effective emissivity and surface characteristics such as coastal zone areas. The paper presents the relationship between retrieved land surface temperature, air temperature, sea surface temperature and vegetation indices (VI) calculated based on remote observations in the coastal zone area. An indirect comparison method between remotely estimated surface temperature and air temperature using LST/VI feature space characteristics in an operational Geographic Information System is also presented.

GIS for remote sensing, analysis and visualisation of marine pollution and other marine ecosystem components

Pollution detection, environment sensing and appropriate response strategies are important due to the marine ecosystemspsila continuous absorption of pollutants of various origins. Several approaches and techniques of measurements are available for marine environment monitoring including direct sampling, airborne and satellite imagery and underwater acoustics. The huge development in the information technology has provided the possibilities for much faster and more efficient access to survey data, allowing their remote, nearly real-time management, processing and visualisation. The proposed GIS is able to integrate many different types of marine pollution survey data, especially those acquired by various acoustic sensors like Multibeam Sonar Systems (MBSS), echosounder and Side Scan Sonars (SSS). It also supports instantaneous 2D and 3D visualisation in the form of thematic layers that can be overlaid. The system utilises the ArcSDE application server that facilitates storing and managing spatial data (raster, vector, and survey) in a database and ArcGIS Engine GlobeControl and MapControl components for georeferenced presentation of various objects. The set of geoprocessing and spatial analysis methods can be used in order to retrieve relevant information and analysis results.

Mapping South Baltic Near-Shore Bathymetry Using Sentinel-2 Observations

Abstract One of the most promising new applications of remote observation satellite systems (RO) is the near-shore bathymetry estimation based on spaceborn multispectral imageries. In recent years, many experiments aiming to estimate bathymetry in optically shallow water with the use of remote optical observations have been presented. In this paper, optimal models of satellite derived bathymetry (SDB) for relatively turbid waters of the South Baltic Sea were presented. The obtained results were analysed in terms of depth error estimation, spatial distribution, and overall quality. The models were calibrated based on sounding (in-situ) data obtained by a single-beam echo sounder, which was retrieved from the Maritime Office in Gdynia, Poland. The remote observations for this study were delivered by the recently deployed European Space Agency Sentinel-2 satellite observation system. A detailed analysis of the obtained results has shown that the tested methods can be successfully applied for the South Baltic region at depths of 12-18 meters. However, significant limitations were observed. The performed experiments have revealed that the error of model calibration, expressed in meters (RMSE), equals up to 10-20% of the real depth and is, generally, case dependent. To overcome this drawback, a novel indicator of determining the maximal SDB depth was proposed. What is important, the proposed SDB quality indicator is derived only on the basis of remotely registered data and therefore can be applied operationally.

Integrated visualization and analysis of threats for marine and coastal regions via a Web-based GIS

The paper presents a Web-Based Geographic Information System for integration, visualization and analysis of data on terrorist, ecological and natural threats. The system uses Open Source solutions like the GeoServer internet map server and the OpenLayers Javascript GIS client library to provide easily accessible and up-to date information related to a region of interest. The system is composed of modules which provide the following features: (1) blast and chemical attack simulation; (2) creation of hazard distribution maps; (3) analysis of risk propagation. Apart from hazard information, which maybe obtained from the simulation modules as well as inserted manually, the system collects and integrates data from several external sensors. The latter include a satellite ground station, oil spill simulation models, a radar and Automated Identification of Ships (AIS). The open, modular structure of the system allows for easy inclusion of different data sources, such as Multibeam Sonar Systems (MBSS) and echosounder. The paper presents case studies of the system applications for analysis, visualization and mapping of threats in the coastal area of the city of Gdansk, Poland.