Reference Hydrographics Levels: a Descriptive Approach

Abstract

The execution of a hydrographic survey is a continuous process, from the recognition to the approval of the results in which all the parties involved carry out a detailed. For this, it is important to have specific knowledge of the standards, methodologies and technologies used in hydrography. However, especially in Brazil, the knowledge, the practice and literature about hydrographic surveys still reach smaller proportions than expected from a country with continental dimensions and extensive in coastline. The International Hydrographic Organization specifies that for an hydrographic survey it is necessary to relate all measured depths, regardless of the tide stage or the water level at the time of the survey, to a common hydrographic reference level. Within this context, the objective of this work is to present on the main concepts related to the reference levels considered in studies and hydrographic surveys in coastal and oceanic areas. A bibliographic survey was carried out based on literature, mainly international, of support related to hydrographic surveys, their characterization and methodologies, which served to support the concepts presented here.