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Categories:
Hydrographic Surveying and Marine Mappping<top of page>
- 1
>Title : NHS´Enhanced Survey Project- >Author: Stig Øvstedal, Project Manager
>Category: Hydrographic Surveying and Marine Mappping
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- Large areas of the Norwegian Coast are still covered with charts based on hydrographic data as old as 115 years. This means that the charts can be incorrect and incomplete due to that time survey methods. The public use of Global Position System (GPS) in combination with Electronic Chart System gives the navigator possibilities to use the chart in a way that are fare out of the intention it was made for. The Long Term Plan for Norwegian Hydrographic Service (NHS) is to cover the Norwegian Coast with charts that are based on modern survey methods by the end of 2006. To make this possible the Political Authorities has to increase their grant for NHS to forcing the pace. For the 2002 budget, and as it is indicated onwards, the Political Authorities will support NHS' Chart Plan.
- To be able to achieve the goal of finishing the surveys and chart production by the end of 2006, without increasing the number of employees during the project period, NHS has to purchase the services from private survey companies, private chart production companies and add sufficient consultancy resources to increase the total production capacity. The Norwegian company Blom Maritime and the German company Ocean Survey and Engineering (OSAE) are each awarded long term contracts through 2005 to do the hydrographic survey work for NHS. Blom Maritime intend to use Tenix LADS Corporation (TLC) as a sub-Contractor in the large shallow water areas. TLC is using Light Detection and Ranging (LIDAR) technique, utilising blue-green laser, for the data acquisition. The depth can fluctuate from 0 metres to 300 metres within a short horizontal distance in the Survey Areas. The great fluctuating depth demands several survey hardware platforms. The LIDAR technology can give depth to about 30 metres, EM3000 Multibeam Echosounder (300 kHz) to about 150 metres and EM1002 Multibeam Echosounder (95 kHz) to about 1000 metres. All these data are to be placed together to deliver an un-ambiguous data set for terrain modelling.
- NHS and the Contractors are facing huge challenges when the total number of planned square kilometres to be surveyed in shallow waters the first year of the contracts is about 3500.
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- 2
>Title : Multibeam Bathymetry: Sounding Ocean Floor Morphology at Continental Margins to Understand Geodynamic History- >Author: Weinrebe, W., and Greinert, J , (*)
Forschungszentrum für Marine Geowissenschaften der Christian-Albrechts-Universität zu Kiel
>Category: Hydrographic Surveying and Marine Mappping
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- In recent years, advances in swathmapping technology led to reliable and precise instruments for ocean floor surveying up to full ocean depth. Theses instruments nowadays enable geoscientists to map the morphology of the seafloor in great detail.
- During its evolution the ocean floor was shaped by depositional and erosional processes as well as by tectonic forces. Submarine morphology records the results of these processes, and imaging the morphology of the ocean floor helps to visualize their history. Submarine morpholgy is crucial in understanding ongoing geologic activity at continental margins, such as sliding and slumping.
- GEOMAR, the research centre for marine geosciences of Kiel University has carried out extensive swathmapping of large areas, in particular along active continental margins around the Pacific Ocean. Data from several cruises of german RV SONNE and RV METEOR were compiled and extended by additional data from other ships and different sources. After thorough processing and application of advanced visualization techniques maps and images of extensive areas of the continental margins off South and Central America, Oregon, Gulf of Alaska, and Japan as well as of several other oceanic areas can be presented.
- (*)GEOMAR
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- 3
>Title : Horizontallotung zur Aufnahme von Uferlinien- >Author: Hannes Lutter, (*)
>Category: Hydrographic Surveying and Marine Mappping
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM (German)- Motivation:
Zur Ergänzung der hydrographischen Messdaten in den Endprodukten wie Peilplänen sind Zusatzinformationen z.B. Uferkonturen, Wasserbauwerke etc. gute und notwendige Ergänzungen.- Leider liegen die gewünschten Daten nicht immer vor und müssen in Fällen kleiner räumlicher Ausdehnung daher meist mühsam durch terrestrische Vermessungen gewonnen werde.
Diese Art der Ufervermessung ist häufig sehr aufwändig (z. B. durch dicht bewachsenes Ufer) und erfordert zusätzliches Equipment plus qualifiziertes Personal.
In Fällen großer räumlicher Ausdehnung, kommen eigentlich terrestrische Aufnahmemethoden nicht in Frage, sondern eher die der Photogrammetrie. Die Daten sind sicher nicht in allen Fällen at hoc zu erhalten, wenn an den Planungs- Durchführungs- und Auswertaufwand gedacht wird.- Eine schnelle, relativ genaue und finanziell günstige Variante der Wasserlinienaufnahme stellt die Horizontallotung dar. Einige Vorteile sind, dass
-die Erfassung der Uferkontur parallel zur eigentlichen hydrographischen Aufnahme des Gewässerbodens erfolgen kann,
-das Ufer nicht zugänglich sein muss,
-die Aufnahmegeschwindigkeit relativ hoch ist,
-und die Punktdichte der aufgenommenen Uferdaten sehr hoch ist.
Die Qualität der Messdaten verlangen allerdings nach einer sicheren Auswertestrategie. Der beste Ansatz zur schnellen und sicheren Plausibilisierung stellt aus Sicht des Autors die polynominale Regression mit statistischen und geometrischen Testverfahren dar.- Ziel: Nutzung der Horizontallotung zur kostengünstigen Erzeugung von Uferkonturendaten
Vorgehensweise: Entwicklung einer Messtechnologie und deren Anwendung
Entwicklung einer Auswertestrategien und Umsetzung im Programm "Applaus"
Ergebnis: Im Ergebnis sind 200 km Uferkontur erzeugt worden. Ein Vergleich mit Daten aus der DBWK (Digitale Bundeswasserstraßenkarte) ergab eine hohe Übereinstimmung. Die Gesamtgenauigkeit von besser 1,5m ist durch die integrierte Protokollierung aller Plausibilisierungsschritte im Programm "Applaus" nachzuweisen.- (*)WSA Stralsund
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- 4
>Title : Image Processing and Mapping of Coastal Sediments by Side Scan Sonar- >Author: Hannelore M. Fiedler & Doris Milkert (*)
>Category: Hydrographic Surveying and Marine Mappping
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- Side Scan Sonar (SSS) as a method of acoustic remote sensing is widely used for mapping sediments and seafloor structures. SSS provides pictures of the seafloor comparable to aerial photographs. Recent technological advances in SSS systems have brought the objective of complete mapping of the seafloor into the mind of researchers.
- The recorded data are used in the digital domain to process images. Special computer techniques are used to correct and manipulate these data to focus on the specific characteristics in the sonar pictures. The processing software (in this case Triton Elics) includes the removal of the water column, time-varied gain (TVG) processing, slant range and beam pattern correction. Additional small jitters in time and position are filtered out to get cleanest single line mosaic view as possible without loosing relevant information about sediments and resolution.
- The survey of an area includes several single profiles, run on parallel tracks with a certain amount of overlapping. The single profiles are fed into a geographical information system (GIS) and combined to a mosaic.
- A sediment classification scheme based on the mosaic can be performed by discriminating the differences in acoustic backscatter from surface roughness. Additional information about the bathymetry from an echo sounder system and the seismic information from a subbottom profiler can be added to the GIS and mosaic. Some examples are given.
- (*)Federal Armed Forces Underwater Acoustics and Marine Research Institute, Klausdorfer Weg 2-24, D-24148 Kiel, Germany, email HanneloreFiedler@bwb.org
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- 5
- >Title: Investigation of iceberg scour marks on the south eastern Weddell Sea Shelf off Austasen
- >Author: Constanze Hohmann (*)
>Category:Hydrographic Surveying and Marine Mappping- >Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The overall objectives of our impact studies of grounding icebergs on benthic and fish fauna were related to the EASIZ program (Ecology of the Antarctic Sea Ice Zone) of SCAR (Scientific Committee on Antarctic Research). Field studies were conducted during POLARSTERN cruises in 1996 (EASIZ 1), 1998 (EASIZ II), and 2000 (EASIZ III). Several joined projects investigated different aspects of disturbance.
One project dealt with the physical influence of grounding icebergs on Antarctic ben-thos and fish communities. Supported by remotely operated vehicles (ROV), multibox corers (MG) guided by attached underwater (UW) cameras, Agassiz and Otter Trawl and the multibeam echosounder HYDROSWEEP DS-2 areas have been sur-veyed, where supposedly benthic environments were devastated by grounding icebergs.
The area under study was Austasen, located on the south-eastern Weddell Sea shelf north-east of Kapp Norvegia. Due to previous studies this area was already known as being intensely affected by dense accumulations of grounding icebergs (so called cemeteries or resting places). The Hydrosweep DS-2 System was used to find scour marks, which later were surveyed by the various other gears.
Hydrosweep data from 79 scours were analysed in a framework of a diploma thesis. These data describe the morphology of scour marks, i.e. the size, extension and ex-cavations. Biological studies carried out on some of the analysed scour marks also related sharp gradients in the community structures as indication of disturbance by grounding icebergs at these spots.- (*) AWI Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany chohmann@awi-bremerhaven.de
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- 6
>Title : Analyses of High Resolution Bathymetric Data in the Eltanin Impact Area- >Author: Merijn Jacops,(*)
>Category: Hydrographic Surveying and Marine Mappping
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
One of the research projects of the Alfred Wegener Institute for Polar and Marine Research, in the last years, was the Eltanin Impact Area, situated in the Bellingshausen Sea. This Eltanin Impact Area is yet the only known impact area affecting the deep ocean basins.
During two expeditions, in the year 1995 (ANTXII/4) and 2001 (ANTXVIII/5a), with the German Research Vessel 'Polarstern' this area was systematically surveyed, and bathymetric data were collected. The main tasks of this research project were the derivation of a high resolution and accurate digital elevation model of the Eltanin Impact Area, and second the backscatter processing and analyses. The research project and the results will be presented during this symposium.- Different steps were undertaken for the computation of a digital elevation model (DEM). The data editing and cleaning was performed using the software HIPS of the GIS program CARIS. These data were used within ArcInfo to compute the DEM. Within ArcInfo different methods for the computation of a digital elevation model were analysed.
Finally the inverse distance weighting interpolator was used to compute the DEM. Because of the noise that was present after the computation, a slope depending filtering was performed to reduce these effects. For the filtering binomial filters were used. Finally a DEM could be computed within the accuracy of the multibeam system, 0.5% of the water depth.- During the two expeditions the multibeam system Hydrosweep DS-2 not only collected the bathymetric data, but also backscatter strengths data. These data were analysed for an interpretation of the bottom roughness and bottom type within the Eltanin Impact Area. With the use of the computed digital elevation model the two important parameters for backscatter analyses, the backscatter strengths and the incidence angle, were computed. These data were combined for response curve analyses. Within ArcInfo a segmentation was performed using an unsupervised classification. This segmentation of the backscatter data, using the response curve analyses, proved to be successful. A global interpretation of the different roughness of bottoms, and bottom types, could be made, also in comparison with the digital elevation model of the Eltanin Impact Area. However for a full view and better analyses of the backscatter data, the analyses of ground truth data, grain size and bottom type of the upper sediment layer, is very crucial.
- (*) Alfred Wegener Institute for Polar and Marine Research
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7
>Title : DSLP - A GREATER DEPTH OF KNOWLEDGE- >Authors: Hendrik Eden, Volker Müller, Dirk Vorrath (*)
>Category: Hydrographic Surveying and Marine Mapping
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The demands on the expressiveness of bathymetric surveys has become of growing importance within the last years. Precise estimation of the nautical depth, especially in harbour basins, channels, waterways and other restricted areas and also detailed information about the stratification of the uppermost sediment layers is expected. Background of these demands are the rising costs of dredging operations for waterway maintenance as well as port development. The DSLP® echo sounder method is a new revolutionary method in hydrographic surveying. The abilities and performance of DSLP® was proved in each survey. In practice DSLP® provides a depth resolution of 3cm concerning the unambigious detection of the solid bottom - the interfacial layer between liquid and solid. This extraordinary performance is also achieved in stratified suspension layers as in weak and tight consolidated sediments - physically proven. The DSLP® echosounder's outstanding abilities lead into a new measurement- and verification quality of material states, essentially important for determining near bottom dynamic sediment transport processes. Common acoustic methods are not able to differ unambigious between suspension- and hard bodies. There for they are not able to identify the interfacial layer between liquid and solid state. The most remarkable difference between DSLP® and common echo sounders is the DSLP's independency of the utilized frequencies, so DSLP® is also independent of the results of other accompanying measurements or core probes. Under all conditions DSLP® gives a clear result of the interfacial layer between liquid and solid. The concept of the DSLPâ-method differs in two main parts from conventional echo sounder technology. At first using sound impulses out of a broad frequency range as a stimulating sound to trigger distinct interaction processes between sound wave and material. Secondly, the recorded signals will be analysed and evaluated with a complex signal analysis. The result from this data analysis is independent from the utilised frequencies, but it is characteristic for such a processes. This makes it possible to detect suspensions- and sediment layerings on the basis of a physical proof.
- Actual results on surveying by the DSLP® - echosounder will be presented.
- (*) EDEN, VORRATH & PARTNER, Dorfstr. 57, 24107 Ottendorf , Germany FON +49 431 580 8180 FAX +49 431 580 8189INFO@E-V-UND-PARTNER.DEWWW.E-V-UND-PARTNER.DE
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- 8
>Title : Schillig Reede (Jade, North Sea) - a Side Scan Sonar Mosaic- >Authors: Hannelore M. Fiedler & Doris Milkert (*)
>Category: Hydrographic Surveying and Marine Mapping / Poster
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- Side scan sonar with additional sediment sampling was performed on a 1200 m x 900 m grid based on 13 profiles at 120 m distance. The data set was processed by using the Triton Elics ISIS programme package. Specific characteristics in the sonar pictures were enhanced by various processing steps, fed into a geographical information system (GIS), and combined to a mosaic.
- The displayed backscattering values on the side scan sonar picture clearly show sanddunes with rippels.
- (*)Federal Armed Forces Underwater Acoustics and Marine Geophysics Research Institute, Klausdorfer Weg 2-24, D-24148 Kiel, Germany, email HanneloreFiedler@bwb.org
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9
>Title : Fram Strait Bathymetry, A high resolution DTM and contour set from R/V Polarstern multibeam data- >Author: Martin Klenke & Hans Werner Schenke (*)
>Category: Hydrographic Surveying and Marine Mapping / Poster
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
Based on data from R/V Polarstern multibeam sonar surveys between 1984 and 1997 a high resolution bathymetry has been generated for the central Fram Strait. The area ensonified covers approx. 36,500 km² between 78°N - 80°N and 0°E - 7.5°E.
Basic outcome of the investigation is a raster Digital Terrain Model (DTM) with 100 m grid spacing which was utilized for contouring and generation of a new series of bathymetric charts (AWI Bathymetric Charts of the Fram Strait, AWI BCFS) at a scale of 1:100,000.
Our poster gives a short introduction to the regional setting and relevance for local and global climate trends followed by a description of the input data and processing applied. Thereafter the bathymetric features of the area are characterised. Finally the generated data products available for public disposal are described.- More information can be found under http://www.awi-bremerhaven.de/GEO/Bathymetry/framstr/framneu.html.
In case of questios, please contact Martin Klenke.
- (*) Alfred Wegener Institute for Polar and Marine Research
P.O.Box 120161, D-27515 Bremerhaven, Germany, Tel.: +49 (0) 471 4831 1167, Fax: +49 (0) 471 4831 1149, mklenke@awi-bremerhaven.de- <top of page>
10
>Title: Surveying the "Jadebusen" as an example of hydrographic surveys for multiple uses- >Author: Thomas Dehling, Bernd Vahrenkamp,(*)
- >Category: Hydrographic Surveying and Marine Mapping / Poster
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
One very important user of hydrographic surveys done by the Hydrographic Offices is traditionally the nautical cartography. They are used for chart production. But the Tasks of the Federal Maritime and Hydrographic Agency (BSH) can not be reduced to navigation. The scope is rather widening (e.g. CZM, coastal protection, coastal engineering). More and more different demands are made by the users. This leads to hydrographic surveys for multiple uses. How to fulfill the needs of different users with just one survey campaign is shown by an example.
In 2001 the "Jadebusen" had to be surveyed for the BSH as well as for special coastal engineering purposes. This meant high and quite different criteria for accuracy, vertical reference and processing. Multi-beam, single-beam and laserscan data had to be combined.
In this paper planning, execution and processing of the surveys are being described with a focus on height correction with PDGPS and on the combination of seaborne and airborne data. Problems and solutions are being discussed.- Kurzfassung:
Seevermessung für multiple Zwecke am Beispiel der Vermessung des Jadebusens 2001
Die Vermessungen des Meeresbodens durch die hydrographischen Dienste haben als einen wesentlichen Nutzer die eigene nautische Kartographie. Sie dienen damit der Herstellung von Seekarten. Die Aufgabe des Bundesamtes für Seeschifffahrt und Hydrographie ist jedoch nicht auf die Seeschifffahrt beschränkt, vielmehr erweitert sich der Kreis der Nutzer ständig. Ich nenne hier nur die Schlagworte "Küstenzonenmanagement", "Küstenschutz" und "Küsteningenieurwesen".
Alle Nutzer stellen unterschiedliche (und ständig steigende) Anforderungen an die Ergebnisse der Seevermessung. Daraus ergibt sich die Anforderung einer "Multi-User-Seevermessung". Wie die Qualitätsanforderungen verschiedener Nutzer durch nur eine Vermessungskampagne erfüllt werden können und welche Probleme dabei auftreten, soll an einem Beispiel dargestellt werden.
2001 sollte der Jadebusen sowohl für das BSH, als auch für die Bundesanstalt für Wasserbau vermessen werden. Dabei waren hohe und völlig unterschiedliche Anforderungen an Genauigkeit, Bezugsfläche, Auswerteverfahren zu erfüllen. Es wurden Vertikal- und Fächerlotungen kombiniert. Darüber hinaus wurden Wattflächen mit dem Laserscan-Verfahren vermessen.
Der Vortrag behandelt die Planung, Durchführung und Auswertung der Vermessungen. Schwerpunkte bilden dabei die Beschickung mit Hilfe von DGPS und die Verbindung von seegestützten hydrographischen Vermessungen und luftgestützten Laserscandaten.
Die besonderen Probleme und Lösungen werden aufgezeigt.- (*) Bundesamt für Seeschifffahrt und Hydrographie
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Multibeam Echosounding systems<top of page>
- 11
>Title : Automated Techniques for Multibeam Processing- >Author: Harold Orlinsky (*)
>Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
Processing multibeam data unfortunately is very time consuming. Producing upwards to 20 million soundings a day, for a typical 8-hour survey period, the data set can become overwhelming to process. Unlike the single beam method, where the operator has the opportunity to examine and verify each data point, the multibeam system's vast amount of data makes the same procedure unrealistic. A new approach to examine the multibeam data has been developed and refined over the past decade uses an automated methodology to process the data set. With little user intervention, the automated techniques can examine the survey data; rejecting flyers and applying all correctors needed for the data can be processed in a short period of time.
Because the automated processing does not allow the operator to see the data as in traditional methods, a greater confidence must be given to the validity of the data being accepted, as well as those data points to be rejected. The filters and gradients applied to the data set needs to be done without losing any features from the seafloor.
To demonstrate some of the automated techniques, multibeam data sets collected over the past year will be examined. These include:
· A high-resolution shallow water survey in Portsmouth Harbor, NH,
· Reef and wreck investigations along the coast of Toulon, France
· Detailed anchor block mapping along the Hood Canal Bridge in Washington. This project presents a classic example of detecting data flyers. A steep gradient, from one beam to another appears at the intersection of the anchor block and seafloor. The key is determining whether the software interprets the data as flyers, or a submerged object.
Other data sets will be examined, and in each case, it will be shown that the timesavings when using the automated processing mode is significant when compared to more traditional methods. To be fair, errors that occurred while processing including data fliers that had remained in the final data set will also be shown.- (*) Triton Elics International
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- 12.1
>Title : Application of Multibeam Echo Sounders for Securing Safe Navigation on Rivers and Canals- >Authors: Freddy Pøhner, Morten Jacobsen,(*)
>Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
High frequency multibeam echo sounders are now taken into use for precision mapping of the German waterways, in order to secure the safe navigation of vessels of all kinds on the rivers and canals. Such mapping poses new and strict requirements for the survey procedures as well as the data processing and visualisation tools. The paper deals with the methods which have been taken into use for vertical height control of the surveys, as well as the tools for data verification and elimination of incorrect soundings.
Some real examples of survey data are used to illustrate the principles.- (*)Kongsberg Simrad AS Norway, Steffen Pausch, Simrad GMBH
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- 12.2
>Title: New Technology for Single Beam Echo Sounding- >Authors: Freddy Pøhner, Torbjørn Kjær, Knut Terje Ulvund(*), Steffen Pausch,(**)
>Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
During the last years, most of the focus for survey technology development has been directed towards multibeam echo sounders and swathe mapping systems. However, some important developments are at the same time taking place for the vertical echo sounding. The paper deals with innovations of some new single beam echo sounders, such as
· multiple hypothesis bottom detection algorithms
· archiving of digital echograms not on rolls of paper, but as well organized files in a digital archive
· New challenges and opportunities when the echo sounder becomes a windows based computer system:
· Integration of survey control systems and echo sounders into one unit
· Real time analysis of the acoustic signals to characterize the bottom sediments- (*)Kongsberg Simrad AS Norway, (**) Simrad GMBH
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- 13
- >Title: " Multibeam technology - special applications for wide swath survey systems"
- >Author: Peter Gimpel, (*)
>Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- Multibeam surveying has become a standard method of acquiring high quality hydrographic data with 100% bottom coverage both in shallow and deep water. Highly accurate depths, backscatter information and quality indicators are standard output parameters of such a swath system.
- Due to increasing processing and storage power of modern PC based data acquisition computers no data reduction within the sonar real-time processor is required and allows for additional data evaluation of "raw" data.
- Applications of this special processing - estimation of volume backscattering within the water column - were discussed and presented.
- (*) L-3 Communications ELAC Nautik GmbH, Kiel, Germany
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14- >Title: A comparison of Shallow Water Multibeam Systems from a commercial viewpoint.
- >Author: Duncan Mallace, (*)
>Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- There are now almost as many shallow water multibeam systems as there are sidescan sonars, with varying levels of sophistication and price. One of the main areas of debate is in the performance between interferometric multibeam systems and digital beamformers. Interferometric systems are based on less advanced technology and therefore are substantially cheaper than digital beamformers, but is the accuracy and performance adequate for today's hydrographic survey standards? Are there specific areas where a digital beamformer has to be used? This paper uses the data collected for the Shallow Survey Conference in New Hampshire (Sept 2001) as the basis for the comparison. The data was collected either by reputable survey companies/organisations or the manufacturers themselves with a differing array of peripheral sensors. To this end this is not definitive but will serve as a guideline in the use of shallow water multibeam systems. The systems compared are Kongsberg Simrad EM3000D, Reson 8101, Reson 8125, Seabeam ELAC 1185, GeoAcoustics GeoSwath, Submetrix, Odom Echotrac and Atlas Fansweep 20. The data was processed by the author using CARIS HIPS post processing software.
- (*)NetSurvey Limited, UK
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- 15
- >Title: Methoden für die qualitätsgesicherte Auswertung von Fächerlotdaten
- >Author: Dipl.-Ing. Harry Wirth (*)
- >Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- Zusammenfassung
Das Referat (M5) der Bundesanstalt für Gewässerkunde berät die Wasser- und Schifffahrtsverwaltung (WSV) in allen technischen Aspekten der Gewässervermessung. Mit Einführung von Fächerloten sind die Anforderungen an die Auswerteverfahren auch im Binnenbereich extrem angestiegen. Ursache ist einerseits der enorme Anstieg der Datenmenge und andererseits vor dem Hintergrund der Einführung von nautischen Informationssystemen und Weitergabe der Tiefeninformationen an die Schifffahrt der Bedarf an gerichtsfesten, qualitätsgesicherten Daten.- Die BfG hat die Software HyDAP (Hydrographische Datenauswertung und Präsentation) entwickelt, um den Auswerteprozess in hohem Umfang zu automatisieren und den Auswertern die Erzeugung eindeutiger und wiederholbarer Qualitäten, sowie durchgreifende Qualitätsnachweise zu ermöglichen.
- Im Vortrag werden die Methoden anhand Beispielen aus der Praxis erläutert.
- Insbesondere soll das automatische Verfahren der Flächenplausibilisierung vorgestellt werden. Au-ßerdem werden die umfangreichen Möglichkeiten der Modellierung und Qualitätssicherung visualisiert.
- (*) Referent Dipl.-Ing. Vermessungsoberrat, Harry Wirth, Ansprechpartner für Gewässervermessung, c/o Bundesanstalt für Gewässerkunde Koblenz
Kaiserin-Augusta-Anlagen 15-17, 56068 Koblenz- <top of page>
- 16
- >Title: Processing, Analysing and Visualisation of Multibeam Data from Different Systems Gathered during the AMORE-Expedition to Gakkel Ridge
- >Authors: Steffen Gauger, Thomas Hartmann, Joern Hatzky, Hans Werner Schenke ,(*)
Bremerhaven, Germany
>Category: Multibeam Echosounding systems
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The Gakkel Ridge in the central Arctic Ocean was object of an international expedition in the summer 2001. This part of the Mid-Ocean-Ridge-System is of particular geoscientific interest because of its extremely slow spreading rates and the variety of morphologic forms and features that are produced in this tectonic environment. Therefore, the multibeam bathymetric measurements were of special importance to the scientific goals of the exploration of this deep-sea ridge. The data was collected in the frame of a two-ship expedition by RV ,,Polarstern'', equipped with the multibeam echosounder Hydrosweep DS-2, and by USCGC ,,Healy'', which utilised a Seabeam-2112 multibeam system for the seafloor survey. This contribution deals with data editing and cleaning using CARIS HIPS. For the digital terrain modelling and mapping of the seafloor topography appropriate ArcInfo tools were
used. A comparison of the results from the two utilised multibeam systems will be presented. Finally products in form of bathymetric charts prepared with ArcMap in the western part of the Gakkel Ridge will be shown.- (*)Alfred Wegener Institute for Polar and Marine Research
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Marine Monitoring<top of page>
- 17
- >Title: Upgrading of MARNET-technology by event controlled samplers for organic contaminants and automatic pump photometers for nutrient measurements
- >Authors: Herklotz, K., S. Schwarz and H. Nies, (*)
>Category: Marine Monitoring
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The project SAMSON was launched to continue the development of chemical sensors for nutrient measurements and automatic samplers for organic micropollutants. It is integrated in the monitoring concept of the German Federal Maritime and Hydrographic Agency (BSH) which operates the "Marine Monitoring Network in the North and Baltic Seas" (MARNET). While conventional concentration measurement methods based on samples taken by research vessels are not suitable for an acceptable temporal resolution and are very expensive, the automatic analysers and automatic samplers allow effective, cost-efficient sampling strategies with high sampling rates.
A new prototype of an automatic sampler for organic contaminants (EPOS) is presented. The sampler is designed for an easy handling during maintenance of the sea based stations. Sampling of sea water can be carried out regular or for a spot view and therefore be initialized by either a well defined event or via GMS telemetry by the shore based station. The sampler consists of six exchangeable filtration and extraction units. Separation of liquid and solid phase is performed by filtration followed by solid phase extraction of the liquid phase. Different sample volumes and the adsorber materials are eligible. Analysing of samples will be carried out after each service cruise in the laboratories of the BSH. First results of the test phase could be presented.
Nutrient concentration measurements by automatic pump photometers (APP) are advanced and the quality of the measurements has been improved. The method for silicate determination is now integrated and a prototype of an APP for ammonia measurements based on a fluorometric measuring method is presented.
Scientific analysis of the nutrient data sets accompanies the technical development within SAMSON. Time series of nutrient concentrations comprising four years (from 1998 until 2001) with 1 hour resolution. Therefore they present an adequate description of the nutrient situation in hydrographically highly variable sea areas. This includes investigation into the seasonal and short term (i.e. tidal) dynamics of nutrient concentrations in relation to the oceanographical and meteorological variables, as we show in some representative examples. Among the German Bight another highly variable sea area is the Belt Sea, the transition zone between Kattegat and Baltic Sea. An automated monitoring station collecting nutrient data at 6 m and 23 m depth has been in operation since the summer of 2001 and amend the environmental monitoring of the BSH.- (*) Bundesamt für Seeschifffahrt und Hydrographie (BSH) D-20305 Hamburg, Germany
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- 18
- >Title: Upgrading of MARNET-technology by event controlled samplers for organic contaminants and automatic pump photometers for nutrient measurements
- >Author:Herklotz, K., S. Schwarz and H. Nies, (*)
>Category: Marine Monitoring
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The project SAMSON was launched to continue the development of chemical sensors for nutrient measurements and automatic samplers for organic micropollutants. It is integrated in the monitoring concept of the German Federal Maritime and Hydrographic Agency (BSH) which operates the "Marine Monitoring Network in the North and Baltic Seas" (MARNET). While conventional concentration measurement methods based on samples taken by research vessels are not suitable for an acceptable temporal resolution and are very expensive, the automatic analysers and automatic samplers allow effective, cost-efficient sampling strategies with high sampling rates.
A new prototype of an automatic sampler for organic contaminants (EPOS) is presented. The sampler is designed for an easy handling during maintenance of the sea based stations. Sampling of sea water can be carried out regular or for a spot view and therefore be initialized by either a well defined event or via GMS telemetry by the shore based station. The sampler consists of six exchangeable filtration and extraction units. Separation of liquid and solid phase is performed by filtration followed by solid phase extraction of the liquid phase. Different sample volumes and the adsorber materials are eligible. Analysing of samples will be carried out after each service cruise in the laboratories of the BSH. First results of the test phase could be presented.
Nutrient concentration measurements by automatic pump photometers (APP) are advanced and the quality of the measurements has been improved. The method for silicate determination is now integrated and a prototype of an APP for ammonia measurements based on a fluorometric measuring method is presented.
Scientific analysis of the nutrient data sets accompanies the technical development within SAMSON. Time series of nutrient concentrations comprising four years (from 1998 until 2001) with 1 hour resolution. Therefore they present an adequate description of the nutrient situation in hydrographically highly variable sea areas. This includes investigation into the seasonal and short term (i.e. tidal) dynamics of nutrient concentrations in relation to the oceanographical and meteorological variables, as we show in some representative examples. Among the German Bight another highly variable sea area is the Belt Sea, the transition zone between Kattegat and Baltic Sea. An automated monitoring station collecting nutrient data at 6 m and 23 m depth has been in operation since the summer of 2001 and amend the environmental monitoring of the BSH.- (*) Bundesamt für Seeschifffahrt und Hydrographie (BSH), D-20305 Hamburg, Germany
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- 19
>Title: Possibilities of marine algae group detection tested in the German "Blue-Box-Project"- >Author:Klaus Heinrich Vanselow and Andreas Ruser (*)
>Category: Marine Monitoring
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- BMBF (German Federal Ministry for Education and Research ) promotes for nearly three and a half years the research and development project "Measuring System for Ferries" (Blue Box). It was initiated by Prof. Koske at the Institute of Applied Physics (IAP). From 1999 it was carried on at the Zentrum für Angewandte Meereswissenschaften (ZAM). The project concluded a low-priced flow-through system, that contains CAN-Bus recorded sensors in a ferries qualified and seawater consistent unit. At time the following sensors are available: temperature, conductivity, turbidity, oxygen, chlorophyll and pH. The industry partner in the project GO-Systemelektronik GmbH (Kiel) makes the Blue Box System in first prototypes available.
- Project part of the FTZ is to integrate a marine algae group detection in the Blue Box project by fluorometric analysis methods. This was done by using the limnological calibrated Algae-Online-Analyser (AOA) from the factory partner BBE Moldaenke GmbH (Kiel). The unit was tested, varied and adapted to the Blue Box by considering the marine environmental conditions of the German Bight.
- The algae group detection is based on actinic light sources at 5 different wavelengths in the PAR window of the sun spectrum and the detection of chlorophyll fluorescence response at the wavelength region from 680 to 720 nm. The light answers were compared with the known spectral values of different algae groups (fingerprints) [1-4]. The different parts of algae groups in the water sample are detectable by a fit algorithm (Gauss-Jordan-Elimination). A quality check of the measured value - fingerprint comparison is realised by a fit-quality criterion. The elimination of dead fluorescent material gives a better fit-quality, so that a further split up of the brown spectral group is possible if the actinic irradiation wavelengths were changed for a better discrimination of diatoms and dinoflagellates. By changing some hardware components of the AOA a discrimination within the brown spectral group was realised in our laboratory [4].
As result of our investigations, the Blue Box AOA works with four fingerprints for the German Bight. The fingerprints are taken from pheophytin, diatoms, dinoflagellates and cryptophyceae [4]. The laboratory experiments must be confirmed by field experiments.- Literature Cited:
[1] RUSER, A., POPP, P., KOLBOWSKI, J., RECKERMANN, M., FEUERPFEIL, P, EGGE, B., REINEKE, C. & K. H. VANSELOW (1999): Chlorophyll-fluorescence-based measuring systems for the detection of algal groups and the determination of chlorophyll-a concentrations - a comparison. In: Ergebnisse des 2. Workshops "Primärproduktions-be-stimmungen in aquatischen Systemen" in Büsum vom 5.-8.10.98. Hrsg.: P. Hartig & K.H. Vanselow, Berichte a. d. Forschungs- u. Technologiezentrum Westküste d. Univ. Kiel., Nr. 19: 27-38.
[2] RUSER, A. & K. H. VANSELOW (1999): Automatische Algengruppenerkennung mit fluoro-metrischen Meßmethoden. Mitteilungen der Deutschen Gesellschaft für Meeres-forschung, Nr. 3/99: 14-15.
[3] RUSER, A. & K. H. VANSELOW (1999): Algen automatisch erkennen. Ergänzt von H.-J. Neubert. Informations-dienst Wissenschaft (idw) unter http://idw.tu-clausthal.de und bei AlphaGalileo unter http://www.alphagalileo.org.
[4] RUSER, A. (2001): Untersuchungen zur Erkennung von Algengruppen und deren photosynthetischer Aktivität im marinen Bereich. Dissertation in: Berichte a. d. Forschungs- u. Technologiezentrum Westküste d. Univ. Kiel, Nr. 25: 206 Seiten.- (*) Research and Technology Centre Westcoast of University Kiel,
Hafentörn, D-25761 Büsum, Germany- <top of page>
- 20
- >Title: Monitoring sediment transport
- >Authors: Dr. R.L. Koomans1 , E. Oosterhoff, Dr. J. Limburg
>Category: Marine Monitoring
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- Determining the transport of sediment is an important issue in the assessment of the effectiveness and environmental effects of open-water dredge-spoil depots and underwater beach nourishments. Thus far monitoring has mainly been carried out by point measurements of sediment-transport processes or by using sediment traps placed for some time on the bottom. Both methods have serious drawbacks. Point measurements provide only limited information and sometimes require ambiguous extrapolations. With the development of systems that provide high-resolution quantitative information of morphology and sediment composition, we are able to measure and quantify the net effect of sediment transport.
With successive measurements with a multibeam system, changes in morphology can be determined. However, the uncertainty in these determinations of water depth (typically 15-30 cm) prohibits the monitoring of dispersion of sediments from an underwater depot or beach nourishment at large distances.
With the recent development of the MEDUSA detector system, it has become possible to measure small changes in sediment composition. MEDUSA is a detector system that utilizes variations in the content of natural radionuclides between sediments. The system is towed over the sediment behind a vessel and determines the sediment composition (e.g. sludge concentration, grain size or heavy-mineral concentration) each second. The integral combination of multibeam and the MEDUSA system in a monitoring campaign quantifies sediment transport.
Besides an assessment of the used approach, the paper will present two case studies. One case study focuses on monitoring dredge spoil from an open water depot; the other study focuses on quantifying the effectiveness of an underwater beach nourishment.
- 1 MEDUSA Explorations BV, PO box 623, 9700 AP, Groningen, The Netherlands, tel: 0031(0)505770280, fax: 0031(0)505772534 Koomans@medusa-online.com.
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- 21
- >Title: Ocean Wave and Current Remote Sensing, System concept and performance of the modular HF-Radar system WERA
- >Author:Thomas Helzel, Matthias Kniephoff, Oliver Kohse (*)
>Category: Marine Monitoring
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The WERA system (WavE RAdar) is a remote sensing system based on short radio wave radar technology, operating with very low power. The system output are wave and current parameters over a distance of more than 100 km with a spatial resolution of down to 300 m and a time resolution of 10 minutes.
The system concept of WERA based on a development carried out at the university of Hamburg. WERA is a frequency modulated, continuous wave (FM-cw) radar, transmitting a continuously swept radio frequency (rf) signal. The received signal, reflected by the waves, has a frequency offset compared to the actual transmitted signal. The frequency offset is a measure of the distance between antenna and the waves and the wave parameters are modulated onto this carrier signal. The rf is transmitted by means of a 4-antenna array and received with a similar array for current mapping only or with a linear array of 8, 12 or 16 antennas for the measurement of ocean wave fields.
The advantages of the FM-cw principle are the low rf-power requirement to get best signal to noise performance, nearly no blind range in front of the antennas and a low sensitivity to external rf noise sources. The key components to build a FM-cw radar are an excellent reference oscillator with best short term stability, a low phase noise and ultra linear sweep generator and a high dynamic range receiver and analogue to digital converter.
The WERA system is set up modular with high performance components to get the best performance that can be achieved with industrial standard today. This results in a Spurious-Free-Dynamic-Range of more than 100 dB. The integrated system controller carries out the first data reduction algorithm and provides the raw data for post processing on any external computer. This free access to the raw data is important for research applications. For the commercial user a professional user interface and all required support for the installation are provided.- (*) Helzel Messtechnik GmbH, Carl-Benz-Str. 9 , D-24568 Kaltenkirchen , Germany, Tel.: +49 - 4191 - 95 20 31, Fax: +49 - 4191 - 95 20 40 , e-mail: helzel@helzel.com
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- 22
- >Title: The NAUTISONDE - a newly developed probe for rheological in-situ sediment characterization
- >Author:Dr. Wolfgang Dasch (*)
>Category: Marine Monitoring
>Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM
To enable better judgement of the sludge situation in areas of fluid mud it has to be mentioned that the main contolling parameter is the VISCOSITY. Often usual methods of echo sounding for depth measurements produce diffused echos of no use in mud layers or in suspensions of high concentration. Under these reflection conditions, sounding methods are not satisfactory for the estimation of the sediment concentration or the navigable depth.
Until now, to get more information about mud consistency, measurimg the density by the use of a gamma probe was the only practicable method. This procedure not only requires a strong gamma emitter for quick measurements but also a lot of laboratory work to correlate the density data with rheological properties (mostly the yield stress).
By the use of the newly developed NAUTISONDE rheological properties are DIRECTLY IN-SITU measurable. The profiling probe delivers a >rheological cut< of the suspension ® fluid mud ® sediment column. It will be shown that the obtained data are easily connected to yield stress measurements formerly used to define the navigable depth. Applying the NAUTISONDE the nautical horizon is easily determined and further investigations of muddy areas like upsilting, consolidation or erosion is in-situ measurable using rheological properties as the leading parameter.- (*) Consulting Dr. Dasch , Dorfstr. 18a D - 24254 Rumohr
- Tel.: +49 - 43 47 - 46 70 FAX: -49 - 43 47 - 71 09 73 , URL: http://www.dasch.de
- e-mail: wd@dasch.de
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Coastal Zone Management<top of page>
- 23
- >Title: Hydrographic Survey Approaches to Wrecksite Management: Transforming charted obstructions into valuable cultural resources
- >Author:Jeremy B. Weirich,(*)
>Category: Coastal Zone Management- >Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- With the increase of diverse technology and sophisticated remote sensing equipment, the hydrographic community in the US, particularly the National Oceanic and Atmospheric Administration (NOAA), is inundated with non-traditional requests for its data. One such community trying to benefit from this technology is cultural resource managers (CRM) for use in shipwreck verification and long-term site preservation. Unfortunately there is often a communication gap between the two groups in terms of what CRM's need and what hydrographers can provide them, with CMR's typically underestimating the types of information that can be acquired.
- Over the years, NOAA hydrographers have developed a systematic approach to locating shipwrecks through side scan sonar imagery, multibeam bathymetry and first-hand diver verification. With additional project planning, hydrographers can approach a cultural- based survey with the CRM's needs in mind, primarily during the product presentation stage. Cooperative ventures in Thunder Bay, Michigan and Delaware Bay, Delaware, have proven that cultural projects organized by hydrographers are thorough, efficient, and meaningful. It is through side expeditions like these that hydrographers have found new customers and additional avenues to disseminate their data.
- (*) LTJG/NOAA
- U.S. Department of Commerce, National Oceanic and Atmospheric Administration
NOAA Ship Whiting, 439 W. York Street, Norfolk, VA, 23510, USA
Work: (757) 441-6322 Cell: (617) 875-4658
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- 24
- >Title: EXTENDING THE ECDIS TECHNOLOGY TOWARDS PORT AND COASTAL ZONE MANAGEMENT
- >Author:Bohdan Pillich (*)
>Category: Coastal Zone Management- >Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- ECDIS has been developed for navigational purposes but should be regarded as a Marine Information System. Its data structure makes it useful for general GIS, such as the port or coastal management and information. It is a digital information system with the capability to combine a wide range of four-dimensional oceanographic and coastal data to create environmental scenarios adaptable to a wide range of uses.
- ECDIS technology can facilitate the reuse and transformation of data, incorporate forecasting models, and create four-dimensional GIS. It can use knowledge based methods to combine marine and terrestrial environmental data with process simulations. Selected variables can be overlaid on the bathymetry and topography, which are also temporally variable. XML tagging will be supported to allow easy accessibility to various data formats. The combination of XML and ECDIS technology will provide a commonality throughout coastal and oceanic data without proprietary tools, and will facilitate examination and analysis of temporal and spatial relationships between and within the two groups of data.
- The Port of San Diego introduced recently a web-based port management package using ECDIS technology. It provides the harbour authorities with real-time navigational and environmental data inputs and access to the various data bases for presentation through the Internet. The data are presented on top of the Electronic Navigational Chart in form of thematic overlays using ECDIS technology.
- There are no regulatory restrictions on the port or coastal GIS and variables can be dynamically presented. They can include meteorological and oceanographic data and depth adjusted for tides and surges. Practical applications can include presentation of e.g. coastal flooding predictions. ECDIS-type software may become a tool not only for scientists but also for coastal zone managers and insurance offices. Basing such systems on the web will provide the general public with access to important information.
- (*)- SevenCs GmbH, Hamburg, Germany
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- 25
- >Title: Monitoring water level, waves and ice with radar gauges
- >Authors: Dr.-Ing. habil. U. Barjenbruch 1 Dipl.-Phys. Dipl.-Ing. S. Mai 2 Dipl.-Ing. N. Ohle 2 Dipl-Ing. P. Mertinatis 3 -
>Category: Coastal Zone Management- >Keywords
>Abstract of the HYDRO 2002 - 13th BIENNIAL INTERNATIONAL HYDROGRAPHIC SYMPOSIUM- The monitoring at German rivers, estuaries and coasts focuses on the collection of water level data in the moment. Today's standard gauging station is generally based on a float system installed in a well connected to the river respectively to the sea requiring large efforts in installation and maintenance. Parameters like waves and icing are not continuously measured yet. In order to reduce the investment in the gauging system and the cost of maintenance federal authorities think about using new contactless sensors (BARJENBRUCH et al., 2000). Therefore are research program on radar gauges funded by the Federal Ministry of Education and Research (03 KIS 033 / 03 KIS 034) is going on at the German Federal Institute of Hydrology and the Franzius-Institute for Hydraulic, Waterways and Coastal Engineering in the moment. A positive aspect of this measuring principle is its capability to measure water levels, waves and ice thickness with a single sensor at the same time. A first analysis of commercially available radar sensors revealed that the accuracy with respect to the German measurement instructions for water levels is sufficient at inland rivers but not in the coastal zone. With respect to wave monitoring the applicability of these sensors is also restricted (MAI and ZIMMERMANN, 2001).