Hydrography
In Austria there is a different idea of hydrography. It is assigned to the hydrology here. The tasks are not consistent in its entirety with the importance of hydrography in Germany (or the hydrography international), therefore, will be discussed on the Austrian view: By Hydrographic (geographical Hydrology ) refers to the doctrine of forms, properties, occurrence, distribution and budget of the water above, on and below the surface. The hydrography is a part of the geography and geophysics. Their branches are the Hydrology ( limnology ) with its branch river Customer ( Potamologie ), the sources and groundwater customer ( Hydrogeology ), oceanography ( Oceanography ) and the doctrine of bedload movement and Geröllverfrachterung in rivers and coastal areas. The waters of the open seas treated Oceanography ( Oceanography ), the glaciers glaciology ( Glaciology ). This description is broadly in line with that of the hydrology.
- 2.1 Tasks of hydrography in Austria ( the example of the Hydrographic Office in Carinthia )
Definitions
UNESCO and DIN - Definition
The hydrography is " the science and practice of measurement and presentation of the parameters that are necessary to describe the nature and shape of the bottom of the waters, their relationship to the dry land and the condition and dynamics of the waters. " (Definition according to United Nations Economic and Social Council, 1978)
This definition is also held in DIN 18709-3. In DIN designations waters surveying, hydrographic surveying and inland waters are transmitted uniformly with " hydrographic surveying " into English.
The International Hydrographic Organization ( IHO ) defines " Hydrography " as follows:
That branch of applied sciences Which deals with the measurement and description of the features of the seas and coastal areas for the primary purpose of navigation and all other marine purposes and activities - inter alia - offshore activities, research, protection of the environment, and prediction services.
A new definition of " Hydrography " is currently in the IHO discussed ( April, 2009).
Austrian ÖNORM definition
The hydrography is the part of hydrology which, deals with the quantification and description of the water cycle on above and below the earth's surface and with the treatment of related issues. ( Supplementary ÖNORM B 2400 to ÖNORM EN ISO 772 )
This definition is well-known in Austria and Switzerland is unusual in Germany and also fails to take the meaning of the English word " Hydrography ".
Tasks of the Hydrographic
71% of the earth is covered with water. Science has the surface of the planet Mars better mapped than the ground under the water surface. The main responsibilities of the Hydrographic are capturing the nature and shape of the soil under water
- To ensure the safety and efficiency of vessel traffic
- For planning and monitoring measurements for coastal protection
- For monitoring the aquatic environment ( sedimentation, state)
- For (construction) engineering applications ( pipeline, wind turbines, bridge )
- For exploration purposes ( resources from the sea, ...)
- For the ( underwater) archeology ( wreck search, settlement remains under water)
- For research purposes ( Oceanography, Polar Research )
(see also Manual on Hydrography of the International Hydrographic Organization under links).
About 80 % of the transports in the global economy are carried out by sea. The waterways should be monitored regularly in order to avoid accidents. There are still inadequately mapped areas whose Befahrung represents a danger for nature (including human). A driving on areas with non-updated charts is not allowed.
Tasks of hydrography in Austria ( the example of the Hydrographic Office in Carinthia )
The remit of the hydrography in Carinthia includes the area-wide survey of the water cycle by observing and recording of rainfall, air and water temperature, evaporation, basic, rivers and sea water levels and inflows and outflows. These observations and measurements enable the detection of our water resources, show changes in the water balance and are used subsequently to solve a wide variety of water management tasks and problems.
Core tasks of the Hydrographic Office in Carinthia:
- Measuring network construction, maintenance and optimization
- Measurement services and data acquisition ( analog and digital records )
- Data transmission ( telecommunication network), processing and evaluation
- Data Management and Hydrological Data Service
- Hydrographic / hydrologic evaluations, analyzes and studies
- Hydrographic verification of hydraulic engineering and water management projects
- Flood warning service ( disaster )
- Expert services in the official procedures
- Hydrological report
Education and work
Hydrographs are sought, the possibilities are endless. The areas covered range from the programmer in the office to be measured user on the ship. There are good opportunities to work abroad.
Access to the profession manages on studying geomatics or related fields, including geosciences. In German-speaking countries there is a special English-language expression of the 2- year Master's degree program M.Sc. Geomatics at the HafenCity University Hamburg ( HCU) with the highest international certification ( FIG / IHO / ICA Category A). Admission requirements: Bachelor or Diploma in kindred art, proven knowledge of English. Are helpful, good knowledge of mathematics, physics and geography and good technical understanding.
Teaching: Seevermessungstechniker in public administration
Training opportunities, for example through DHyG, DVW, TECHAWI and HCU.
Measurement methods
Hydrographic surveys under water are dominated by acoustic methods ( echo sounders, sonars ) in conjunction with satellite-based positioning the measuring point. Exemplary methods of measurement are the
- Accurate position determination of the ship GNSS (GPS, GLONASS, ...)
- Depth measurements with single beam echo sounders and subjects
- Determination of sediment thickness with sediment echosounders
- Pictorial representation of morphology and objects with sidescan sonars
- Determining flow rates and directions of ultrasonic Doppler flow profile blades ( ADCP )
With modern methods of measurement several thousand points per second can be measured. It can be made with some sensors statements about the nature of the seabed.
More about the methods of measurement may be in the Manual on Hydrography freely available by the International Hydrographic Organization be looked up (see links).